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Multiple choice questions (***50 points)

Description: This volume has ***4 pages ***25 questions. 2 points for each question, ***50 points. There is only one best answer to every question. After choosing the correct answer, black out the corresponding letter codes (A, B, C, D) on the answer sheet with 2B pencil. If you need to change it, you must clean it with an eraser before painting other answers.

1. In order to explore the relationship between temperature and cricket chirping, a classmate fed crickets in an environment with temperature as a variable and counted the number of crickets chirping at the same time. The research process mainly adopts

A. Observation B. Experiment C. Measurement D. Investigation

2. During the use of the microscope, crushing and loading often occur. The following table is the investigation and statistical results of the rolling situation and causes of different research groups. Then the reasons for the fragmentation summarized in the table should be:

Structure group

1 group

The two group

trio

quadruplet

Five groups

Low/high power mirror

high

low

high

high

high

Lens barrel state

descend

In the process of repetition, when you fall,

descend

descend

In the process of repetition, when you fall,

Coarse/fine quasi-focus spiral

Rough

Rough

Rough

filmy

filmy

A, use low-power lens and lens barrel down and coarse focusing screw b, use low-power lens and lens barrel up and fine focusing screw.

C, use high-power lens and lens barrel to descend, use coarse quasi-focus spiral D, use high-power lens and lens barrel to ascend, and use fine quasi-focus spiral.

3. Cell division can produce new cells, and cell differentiation can form different cell groups. In this regard, the following description is correct

A. The newly divided cells have the same volume as the mother cells.

B. All cells can divide again after growing to a certain extent.

C. in the process of cell division, the genetic material in the nucleus is copied first.

All cells can divide and differentiate under the control of genetic material.

4. There are many weeds in the poorly managed corn field, which will affect the corn yield, mainly because

A. the result of mutual benefit between weeds and corn B. weeds parasitize corn and affect its growth.

C. weeds affect the quality of corn D. the result of weeds and corn competing for living conditions

If you look closely, you will find that the plants around us have different morphological structures. The following plants are distinguished by roots, stems and leaves.

A. kelp, Spirogyra and bracken

6. The following four groups cultured the same plant under different experimental conditions, and the group with the largest stomatal opening should be this group.

Conditional group

A

B

C

D

soil moisture

damp

damp

damp

dry

Lighting conditions

illuminate

illuminate

dark

illuminate

Temperature level

High-ranking, higher-ranking, more important

reduce

reduce

High-ranking, higher-ranking, more important

There are many kinds and forms of animals in nature. Please say which of the following descriptions is wrong.

Most birds have streamlined bodies and air sacs communicating with the lungs.

B.mammals are born with fur.

C fish belong to vertebrates, and their body temperature will change with the change of temperature.

D. Earthworms are segmented, so earthworms belong to arthropods.

8. All human movements are based on certain structures. The following statement about human body structure is correct.

A. all joints of the human body can move. B. The joint consists of joint head and joint fossa.

C. Joints include articular surface, joint capsule and joint cavity D. Biceps brachii belongs to muscle tissue.

9. In Shouguang's rice fields, farmers have the habit of raising Lentz chickens at home, which makes the traditional chicken breeds continue. The researchers used these chicken breeds to breed a batch of new varieties of Shouguang chicken that meet the modern needs through hybridization.

A. The breeding process of new varieties reflects the genetic diversity.

B the process of cultivating new varieties reflects the diversity of biological species.

C. All the behaviors of chickens are obtained on the basis of genetic factors and through the action of environmental factors.

D. Several domestic hens have nesting phenomenon, which belongs to learning behavior 10. "Superbacteria" is a kind of bacteria that is no longer sensitive to most antibiotics, and its production is related to human abuse of antibiotics. The structural characteristics of "superbacteria" are as follows

A. unformed nucleus B. there is no cell structure like SARS virus

C. it has the same cell structure as fungi. D. it has no DNA

1 1. "The experiment of digesting starch with saliva" needs a certain temperature, because the catalysis of amylase in saliva will gradually decrease under the conditions above and below 37℃. The following figure can correctly show the relationship between the action of salivary amylase and temperature.

