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<image>The diagram shows the relationship between the absorption of $$\rm{O_2}$$ and the release of $$\rm{CO_2}$$ in a non-green organ of a certain plant under different $$\rm{O_2}$$ concentration conditions, where the line segment XY = YZ (the respiratory substrate is glucose). Then, when the $$\rm{O_2}$$ concentration is a, the correct statement is ( ).
A. Aerobic respiration consumes more organic matter than anaerobic respiration
B. Aerobic respiration releases the same amount of energy as anaerobic respiration
C. Aerobic respiration releases more energy than anaerobic respiration
D. Aerobic respiration releases more $$\rm{CO_2}$$ than anaerobic respiration
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C
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<image>The diagram shows the fluid mosaic model of the cell membrane. Which of the following statements is incorrect? ( )
A. The side labeled 1 is the exterior side of the cell membrane.
B. 1 is related to the recognition of the cell surface.
C. 2 forms the basic framework of the cell membrane.
D. The selective permeability of the cell membrane is related to the type and quantity of 1.
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D
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<image>In diagram A, a schematic representation of chromosomes and genes of a mammal AaBb at different stages of cell division is shown. Diagram B illustrates the curve of the number of homologous chromosome pairs in the cell at different stages of division. Which of the following statements is correct? ( )
A. In cell 1 of diagram A, crossing over has occurred, located in segment FG of diagram B.
B. In cell 2 of diagram A, there are four sets of chromosomes, located in segment HI of diagram B.
C. In cell 3 of diagram A, there are no homologous chromosomes, but there is segregation of alleles.
D. Cell 4 in diagram A is a daughter cell of 3, and 4 is an egg cell or polar body.
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C
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<image>The diagram below shows images of different stages of mitosis in a cell of a certain organism. Which of the following descriptions of the images is incorrect? ( )
A. Cells A, B, and C are in prophase, anaphase, and metaphase of mitosis, respectively.
B. The ratio of the number of chromosomes to chromatids to DNA molecules in cells A, B, and C is 1:2:1.
C. In cell A, astral rays are emitted from the centrosome, forming the spindle apparatus.
D. This organism cannot be a lower plant cell.
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B
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<image>The diagram shows the energy flow in an ecosystem. Which of the following equations cannot be true? ( )
A. B<sub>2</sub>=A×(10%-20%)
B. A=F+B<sub>1</sub>+C<sub>1</sub>+D<sub>1</sub>+E<sub>1</sub>
C. A-(B<sub>1</sub>+B<sub>3</sub>)=C<sub>1</sub>+C<sub>2</sub>+C<sub>3</sub>
D. C<sub>3</sub>=B<sub>2</sub>×(80%-90%)
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D
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<image>The following four images depict cells in four different states of division from the same organism. Which of the following statements is correct? ( )
A. The normal somatic cells of this organism contain 16 chromosomes
B. The ratio of DNA content between the cells shown in Image 1 and Image 3 is 1:2
C. The processes shown in Image 2 and Image 4 occur only in certain organs
D. From Image 4, it can be concluded that this organism must be a male
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C
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<image>The partial metabolic pathway of phenylalanine in the human body is shown in the diagram below. Based on the diagram, which of the following is correct? ( )
A. Enzyme 1 is not involved in the synthesis of melanin
B. The synthesis of melanin is only related to enzyme 2
C. Genes directly control traits by controlling the structure of proteins
D. Genes indirectly control biological traits by controlling the synthesis of enzymes
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D
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<image>The diagram shows a model of material exchange between a certain tissue cell and the internal environment. Position 5 is the arterial inflow end, and position 1 is the venous outflow end. Which of the following statements is correct? ( )
A. The water in both 1 and 5 comes from 2 and 3.
B. If 3 is an islet B cell, the insulin concentration at position 5 is lower than at position 1 half an hour after a meal.
C. If 3 is a brain cell, the oxygen concentration at position 5 is higher than at position 1, while the blood glucose concentration is the opposite.
D. If 3 is a tissue cell, the material exchange process is 1 → 2 → 3 → 4.
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B
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<image>Protein engineering is a newly emerging field of bioengineering, also known as second-generation genetic engineering. The diagram below illustrates the process of protein engineering, where $$A$$ and $$B$$ in genetics represent ( ).
A. Transcription and translation
B. Translation and transcription
C. Replication and transcription
D. Transfer and expression
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A
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<image>The diagram below is a schematic representation of the regulation of human growth hormone secretion. Which of the following statements is incorrect? ( )
A. If the secretion of growth hormone increases, it may promote the secretion of cell b
B. Cells a and b have a synergistic relationship in regulating the secretion of growth hormone by cell c
C. Acute hypoglycemia causes the pituitary cells to secrete growth hormone, which transmits information throughout the body via the bloodstream
D. Exercise can enhance the body's immune function, one possible reason being that growth hormone can act on the thymus
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B
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<image>The diagram shows the pathways of carbon and hydrogen elements during photosynthesis and cellular respiration in spinach mesophyll cells, where 1 to 6 represent relevant physiological processes. Which of the following statements is incorrect? ( )
A. Processes 1, 2, and 3 do not occur on biological membranes
B. The types of enzymes involved in processes 2, 3, and 5 are different
C. ATP is produced in processes 2, 3, 4, and 5
D. All [H] produced in process 3 comes from pyruvate
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D
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<image>Chlorophyll pigments were extracted from the leaves of the same type of plant grown under normal indoor light and strong outdoor light, and separated using paper chromatography, with results as shown in the diagram. Which of the following statements is correct?
A. The leaves of the indoor plants are more yellowish
B. The leaves of the outdoor plants are more greenish
C. The carotenoid content in the leaves of outdoor plants is greater than the xanthophyll content
D. The chlorophyll a content in the leaves of indoor plants is greater than the chlorophyll b content
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D
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<image>The diagram shows the growth conditions on sides A and B of an oat coleoptile after unilateral light exposure, with the control group not subjected to unilateral light treatment. Which of the following statements is correct? ( )
A. The number of cells on side A is significantly greater than on side B
B. Side B is the light-facing side, and the amount of IAA synthesized is lower than on side A
C. Lateral transport causes uneven distribution of IAA in the region below the tip
D. Before 40 minutes, IAA has no effect on the growth of sides A and B
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C
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<image>The diagram shows the relationship between different stages of cell division and the changes in DNA content per chromosome. Which of the following analyses of the diagram is incorrect? ( )
A. The formation of phosphodiester bonds by DNA polymerase occurs only in segment AB
B. In segment BC, the number of chromosome sets in the cell can be \frac{1} {2} times that of a complete somatic cell
C. In segment CD, the centromere splits into two due to the force of spindle fibers on both sides
D. In segment DE, each chromosome consists of one DNA molecule and histones, etc.
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C
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<image>In pea seeds, yellow color (Y) is dominant over green (y), and round shape (R) is dominant over wrinkled shape (r). When purebred parents with two pairs of contrasting traits are crossed, the F<sub>1</sub> generation is obtained. The F<sub>1</sub> generation is self-crossed, and the distribution of phenotypes in the gametes produced by F<sub>1</sub> and in the F<sub>2</sub> generation is shown in the diagram on the right. The numbers represent four different phenotypes. Based on the diagram, which of the following statements is correct? ( )
A. The law of independent assortment refers to the free combination of female and male gametes during fertilization in the F<sub>1</sub> generation.
