Question and answer of junior high school biology competition

20 12 junior high school biology competition rematch test paper

Hour: 100 minute, full mark: 120 minute.

Note to candidates: This volume contains three major types of questions: single-choice questions, multiple-choice questions and short-answer questions, with pages *** 10; Among them, pages 7, 8, 9 and 10 are answer sheets, and candidates only hand in answer sheets.

1. Multiple choice questions: Each question has only one correct answer. Please fill in the answer code on page 7 in the answer column, each

Small problem 1, ***30.

1. Penguins living in low latitudes and hot climates are smaller than those living in high latitudes and cold regions, which is beneficial to heat dissipation. What is a concrete example of this fact?

① Adaptability ② Stress ③ Heredity and variability ④ Competitiveness

A.①② B.③④ C.①③ D.②④

2. The following phenomena are examples in which organisms mainly show adaptability to temperature.

The renal tubules and collecting ducts of terrestrial birds and mammals are very long.

B. Desert rats hibernate, burrow and go out at night.

C. submerged plants such as Ceratophyllum have no cuticle outside epidermal cells, and chloroplasts are large and numerous.

D. Giant algae rooted in the seabed can usually only appear near the mainland coast.

3. The following application examples are wrong, and biotechnology must be adopted.

A. making yogurt-fermentation technology B. cultivating virus-free plants-soilless culture technology

C. The birth of Dolly sheep-cloning technology D. Breeding insect-resistant cotton-transgenic technology

After the Beijing Olympic Games, Italian cyclist Rebellin was found to have taken a new stimulant CERA, so he was disqualified. This new stimulant can continuously promote the oxygen carrying capacity of red blood cells, thus greatly improving the endurance of athletes. After taking CERA, the curve of oxygen carrying capacity of red blood cells in a certain period of time should be

A B C D

In order to explore the conditions of seed germination, some people selected several mung bean seeds, divided them into four groups on average, and then put them in the same environment.

Their cultivation methods are as follows: ① Group: normal temperature+moist soil; ② group: cold storage+moist soil; ③ Normal temperature+group

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.

6. Biological morphological structure always adapts to the growing environment. In a certain area, the temperature is low and humid in spring and high and dry in summer.

There is a plant with different leaf types in spring and summer, and its leaf type data are as follows. The following inference is correct.

Projected surface area (mm2) and skin thickness (? m)

One leaf 292 14

B leaf 144 24

A.a leaves grow in spring, which is beneficial to photosynthesis.

B.b. Leaves grow in spring, which is beneficial to photosynthesis.

C. Leaves grow in summer, which reduces transpiration.

D. Leaves grow in summer to enhance transpiration.

7. The following statements related to fermentation technology are correct.

A. temperature control is one of the key conditions in the fermentation process. Air circulation must be maintained during fermentation.

C, fermentation is completed by yeast; D, adding strains immediately after the tofu is cooked.

8. The picture on the right shows a scientific research group studying the water absorption rate and transpiration rate of a plant.

A graph drawn when the ratio is related. Two curves in the graph represent one day.

Changes of water absorption and transpiration rate in light and dark environment

Please analyze this process according to the diagram. The following statement is wrong.

Point c in the figure indicates that the transpiration rate is equal to the water absorption at time a.

B. during the period from a to b in the figure, the transpiration rate is greater than the water absorption rate.

C. The transpiration rate may be less than the water absorption rate when there is light, and the water absorption rate is always greater than the transpiration rate when it is dark.

D. The transpiration rate may be lower than the water absorption rate in the light, and the water absorption rate is always lower than the transpiration rate in the dark.

9. Xiaoming's apple tree is flourishing, but it falls off after bud formation. According to Xiaoming's biological knowledge,

After timely application of appropriate chemical fertilizer, the phenomenon of falling buds no longer appears, and it soon blooms. please

Ask Xiaoming what chemical fertilizer is?

A. nitrogen fertilizer B. phosphorus fertilizer C. potassium fertilizer D. nitrogen fertilizer and potassium fertilizer

10. At a certain moment, determine the contents of three substances in arterial blood and venous blood of an organ, and their relative values are shown in the following figure.

As shown in the figure, the organ

A. Lung B. Brain C. Muscle D. Small intestine

1 1. According to what you have learned and the analysis of China's national conditions, we should prevent AIDS.

What measures do you think are the main measures to take when it is popular in China?

A. Control the source of infection B. Cut off the route of transmission

C. protect susceptible population D. eliminate four pests and pay attention to hygiene.

12. Someone suffered a lumbar injury, which caused dyskinesia of the right lower limb, but he felt it. The injured part of the patient may be

In the reflex arc

① afferent nerve ② efferent nerve ③ receptor ④ nerve center ⑤ effector

A.②④ B.①④ C.①② D.②⑤

13. The blood types of 18 people were determined by type A and type B serum, and it was found that 7 people had agglutination reaction with type A serum.

Nine people agglutinate with B-type serum, five people agglutinate with both serum, and the rest do not agglutinate.

Set, then type A, type B, type AB and type O are each one.

Specifically, this is a good example.

14. Callus can be formed on human skin. Frostbite and melanin-containing cells produced in winter alternate.

① Epidermis ② Dermal ③ Cuticle ④ Mucous layer.

A.②③④ B.③④① C.④②③ D.③②④

15. The following statement is not directly related to skin color.

An orange-yellow carotene can be converted into vitamin A, which leads to yellow skin.