12. Vaccinating infants with polio vaccine can prevent polio. The following statement about this vaccine is correct.

A.it is the antigen of human body. B. it can directly kill pathogens that invade the human body.

C.it is an antibody of human body. D. directly participate in the formation of the second line of defense of the human body.

13. When someone is accidentally stabbed by a rusty nail, the doctor will inject tetanus antitoxin serum into the injured person, so that the pathogens that may invade the body will lose their pathogenicity directly. The injected substances and the measures taken are respectively

A. antigen, control the source of infection B. antigen, protect susceptible people

C. antibody, control the source of infection D. antibody, protect the susceptible population

14. Artificial pollination is needed for greenhouse cultivation of silver melon in Qingzhou, but under natural conditions, silver melon belongs to.

A. Self-pollination, mainly by insects B. Cross-pollination, mainly by insects.

C. cross-pollination mainly depends on the wind. Self-pollination mainly depends on the wind.

15. In order to explore the conditions of seed germination, some people selected several mung bean seeds and divided them into four groups on average, and then cultivated them in the same environment in the following ways: ① group: normal temperature+moist soil; ② group: cold storage+moist soil; ③ group: normal temperature+dry soil; ④ Group: normal temperature+moist soil+isolated air. The following statement is correct.

A.① and ② can verify the effect of temperature on seed germination B. ② and ③ can verify the effect of water on seed germination.

C.② and ④ can verify the effect of air on seed germination.

16. Visit Shouguang Food Expo, and you will find that many plants are soilless cultivated with various nutrient solutions, and these plants mainly rely on root tips to absorb nutrients.

A. meridian b area. Elongation zone

C. Mature area D. All areas except root cap

17. The following are the propagation methods used in crop cultivation, among which sexual propagation is

A. shoot propagation of anqiu peach B. seedling propagation and cultivation of chestnut

C, propagating Chinese rose by tissue culture technology; D, cultivating chrysanthemum by a root splitting method.

18. Linqu silkworm belongs to a completely metamorphosed insect, and its development process is the same as that of which of the following organisms.

A. locust B. cricket C. fruit fly D. frog

19. The following statements about human reproduction and development are incorrect.

A. The gonads of male and female are testis and ovary respectively.

B. The uterus is the most important sexual organ for women.

C, the fetus completes the material exchange with the mother through the placenta and umbilical cord.

D. fertilized eggs are the starting point of human individual development.

20. A maize with genome aa and a maize with genome AA pollinate each other, so the maize grains produced by these two maize plants.

A. The genetic composition of embryo is the same, but the genetic composition of seed coat is different. B the genetic components of embryos are different, but the genetic components of seed coat are the same.

C the genetic composition of embryo is the same, and so is the genetic composition of seed coat. D. The genetic composition of embryo is different, so is the genetic composition of seed coat.

2 1. The chemical evolution simulation experiment made by American scientist Miller and others supported the origin of life.

A. inorganic substance → organic small molecule stage B. organic small molecule → organic large molecule stage

C. organic macromolecules → independent system stage D. independent system → primitive life stage

22. Among the organisms included in the following taxonomic units, the highest molecular similarity in protein should be

A.d. door

23. One sperm and three kinds of mature blood cells are from a healthy adult male. The minimum number of Y chromosomes contained in these four cells may be

A.4 Article B.2 Article C. 1 Article D.0

24. A classmate encountered a series of problems in the process of trying to "make yogurt with fresh milk" and "make wine with grapes". The correct analysis is as follows

A. yogurt needs to be sealed, and wine does not need to be sealed.

B. making yogurt and wine needs to be done under oxygen-free conditions.

One microorganism is used to make yogurt, and two microorganisms are used to make wine.

D "bacteria" used to make yogurt and wine can reproduce spores.

25. Low temperature and proper control of oxygen and carbon dioxide concentration can prolong the storage period of fruits and vegetables, mainly because of the environment.

A.it can make breathing strong. It will weaken breathing.

C, the intensity of photosynthesis can be adjusted; D, bacteria and other microorganisms can not survive.