B. Observing the pollen of F<sub>1</sub> under a microscope will not yield four types of pollen grains in a 1:1:1:1 ratio.
C. The offspring of Yyrr*yyRr have the four phenotypes shown in the table in a 1:1:1:1 ratio, which can verify the law of independent assortment.
D. Among the four phenotypes in F<sub>2</sub>, the probability of the genotype of recombinant types that can stably inherit traits is \frac{1} {3}
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C
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<image>The diagram shows the relationship between enzyme activity and temperature. Which of the following statements is correct? ( )
A. When the reaction temperature is adjusted from b to the optimal temperature, enzyme activity will definitely increase.
B. When the reaction temperature is adjusted from a to the optimal temperature, enzyme activity increases.
C. Enzyme activity is highest at the optimal temperature, making it the best for enzyme preservation.
D. Enzyme activity at a is lower than at b, indicating that the spatial structure of the enzyme is more severely damaged at a.
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B
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<image>A class of students investigated a single-gene hereditary disease and analyzed a pedigree chart of one family. Which of the following analyses is incorrect? ( )
A. The inheritance pattern of this disease is either autosomal recessive or X-linked recessive.
B. Individuals 1 and 4 definitely carry the pathogenic gene for this disease.
C. The daughter of individuals 6 and 7 may have this hereditary disease.
D. If individual 3 does not carry the pathogenic gene for this hereditary disease, the probability that individuals 3 and 4 will have a normal son is \frac{1} {4}
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D
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<image>The diagram shows the effect of different concentrations of auxin solution on the growth of a certain plant organ. The growth rates are the same at concentrations m and n. Which of the following statements is correct? ( )
A. If i represents the auxin concentration on the lower side of the stem, then the stem can grow away from the ground.
B. If m represents the auxin concentration on the light-facing side of the stem, then the auxin concentration on the shaded side of the stem is greater than n.
C. If n represents the auxin concentration in the apical bud, then the auxin concentration in the first lateral bud is less than i and greater than n.
D. If n represents the auxin concentration on the lower side of a root growing towards the ground, then the auxin concentration on the upper side is greater than m and less than n.
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D
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<image>The diagram shows a pedigree chart of a certain family. The shaded individuals in the chart indicate those from whom the corresponding genetic material cannot be extracted. To determine the parentage relationship between boy 9 and family members 6 and 7, the feasible identification plan is ( )
A. Compare the X chromosome DNA sequence of 9 with that of 2
B. Compare the Y chromosome DNA sequence of 9 with that of 3
C. Compare the Y chromosome DNA sequence of 9 with that of 5
D. Compare the Y chromosome DNA sequence of 9 with that of 8
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C
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<image>The diagram illustrates the effect of environmental factors on the photosynthetic rate of corn. Based on this analysis, the incorrect statement is ( )
A. Before point M in the diagram, the main factor limiting the photosynthetic rate of corn is light intensity.
B. Compared to point b, the content of C<sub>3</sub> in cells is higher at point a.
C. When conditions corresponding to point b persist for a longer time, the content of C<sub>5</sub> in cells is greater than the content of C<sub>3</sub>.
D. The information in the diagram indicates that reasonable dense planting is beneficial for increasing the photosynthetic rate of corn.
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C
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<image>In the diagram, Figure 1 represents the absorption and release curve of $$\ce{CO_{2}}$$ by a cotton plant over a day and night on a sunny day in August; Figure 2 shows four physiological activity states of two organelles in the mesophyll cells of cotton. Which physiological activities shown in Figure 2 occur sequentially at times $$\text{a}$$, $$\text{b}$$, $$\text{c}$$, and $$\text{d}$$ in Figure 1? ( )
A. (1)(2)(3)(4)
B. (3)(2)(4)(1)
C. (3)(4)(1)(2)
D. (4)(3)(2)(1)
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D
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<image>In butterflies, yellow body color $$(\text{C})$$ is dominant over white $$(\text{c})$$, and female individuals are white regardless of their genotype. The clubbed antennae trait is not sex-linked, meaning both males and females can have either clubbed antennae $$(\text{a})$$ or normal type $$(\text{A})$$. Based on the following crossbreeding experiment results, deduce the genotypes of the parents ( )
A. $$\text{Ccaa}$$(father)$$\times \text{CcAa}$$(mother)
B. $$\text{ccAa}$$(father)$$\times \text{CcAa}$$(mother)
C. $$\text{ccAA}$$(mother)$$\times \text{CCaa}$$(mother)
D. $$\text{CcAA}$$(father)$$\times \text{Ccaa}$$(mother)
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C
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<image>The diagram shows a model of a reflex arc. To verify that a certain drug can only block the transmission of excitation between neurons, but cannot block the conduction of excitation along nerve fibers, which of the following experimental operations is not necessary? ( )
A. Without the drug, stimulate at point $$B$$ and observe the phenomenon
B. Place the drug at point $$A$$, stimulate at point $$B$$, and observe the phenomenon
C. Place the drug at point $$B$$, stimulate at point $$C$$, and observe the phenomenon
D. Place the drug at point $$C$$, stimulate at point $$B$$, and observe the phenomenon
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C
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<image>The diagram below represents the process of haploid breeding in rice. The role of treating seedlings with colchicine is ( )
A. Increase mutation frequency
B. Cause the number of chromosomes in cells to double
C. Significantly improve certain traits
D. Obtain seedless fruits
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B
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<image>The diagram below shows the meiosis process of a fruit fly with the genotype E e X^{n} Y, where alleles E and e are located on chromosome 2. Cell c is a gamete with the genotype ee that does not contain sex chromosomes. Which of the following statements is correct? ( )
A. The cell in Diagram I has 8 chromosomes and 4 chromosome sets
B. If cell d can participate in fertilization, then cells a, b, and c are three polar bodies
C. The X and Y chromosomes did not separate normally during process 1.
D. Chromosome 2 did not separate normally during process 3.
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D
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<image>The diagram shows a concept map related to cell division. Which of the following statements is correct? ( )
A. There are no spindle fibers or chromosomes present during the process, and it only occurs in frog red blood cells.
B. In process 2, the number of chromosomes and nuclear DNA molecules exhibit a parallel relationship.
C. The process is beneficial for maintaining the stability of genetic material between parent and daughter cells.
D. The process involves two cell cycles, and spermatogonia proliferate through process 2 or 3.
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C
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<image>Regarding the process shown in the diagram below, which statement is incorrect?
A. A is phosphate, which is the same in different nucleotides.
B. B is a pentose sugar, which is deoxyribose in DNA and ribose in RNA.
C. C is a nitrogenous base, and there are 5 types in the genetic material of the human body.
D. D is a nucleotide, and there are 8 types in a bacterial cell.
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C
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<image>Carbon is one of the essential elements that make up living organisms. The diagram depicts the general process of the carbon cycle. Which of the following statements is incorrect? ( )
A. The food chain in the diagram consists of producers, II, and III
B. In the diagram, I represents the inorganic environment, and the sum of 1, 6, and 8 is the total energy fixed by producers
C. The energy assimilated by organism II is definitely greater than the energy assimilated by organism III
D. In processes 7 and 8, carbon exists in the form of CO<sub>2</sub>, while in processes 2, 3, 4, 5, and 6, it exists as organic matter
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B
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<image>The diagram below is a partial structural schematic of a certain reflex arc, where d is interstitial fluid. If neuron A is stimulated, an action potential can be detected on neuron C and the muscle contracts. Based on the diagram, determine which of the following statements is correct:
A. The structure shown in the diagram contains 2 synapses and 3 synaptic terminals.
B. When an appropriate stimulus is applied at point b, the galvanometer needle deflects only once.
C. Stimulating point c can verify the direction of conduction of excitation in the nerve fiber.
D. Excitation from d→e involves the transformation of 'electrical signal→chemical signal→electrical signal'.
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C
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<image>Plasmids are commonly used as vectors in genetic engineering. The diagram below is a schematic representation of a natural soil Agrobacterium $$\ce{Ti}$$ plasmid structure (indicating some genes and some restriction enzyme sites). According to the diagram, which of the following statements is correct? ( )
A. The terminator in the diagram is a stop codon composed of three adjacent bases
B. The expression vector constructed from this plasmid can be directly introduced into animal cells
C. The plasmid modified with restriction enzyme I and $$\ce{DNA}$$ ligase cannot be cut by restriction enzyme II
D. Treating with restriction enzyme II can prevent the expression vector constructed from this plasmid from causing excessive plant growth
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D
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<image>Figure 1 is an electron micrograph of Drosophila DNA, where the bubble-like structures are called replication bubbles (the parts of DNA currently being replicated); Figure 2 is a schematic diagram of a replication bubble from Figure 1. Which of the following statements is incorrect? ( )
A. DNA replication occurs concurrently with unwinding, with multiple origins and bidirectional replication.
B. DNA replication requires basic conditions such as a template, raw materials, energy, and enzymes.
C. The presence of multiple replication bubbles on a single DNA molecule can increase the efficiency of DNA replication.
D. In Figure 2, enzyme A is helicase, and enzyme B is either DNA polymerase or RNA polymerase.
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D
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<image>The diagram below represents some materials and apparatus used in the experiment for extraction and separation of pigments in green leaves. Which of the following statements is incorrect? ( )
A. In Figure 1, the substances added to the mortar include anhydrous ethanol, $$SiO_{2}$$, and $$CaCO_{3}$$.
B. When pouring the paste-like grinding liquid into 2, a single layer of nylon cloth should be placed at the base of the funnel.
C. The requirements for drawing the fine line of the filtrate in 3 are that it should be thin, even, and straight.
D. In the chromatography results, the pigment band of chlorophyll $$b$$ is the widest, and the fastest diffusing is xanthophyll.
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D
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<image>The diagram shows a pair of homologous chromosomes undergoing pairing during meiosis, with letters representing different genes. The type of variation shown in the diagram is ( )
A. Deletion
B. Duplication
C. Translocation
D. Inversion
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D
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<image>In the diagram, 1 and 2 represent variations occurring on autosomes. The types of variations represented by 1 and 2 are respectively ( )
A. Gene recombination and chromosomal translocation
B. Chromosomal translocation and chromosomal translocation
C. Chromosomal translocation and gene recombination
D. Gene recombination and gene recombination
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A
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<image>The diagram shows a cell division image of a mammal with the genotype AaBBdd during gamete formation. Which of the following statements is correct? ( )
A. The cell contains 6 chromatids, 6 DNA molecules, and 2 sets of chromosomes.
B. The cell can produce two different genotypes of mature gametes.
C. Gene mutation or crossing over occurred during the formation of this cell.
D. This cell cannot be observed in the ovaries of mammals.
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D
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<image>The diagram illustrates the replication of DNA molecules and gene expression in eukaryotic cells. Which of the following statements is correct? ()
A. Process A mainly occurs in the nucleus, while processes B and C mainly occur in the cytoplasm.
B. Both processes A and B require the catalysis of DNA polymerase and helicase.
C. Processes A, B, and C all follow the principle of complementary base pairing.
D. The raw materials required for processes A, B, and C are ribonucleotides, deoxyribonucleotides, and amino acids, respectively.
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C
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<image>The diagram shows a schematic representation of a protein molecule. In the diagram, "▲, ★, ■, ●" represent different types of amino acids. Chain A consists of 21 amino acids, and Chain B consists of 19 amino acids. The "-S-S-" in the diagram is formed during protein processing by removing 2 H from two "-SH" groups. Which of the following statements is incorrect? ( )
A. The formation of this protein may involve the breaking of peptide bonds.
B. This protein molecule contains approximately 20 types of amino acids.
C. The chemical bond represented by "-S-S-" in the diagram is also a peptide bond.
D. The molecular weight decreased by 686 during the formation of this protein molecule.
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C
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<image>The compound that cannot undergo the hydrolysis reaction shown in the diagram is ( )
A. Nucleotide
B. Insulin
C. Salivary amylase
D. Glycogen
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A
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<image>As shown in Figures 1, 2, and 3, these represent substances that make up the cell membrane, and a, b, c represent three different ways substances enter and exit the cell. Which of the following statements is incorrect? ( )
A. The substance 3 on the cell membrane, like substance 2, also has both water-soluble and lipid-soluble parts.
B. Small molecules enter and exit the cell by method b.
C. Certain immunosuppressive drugs can act on 1 to increase the success rate of organ transplants.
D. When substances enter the cell by method c, 3 can change shape.
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B
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<image>The ATP synthase within the cell is mainly composed of two parts: the protein F<sub>0</sub> embedded in the membrane and the protein F<sub>1</sub> protruding outside the membrane. When H<sup>+</sup> passes through ATP synthase along the concentration gradient, it allows ADP and Pi to combine to form ATP, as shown in the figure. Which of the following statements is correct? ( )
A. The way H<sup>+</sup> passes through ATP synthase is active transport
B. ATP synthase provides the necessary activation energy for the formation of ATP
C. The thylakoid membrane of chloroplasts contains both photosynthetic pigments and ATP synthase
D. The process shown can occur in the cytosol and mitochondria of eukaryotic cells
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C
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<image>Currently, by removing 2 alanines from a certain hexapeptide (positions as shown in the figure), several different organic products are obtained, with the removed amino acids existing in a free state. Which of the following statements about this process is correct? ( )
A. The number of peptide bonds decreases by 2
B. The number of hydrogen atoms increases by 4
C. The number of oxygen atoms increases by 2
D. The number of amino and carboxyl groups each increases by 4
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D
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<image>Which of the following statements about the diagram is correct? ( )
A. DD in diagram A, dd in diagram B, and Dd in diagram C are all the same genetic factors
B. The diagrams that correctly represent the essence of the law of segregation are A and B
C. Theoretically, diagram C can produce equal numbers of D and d gametes
D. The law of segregation applies to all organisms
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C
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<image>As shown in the image, a student is using a microscope. Based on the position of the microscope and the person, determine which step the student should complete next in the microscope operation ( )
A. Picking up the microscope
B. Placement
C. Lighting adjustment
D. Focusing and observation
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B
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<image>Research has found that early-onset Alzheimer's disease is closely associated with the apolipoprotein E (ApoE) gene. The ApoE gene is located on chromosome 19 and has three common alleles: ApoE2, ApoE3, and ApoE4. ApoE4 can inhibit the functions of ApoE2 and ApoE3, while also reducing the stability of neuronal cell membranes, leading to neurofibrillary tangles and neuronal death. A research team discovered that both chromosome 19s of a family with early-onset Alzheimer's disease patients carry the ApoE4 gene. The pedigree chart below shows the two genetic diseases affecting this family. Which of the following statements is correct? ( )
A. Both early-onset Alzheimer's disease and hyperuricemia are autosomal recessive genetic diseases.
B. Both III-9 and III-11 must carry the ApoE2 and ApoE3 genes simultaneously.
C. The fact that III-10 has both diseases is due to the pathogenic genes of II-4 being located on chromosome 19.
D. If II-3 and II-4 have another daughter who suffers from both diseases, the probability is \frac{1} {8}
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D
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<image>Below is a diagram illustrating the absorption of water by plant root cells, where water moves from soil solution A$$\longrightarrow $$cell B$$\longrightarrow $$cell C$$\longrightarrow $$cell D. What is the concentration relationship between the cell sap of these three cells and the soil solution? ( ).
A. >B>C>D
B. =B=C=D
C. >C>B>A
D. >C>D>A
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C
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<image>The diagram shows a concept map related to cell division. Which of the following statements is correct? ( )
A. In the process, no spindle fibers or chromosomes appear, and DNA replication does not occur.
B. In the process, the number of chromosomes and nuclear DNA molecules are always equal.
C. The process helps maintain the stability of genetic material between parent and daughter cells.
D. The process involves a cell cycle, and spermatogonia proliferate in the manner of 2. or 3.
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C
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<image>The diagram below shows the composition of a food web in a certain forest ecosystem. Which of the following statements is incorrect? ().
A. There are a total of 3 food chains in the diagram, and the fox occupies two trophic levels simultaneously.
B. When the number of pine caterpillars increases, the number of gray magpies will also increase, thereby suppressing the growth of the pine caterpillar population.
C. There is a negative feedback regulation mechanism within the biological community, which allows the numbers of various organisms to remain relatively stable.
D. The most commonly used method to estimate the population density of gray magpies is the mark-recapture method.
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A
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<image>According to the diagram, which of the following statements is incorrect? ( )
A. The pituitary gland can secrete thyrotropin-releasing hormone, directly regulating the secretion of hormones by the thyroid gland.
B. The pituitary gland can secrete thyroid-stimulating hormone, regulating the secretion of hormones by the thyroid gland.
C. The hypothalamus can regulate the activity of the pituitary gland.
D. An increase in the amount of thyroid hormones inhibits the activity of the hypothalamus and pituitary gland.
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A
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<image>The diagram shows four genetic pedigree charts. Which of the following statements is correct? ( )
A. The inheritance patterns of pedigree A and B are exactly the same
B. In pedigree D, the probability of this couple having another daughter who is normal is $$1/8$$
C. In pedigree B, if the father carries the pathogenic gene, then this genetic disorder is an autosomal recessive disorder
D. In pedigree C, the father cannot carry the pathogenic gene
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C
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<image>CD47 is a transmembrane glycoprotein that can bind to signal regulatory proteins on the surface of macrophages, thereby inhibiting the phagocytic activity of macrophages. The amount of CD47 on the surface of various tumor cells, such as lung cancer and colon cancer, is 6-5 times higher than that of normal cells, leading to a reduced clearance effect of phagocytes on tumor cells. Scientists speculate that monoclonal antibodies against CD47 can relieve the inhibition of macrophages by CD47. To test this, they conducted experiments according to the following procedure. Which of the following statements is correct? ()
A. Repeatedly performing step 1 can isolate monoclonal antibodies from mouse serum.
B. The control group should be set as: a co-culture system of macrophages + normal cells + monoclonal antibodies.
C. This monoclonal antibody can be used to diagnose all cancers, including lung cancer and colon cancer.
D. The phagocytic index of phagocytes in the control group being significantly higher than that in the experimental group can verify the above speculation.
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D
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<image>The diagram represents several physiological processes of a cell. Which of the following statements is incorrect? ( ).
A. 1. represents the process of cell growth
B. Different tissues are formed through 3.
C. 2. represents cell division, resulting in an increase in the number of cells
D. 3. leads to the doubling of the number of chromosomes
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D
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<image>The diagram shows the graph of photosynthesis intensity of a certain plant at 25°C as it changes with light intensity. Which of the following statements is correct? ( )
A. At point a, the physiological activity of mesophyll cells is only affected by temperature.
B. Point c is the light saturation point for this plant.
C. At point b, the amount of O<sub>2</sub> produced by the plant is N<sub>1</sub>.
D. The respiration rate at point d is greater than at point b.
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C
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<image>The diagram shows a schematic representation of the fluid mosaic model of the cell membrane. Which of the following statements is correct? ( )
A. a refers to the tail of the phospholipid molecule, which is hydrophilic
B. c refers to the non-polar head of the phospholipid molecule
C. The protein molecules that make up the cell membrane are stationary
D. The recognition function of the cell membrane is related to e
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D
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<image>As shown in the figure, an experiment was conducted on an isolated nerve fiber, selecting 4 points on the nerve fiber: a, b, c, and d, with bc < cd. Which of the following statements is correct? ( )
A. Stimulating point a, point d becomes excited first, then point b becomes excited
B. Stimulating point a can prove the bidirectionality of nerve conduction
C. Stimulating point c, the galvanometer needle deflects twice in opposite directions
D. Stimulating point c, the potential at point c changes from positive inside and negative outside to negative inside and positive outside
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C
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<image>The curve of the population growth multiplier λ (where λ represents the population size as a multiple of the previous year's population size) of a certain population over 13 years is shown in the figure. Which of the following analyses is correct? ( )
A. The population size remained unchanged for the first 4 years.
B. The population size in the 4th year was larger than in the 5th year.
C. The population size continuously increased from the 11th to the 13th year.
D. The population size in the 9th year was greater than both the 3rd and the 10th year.
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D
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<image>The diagram shows a part of the regulation of water and salt balance in the human body. The incorrect statement is ( )
A. In the diagram, A, B, D, and E are the hypothalamus, pituitary gland, renal tubules and collecting ducts, and cerebral cortex, respectively.
B. C is antidiuretic hormone, which is secreted by A and released by B, promoting the reabsorption of water in the renal tubules and collecting ducts.
C. When the extracellular fluid volume decreases and blood sodium levels drop, the amount of aldosterone secreted by the adrenal medulla decreases.
D. The balance of water and inorganic salts is achieved through the combined effects of neural regulation and hormonal regulation.
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C
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<image>The diagram shows the secretion and action mechanism of female hormones in higher animals. A, B, and C represent organs, while a, b, d, and e represent substances. Processes 1, 2, and 3 are indicated. Based on the diagram, which of the following is incorrect? ( )
A. Female hormones are steroid substances that diffuse freely across the membrane and bind to receptors inside the cell.
B. The cells located at A can both conduct excitation and secrete hormones.
C. The concentration of female hormones in the blood is maintained relatively stable through feedback regulation.
D. This female hormone regulates metabolic processes by influencing the DNA replication process.
|
D
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|
<image>The diagram shows the process by which the flower color of a certain plant is controlled by two pairs of independently inherited genes, A/a and B/b, with one pair located on the X chromosome. A pure white-flowered female plant is crossed with a pure purple-flowered male plant to produce F<sub>1</sub>. Which of the following statements is incorrect? ( )
A. If the ratio of purple flowers to white flowers in F<sub>1</sub> is 1:1, then A/a is located on the X chromosome.
B. If the ratio of purple flowers to blue flowers in F<sub>1</sub> is 1:1, then B/b is located on the X chromosome.
C. If A/a is located on the X chromosome, then the genotype of the parental white flower is bbX<sup>a</sup>X<sup>a</sup>.
D. If the ratio of purple flowers to blue flowers in F<sub>1</sub> is 1:1, and F<sub>1</sub> male and female individuals are crossed to produce F<sub>2</sub>, the probability of blue flowers appearing in F<sub>2</sub> is \frac{3} {8}
|
C
|
|
<image>$$\ce{HIV}$$ can recognize $$\ce{T}$$ cells through $$\ce{CD_{4}}$$ (a receptor protein) on the cell surface (as shown in Figure A). If a large amount of red blood cells modified with $$\ce{CD_{4}}$$ is injected into an $$\ce{AIDS}$$ patient, the red blood cells will also be recognized and invaded by $$\ce{HIV}$$ (as shown in Figure B). Since $$\ce{HIV}$$ cannot replicate inside red blood cells, the red blood cells become 'trap cells' for $$\ce{HIV}$$, providing a new approach for treating $$\ce{AIDS}$$. Based on the material, the following statement is incorrect ( )
A. Both $$\ce{T}$$ cells and red blood cells originate from hematopoietic stem cells in the bone marrow.
B. After invading red blood cells, $$\ce{HIV}$$ will use the materials inside the red blood cells to synthesize new viruses.
C. The massive proliferation of $$\ce{HIV}$$ can reduce the body's specific immune response.
D. $$\ce{CD_{4}}$$ can react with biuret reagent to show a purple color.
|
B
|
|
<image>The color of a certain bird's feathers is controlled by alleles A and a, with more A alleles resulting in more melanin; alleles B and b control the distribution of pigment. Both pairs of genes are located on autosomes. Researchers conducted the hybridization experiment shown in the diagram. Which of the following statements is incorrect? ( )
A. The expression of feather color is not completely dominant
B. The inheritance of these two pairs of genes follows the law of independent assortment
C. The genotype for solid color without pigment dispersion is bb
D. The proportion of homozygotes among the gray-spotted F<sub>2</sub> is 1/3
|
D
|
|
<image>As shown in the figure, a, b, and c are experiments with different treatments on coleoptiles, and d is a plant covered with a paper box, with one side of the box open, exposed to unilateral light. Which of the following descriptions of the experimental results is correct? ( )
A. a and b bend towards the light, c bends away from the light
B. a grows upright, b and c bend towards the light
C. In figure d, if the plant is fixed and the box is rotated, after a period of time, the plant bends to the left
D. In figure d, if the box and the plant are rotated together, the plant bends towards the opening of the box
|
D
|
|
<image>The diagram shows the relationship between the relative quantities of chromosomes and nuclear DNA during the process of mitosis. The cell may be in ( )
A. Prophase or Metaphase
B. Interphase or Telophase
C. Metaphase or Anaphase
D. Anaphase or Telophase
|
A
|
|
<image>In the construction of a new socialist countryside, a certain area in Sichuan has built a new agricultural ecosystem through the construction of biogas digesters and afforestation (as shown in the figure). Which of the following statements is correct? ( )
A. This new agricultural ecosystem is an ecosystem composed of crops, poultry, livestock, humans, and microorganisms.
B. The establishment of this ecosystem has increased the energy utilization rate of each trophic level.
C. Humans are the main component of this ecosystem.
D. This ecosystem focuses on self-regulation within the system and does not require external input.
|
B
|
|
<image>Scientists isolated gene A from a certain organism and dissociated it into two single strands. One of these strands was hybridized with the messenger RNA of gene A, resulting in the pattern shown in the image. An unreasonable explanation for this is ( )
A. Positions 1, 3, 5, and 7 are connected through complementary base pairing
B. Heating to a certain temperature can separate the two strands
C. The diagram contains 8 types of nucleotides, 5 types of bases, and 2 types of base pairs
D. Since fragments 2, 2, and 6 cannot bind with the messenger RNA, fragments 2, 4, and 6 belong to non-gene segments of the DNA molecule
|
D
|
|
<image>In the human body, there is a gluconeogenesis pathway where non-carbohydrate substances are converted into glucose. It has been reported that scientists have discovered a key enzyme involved in gluconeogenesis, PEPCKI, whose process is shown in the diagram. Which of the following statements is incorrect? ( )
A. An excessively high concentration of PEPCKI in cells may lead to the occurrence of diabetes.
B. Inhibiting the acetylation of PEPCKI provides a possibility for the treatment and prevention of diabetes.
C. Glucagon may be related to the expression of PEPCKI activity within cells.
D. The negative feedback regulation shown in the diagram helps maintain homeostasis of the internal environment.
|
B
|
|
<image>The diagram below shows a section of a myelinated nerve fiber. In the axon regions (b, d) wrapped by myelin sheath cells, $$Na^+$$ and $$K^+$$ cannot move in or out of the cell. In the exposed axon regions (a, c, e), $$Na^+$$ and $$K^+$$ can move in and out of the cell without restriction. Which of the following statements is correct? ().
A. The region is in an excited state, and all ions inside the membrane are positive ions.
B. The region is in a resting state, and the cell membrane is more permeable to $$Na^+$$.
C. The potential in region d is negative inside and positive outside, and an action potential cannot be generated.
D. The direction of local current conduction inside the axon is a→c and e→c.
|
C
|
|
<image>The flower color of a certain plant is controlled by a pair of alleles. A plant with yellow flowers is crossed with a plant with white flowers (P), and the results are shown in the diagram. Which of the following statements is correct? ( )
A. Based on process 1, it can be concluded that the parents are both homozygous.
B. Based on process 2, it can be concluded that yellow is a recessive trait.
C. The ratio of yellow-flowered to white-flowered plants in F<sub>2</sub> is 2:3.
D. The genotype of the white-flowered plants in F<sub>1</sub> is the same as that of the white-flowered plants in P.
|
D
|
|
<image>The diagram shows a cell division schematic of an animal with the genotype AABb. Which of the following statements is incorrect? ( )
A. The gene a in this cell is formed due to crossing over during the prophase of the first meiotic division.
B. The gene a in this cell is produced by a mutation from gene A.
C. This cell may form two types of sperm or one type of egg cell.
D. The somatic cells of this animal contain at most four sets of chromosomes.
|
A
|
|
<image>The changes in locust population numbers under different temperature and humidity conditions are shown in the following diagram. Which of the following statements is correct? ( )
A. At a temperature of 32.5 ℃, the range of humidity adaptation for locusts is the narrowest.
B. At a temperature of 35 ℃, a relative humidity of 90% is more favorable for locust survival.
C. Within a certain range, the optimal humidity for locusts increases as the temperature rises.
D. The effects of temperature and humidity on locust population numbers are the same.
|
C
|
|
<image>In an experiment investigating the richness of small animal groups in soil, a biology group designed a device for collecting small animals as shown in the figure. Which of the following statements is correct? ( )
A. The device utilizes the phototaxis of soil animals.
B. The cover's function is to prevent insects from escaping.
C. The metal mesh can prevent small animals from moving downward.
D. A 70% alcohol solution needs to be added to the wide-mouth bottle.
|
D
|
|
<image>The diurnal distribution of two types of planktonic animals, A and B, in a certain sea area is shown in the figure. Which of the following analyses is reasonable? ( )
A. A is phototactic, B is photophobic
B. A and B mainly feed on phytoplankton
C. The distribution of B reflects the vertical structure of the community
D. The rise and fall of A and B reflect the temporal structure of the community
|
D
|
|
<image>A certain interest group conducted an experiment on anaerobic respiration of yeast at room temperature (as shown in the figure). Which of the following is incorrect? ( )
A. The bubbles emerging from the dropper are $$\ce{CO2}$$ produced by the reaction.
B. The main purpose of adding water to the test tube is to create an anaerobic environment.
C. If the water in the test tube is replaced with cold water, the rate of bubble release decreases.
D. A large amount of energy released during anaerobic respiration of yeast is transferred to $$\ce{ATP}$$, and a small portion of the energy in the glucose molecule remains in the alcohol.
|
D
|
|
<image>In an experiment where bacteriophages infect bacteria, the relationship between the incubation time of bacteriophages with bacteria and the intensity of radioactivity might be as follows. The most reasonable association among the following is (bacteriophages labeled with $$^{35}\text{S}$$ are referred to as Group A, and those labeled with $$^{32}\text{P}$$ are referred to as Group B) ( )
A. Group A—supernatant—$$\text{b}$$
B. Group B—precipitate—$$\text{d}$$
C. Group A—precipitate—$$\text{c}$$
D. Group B—supernatant—$$\text{a}$$
|
B
|
|
<image>The diagram below is a schematic of the reflex arc for the knee-jerk reflex. Which of the following statements is correct? ( )
A. In the knee-jerk reflex experiment, a small hammer should be used to tap the area indicated by $$5$$
B. In the knee-jerk reflex, the pathway of impulse conduction is $$5\rightarrow 4 \rightarrow 3\rightarrow 2 \rightarrow 1$$
C. The knee-jerk reflex is a simple reflex, and its neural center is located in the spinal cord
D. The completion of the knee-jerk reflex requires the involvement of certain areas of the cerebral cortex
|
C
|
|
<image>The diagram shows the distribution of three genes a, b, and c on a DNA molecule of a plant cell. In the diagram, I and II are sequences with no genetic effect. Which of the following statements is correct? ( )
A. The deletion of base pairs in a is a chromosomal structural variation.
B. If base pairs in c change, the traits of the organism may not necessarily change.
C. During the tetrad stage of meiosis, crossing over can occur between b and c.
D. Genes are linearly arranged on chromosomes, and there is a start codon at the beginning of a gene.
|
B
|
|
<image>The age structure of a certain population is shown in Figure A, and the growth curve is shown in Figure B. Which of the following statements is correct? ( )
A. The age structure in Figure A is expanding, and it is likely to belong to this age structure during period t<sub>2</sub>
B. The age structure in Figure A is stable, and it is likely to belong to this age structure during period t<sub>2</sub>
C. The age structure in Figure A is expanding, and it is likely to belong to this age structure during period t<sub>1</sub>
D. The age structure in Figure A is stable, and it is likely to belong to this age structure during period t<sub>1</sub>
|
C
|
|
<image>"Locusts darken the sky, leaving no grass behind." The image shows the impact of several types of locusts, each individually, on the yield of pasture in the same grassland during a certain period. Which of the following analyses is incorrect? ( )
A. When population density is the same, the Asian migratory locust causes the most damage to the pasture.
B. If all four types of locusts are present in the grassland simultaneously, their interspecies relationship is competition.
C. When the population density of the narrow-winged locust is less than 5 individuals/m<sup>-2</sup>, the pasture yield increases.
D. The mark-recapture method is commonly used to investigate the population density of the wide-horned locust nymphs (hoppers).
|
D
|
|
<image>The diagram shows a model of a certain cell structure. Which of the following statements about this cell is correct? ( )
A. The cell shown is a plant cell
B. The cell nucleus is not enclosed by a nuclear membrane
C. Contains ribosomes and various other organelles
D. Genetic material is in the form of chromosomes
|
B
|
|
<image>The sex chromosomes of male birds are ZZ, and those of female birds are ZW. In a certain bird species (2N=80), feather color is controlled by three genes located on the Z chromosome (as shown in the figure). D<sup>+</sup> controls gray-red color, D controls blue color, and d controls chocolate color. D<sup>+</sup> is dominant over D and d, and D is dominant over d. Without considering gene mutations, which of the following inferences is reasonable? ( )
A. There are 4 genotypes for gray-red male birds
B. When blue individuals mate, all female offspring in F<sub>1</sub> are blue
C. When gray-red females mate with blue males, the probability of gray-red individuals appearing in F<sub>1</sub> is 1/2
D. Under normal circumstances, this type of bird will form 40 pairs of tetrads during meiosis
|
C
|
|
<image>After the invasion of the yellow-breasted rat into a certain mountainous area, it caused some harm to the ecosystem there. The relationship between the growth rate of its population and time (unit: year) is shown in the figure. Which of the following statements is correct? ()
A. The population size increased continuously during the investigation period.
B. The birth rate of the population first increased and then decreased during the investigation period.
C. The age structure of the population changed from a growing type to a declining type during the investigation period.
D. When the population density is too high, endocrine regulation causes the population's carrying capacity (K value) to decrease.
|
A
|
|
<image>The pUC118 plasmid of Escherichia coli is a commonly used vector in genetic engineering, possessing an ampicillin resistance gene. The unique cleavage site of a certain restriction enzyme in this plasmid is located within the lacZ gene. On a specific selection medium, if the lacZ gene is not disrupted, the E. coli colonies appear blue; if the lacZ gene is disrupted, the colonies appear white. Which statement about the operation shown in the diagram is correct? ().
A. Restriction enzymes should be added to test tube 1
B. Test tube 2 should be treated with $$rm{Ca^{2+}} $$ to introduce the recombinant vector into E. coli lacking the lacZ gene
C. If the E. coli colonies are blue, the plasmid was not introduced into the E. coli
D. In addition to essential nutrients, an appropriate amount of kanamycin should be added to the medium
|
B
|
|
<image>The following curves show two methods of acquiring immunity in the human body. Based on this, which of the following statements is correct? ( )
A. Method 2 is generally used in medicine for immunization prevention.
B. The process of acquiring antibodies using method 2 is called cellular immunity.
C. Using method 1 can provide more lasting immunity than method 2.
D. When a person is bitten by a venomous snake, method 2 should be used immediately for treatment.
|
A
|
|
<image>Some scientists believe that when adult stem cells divide, they always allocate the chromosome with the relatively old DNA strand (immortal strand) to one of the daughter cells, making it an adult stem cell, and allocate the chromosome with the relatively new synthesized strand to the other daughter cell, allowing it to differentiate and gradually age. Which of the following related speculations is incorrect? ( )
A. Aging cells can be detected and eliminated by the immune system.
B. During the division of adult stem cells, DNA replication results in the halving of chromosome numbers.
C. Adult stem cells still retain the ability to divide and differentiate.
D. According to this hypothesis, it can be speculated that the number of adult stem cells in an organism can remain relatively stable.
|
B
|
|
<image>Which of the following correctly reflects the effect of temperature on enzyme activity? ( )
A. C
B. B and C
C. A and D
D. C and D
|
A
|
|
<image>The diagram illustrates the relationships between population characteristics. Based on the diagram, which of the following statements is incorrect? ( )
A. 2, 3, and 4 represent age structure, birth and death rates, immigration and emigration rates, population size, and sex ratio, respectively.
B. The method commonly used to investigate the population density of a certain field mouse is the sampling method.
C. When studying urban population changes, immigration and emigration rates cannot be ignored.
D. Population size is also influenced by natural climate and other factors.
|
B
|
|
<image>The genotype of a certain higher animal is AaBb. The diagram below shows two cells at different stages during the meiosis of an oogonium. Which of the following statements is correct?
A. Cell A is in Anaphase I and contains 2 tetrads
B. Cell B represents a secondary oocyte containing 2 sets of chromosomes
C. Genetic recombination occurred during the formation of cell A from the oogonium
D. The oogonium divides to produce 4 different genotypes of egg cells
|
C
|
|
<image>The diagram shows the energy flow in an ecosystem, where N<sub>1</sub> to N<sub>6</sub> represent energy values. Which of the following statements is correct? ( )
A. The energy assimilated by dung beetles belongs to the second trophic level.
B. The total energy flowing through this ecosystem is N<sub>1</sub>.
C. The ratio for herbivores \frac{N_{5}} {N_{4}} is greater than that for carnivores.
D. The efficiency of energy transfer from the first trophic level to the second trophic level is ( \frac{N_{5}} {N_{2}} )*100%.
|
D
|
|
<image>As shown in the figure, both poles of the galvanometer are connected to the outer surface of the nerve fiber membrane, with a and b representing stimulation points. Which of the following analyses is correct? ( )
A. When unstimulated, the potential measured by the galvanometer is the resting potential
B. When point a is appropriately stimulated, the permeability of the nerve fiber membrane changes
C. When point b is appropriately stimulated, the galvanometer will deflect twice
D. When point a is appropriately stimulated, an action potential can be generated at point b
|
B
|
|
<image>Some proteins in bacteria have disulfide bonds between their peptide chains. It is known that different peptide chains can be separated by electrophoresis due to differences in their relative molecular weights. As shown in Figure A, which is an electrophoresis result of bacterial proteins, '-' represents without reducing agent, with a molecular weight close to 130, and '+' represents with reducing agent forming two molecular weights. It is known that the reducing agent can break disulfide bonds, and 'M' represents proteins with known relative molecular weights. Figure B represents the structural diagram of proteins or polypeptides. Based on the results in Figure A, which diagram in Figure B best represents the original protein structure of the bacteria (in Figure B, '-' represents the position of disulfide bonds) ( )
A. A
B. B
C. C
D. D
|
B
|
|
<image>In the diagram, X, Y, and Z represent three endocrine glands in the human body, and A, B, and C represent the hormones they secrete. The arrows indicate the relationships between them. Which of the following statements is correct? ( )
A. If Y is removed, the weight of Z will not change.
B. X and Y are connected only through humoral regulation.
C. A promotes Y, B promotes Z, and C promotes both X and Y.
D. If Z represents the thyroid gland, then a deficiency of B and C during childhood will lead to short stature.
|
D
|
|
<image>In a certain type of animal, black and white fur colors are a pair of contrasting traits, controlled by a pair of alleles located on an autosome. Black is dominant (W), and white is recessive (w). The diagram shows two mating events, where the parent animals A, B, P, and Q are all homozygous. The offspring animals grow in different environments, and their fur colors are shown in the diagram. Which of the following analyses is incorrect? ( )
A. Animals C and D have different phenotypes but the same genotype.
B. When animal C mates with animal R, if the offspring grow at -15°C, the most likely phenotype ratio is 1:1.
C. When animal C mates with animal R, if the offspring grow at 30°C, the most likely phenotype ratio is 1:1.
D. Phenotype is the result of the interaction between genes and the environment.
|
C
|
|
<image>In the diagrams, both Figure A and Figure B represent the changes in the release of $$\ce{CO_{2}}$$ and the absorption of $$\ce{O}_{2}$$ by a non-green organ of a certain plant. Which of the following statements is incorrect? ( )
A. The situation in Figure A when the $$\ce{O}_{2}$$ concentration is $$a$$ corresponds to point $$A$$ in Figure B.
B. The situation in Figure A when the $$\ce{O}_{2}$$ concentration is $$b$$ corresponds to segment $$CD$$ in Figure B.
C. Among $$a$$, $$b$$, $$c$$, and $$d$$ in Figure A, the $$\ce{O}_{2}$$ concentration at $$c$$ is most suitable for storing plant organs.
D. When the $$\ce{O}_{2}$$ concentration is $$d$$ in Figure A, no alcohol is produced.
|
B
|
|
<image>Figure A represents a series of changes in a chromosome (or chromatin) during the cell division process of a certain diploid organism. Figure B represents the related curves of the quantity of substances or structures during the cell division of this organism. Which of the following statements is correct? ( )
A. Gene recombination cannot occur at point a
B. Figure A can represent the complete morphological changes of a chromosome during one cell division
C. If the curve in Figure B represents part of the change in the number of chromosome sets during meiosis, then n=2
D. The ab segment in Figure B can represent process 3 in Figure A
|
D
|
|
<image>Regarding the statements related to the four different organisms shown in the figure, which one is incorrect? ( )
A. Both organism A and B have a cell wall and a nucleoid
B. Organism C does not belong to the levels of organization in a biological system
C. The absorption of nutrients by organism D's cells reflects the function of the cell membrane
D. The main difference between organism B and D is that D lacks a nuclear membrane
|
C
|
|
<image>Changshun green-shell egg chicken (sex determination method ZW type) is a valuable resource in the mountainous areas of Guizhou. To explore the genetic inheritance pattern of shank color in green-shell egg chickens and the feasibility of using shank color to distinguish between sexes, breeders conducted the crossbreeding experiment shown in the figure. The incorrect analysis is ( )
A. According to the results of the first cross, it can be determined that the gene is located on an autosome
B. According to the results of the first cross, it is impossible to determine the dominance or recessiveness of the gene
C. According to the results of the second cross, it can be determined that light-colored shanks are a dominant trait
D. The results of the second cross indicate that shank color can be used to distinguish between sexes
|
A
|
|
<image>Which of the following is not part of the 'protoplast' structure during plasmolysis in plant cells? ( )
A. Cell membrane
B. Tonoplast
C. Cytoplasm
D. Cell wall
|
D
|
|
<image>The diagram shows the relationship between enzyme activity and temperature. Which of the following statements is incorrect? ( )
A. t<sub>2</sub> is the optimal temperature for the enzyme.
B. When the reaction temperature is increased from t<sub>1</sub> to t<sub>2</sub>, enzyme activity will increase.
C. When the reaction temperature is increased from t<sub>2</sub> to t<sub>3</sub>, the rate of the enzyme-catalyzed reaction will decrease.
D. The spatial structure of the enzyme before t<sub>3</sub> is the same as that at t<sub>1</sub>.
|
D
|
|
<image>Whether rabbits produce yellow fat or white fat in their bodies is determined by genetic factors. A breeding facility selected healthy yellow-fat rabbits and white-fat rabbits for research. Both types of rabbits were divided into two groups and fed different diets: one group was fed a diet containing yellow pigment, while the other group was fed a diet without yellow pigment. The resulting fat color in the rabbits' bodies was as follows: Which of the following statements is correct? ( )
A. The fat color of rabbits is not determined by genes.
B. The yellow fat genetic factor mutates due to food.
C. The white fat genetic factor mutates due to food.
D. The white fat genetic factor ensures that the fat color of rabbits is not affected by food.
|
D
|
|
<image>The diagram illustrates the actions of elbow flexion and elbow extension in humans. Which of the following statements is correct? ( )
A. During elbow flexion, 1. the biceps brachii relaxes, and 2. the triceps brachii contracts.
B. 3. represents the muscle belly of skeletal muscle, and 4. represents the tendon of skeletal muscle.
C. 1. and 2. work together to move the bones, completing the actions of elbow flexion or extension.
D. Performing elbow flexion upon hearing a command is achieved through the central nervous system.
|
C
|
|
<image>Which of the following statements about the diagram below is correct? ( )
A. The essence of the law of independent assortment is reflected in processes 4, 5, and 6 in the diagram.
B. Process 6 represents the process of meiosis.
C. The randomness of process 3 in Diagram A is one of the reasons why the proportion of Aa in the offspring is 1/2.
D. In Diagram B, the proportion of aaBB individuals among aaB_ individuals in the offspring is 1/16.
|
C
|
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