B. The dermis is rich in capillaries, and the hemoglobin content in the blood is high, so the skin will be ruddy.

C. Often exposed to the sun, melanin in the skin increases, making the skin dark brown.

D. due to the influence of genetic factors, individual skin is albino and morbid.

16. The following organs that do not belong to the pelvic cavity are

A. Kidney B. Bladder

C. rectum

D. uterus

17. The following statement is correct.

A. The two cavities in the human body refer to the thoracic cavity and abdominal cavity. B. Epithelial tissue is the most widely distributed tissue in the human body.

C only 1 holes pass through the diaphragm. The largest cell in the human body is a mature red blood cell.

18. The picture on the right shows the changes of blood sugar and the concentrations of two hormones in the blood after lunch.

Curves a, b and c in the figure represent respectively

A. glucagon, insulin and blood sugar

C. Blood sugar, insulin, glucagon D, glucagon, blood sugar, insulin

19. The following belong to organs.

A. cambium of stem, potato tuber, paramecium mouse

20. "Pregnant in October, giving birth once", thank our mother for giving us life and remember her kindness. Fetus obtained from mother

The way to get nutrition is

A. umbilical cord → placenta → mother → fetus B. placenta → umbilical cord → mother → fetus

C. mother → placenta → umbilical cord → fetus D. mother → umbilical cord → placenta → fetus

2 1. It is known that the DNA content in female breast cells is R, so the DNA content in her egg cells and sciatic nerve cells is R.

The quantities are respectively

A.R/2 R B . R . R . C . R/2 0d . 2r 0

22. On the same grassland, rabbits eat grass and grow rabbit meat, while horses eat grass and grow horse meat. The root cause is

A. The metabolism of rabbits and horses is different. B. The digestion and absorption functions of rabbits and horses are obviously different.

C the cells of rabbits and horses are different in size and shape. The genes on the chromosomes of rabbits and horses are different.

23. What will happen to the oxygen consumption when pigeons and frogs move from 25℃ to 5℃?

A. the oxygen consumption of both animals has decreased. B. The oxygen consumption of frogs increases, while that of pigeons decreases.

C the oxygen consumption of frogs decreases, while that of pigeons increases. The oxygen consumption of both animals has increased.

24. Beijing cultivated high-quality Chinese cabbage varieties, and the largest leaf bulb was only 3.5kg, but after it was introduced to Lhasa. Due to the temperature difference between day and night

Large, long sunshine time, the leaf bulb weighs about 7 kg, but after being introduced back to Beijing, the leaf bulb is only 3.5 kg. from

It can be seen from the introduction process of Chinese cabbage

A. Cabbage is hereditary, but it is not changeable. B. variation caused only by environmental conditions cannot be inherited.

C. Environmental changes can cause heritable variation D. The size of cabbage bulbs is only determined by the environment.

25. The following figure shows the change curve of pest population density after long-term use of a pesticide in farmland. The following statement does not conform to Darwin's progress.

The point is

A. With the use of pesticides, the resistance of pest groups is gradually enhanced.

B. Insecticides mutate pests

The formation of pest resistance is the result of directional selection of pesticides to pests.

D. From the curve changes, it can be known that there are drug-resistant individuals in the pest population.

26. Take aa genome Shuifu peach branches as scions and graft them on Aa genome Shuifu peach rootstock.

The probability that the genome of peach pulp cells becomes Aa is

A.25% B.50% C.75% D. 100%

27. Doctors give patients with hypoglycemia intravenous injection of 5% glucose solution, its main purpose is to

A. supply comprehensive nutrition B. supply energy C. maintain the concentration of cell fluid D. supply water

28. The lowest degree of differentiation among the following human cells is

A. Embryonic stem cells B. Hematopoietic stem cells C. Pancreatic cells D. Muscle cells

29. The extinction of dinosaurs has always been a mystery. Some scientists think that an asteroid hit the earth, which led to the extinction of dinosaurs. The following evidence shows that

What does not support this view is that

A. Mexico discovered a crater 65 million years ago. Dinosaurs became extinct in a relatively short time.

C. dinosaur fossils are often concentrated. D. during the period when the number of dinosaurs decreased, the climate was cold and dry.

30. The following options do not belong to the information exchange between individual animals.

A. white cranes dance to woo. B. The wagging of the bee's tail tells the partner where the honey source is.

C. Squid will release ink when threatened. Insects secrete pheromones to attract the opposite sex.

2. Multiple choice questions: Each of the following questions has two or more correct answers. Please fill in the answer code in the answer column on page 7. If you choose less, choose more or choose the wrong one, you will not score. 2 points for each question ***40 points.

3 1. In the process of seed germination, a series of changes will take place in the morphology and physiology of seeds. The following changes will not occur.

A. The radicle of the seed elongates and breaks through the seed coat. B. The temperature of the seed increases obviously.

C. compared with before germination, the respiration is obviously enhanced. D. the total mass of organic matter in seeds increased obviously.

32. In the narrative of mutual benefit, parasitism, competition and predation, it is incorrect that

A. At least one of these two mutually beneficial creatures can't live independently.

B the parasite belongs to heterotrophs and its host also belongs to heterotrophs.

C. competition is a common form of interspecific struggle. D. predation refers to the relationship between animals.

According to the analysis on the right, the following statement is correct.

A. If Y is used to represent the organic matter content, a → b → c can represent the change of organic matter content from the beginning of seed germination to the growth of green cotyledons of seedlings and then to the growth of seedlings.

B. If Y represents the hemoglobin content in human blood, then a → b → c can represent the change of hemoglobin before and after strenuous exercise.

C. If Y represents the insulin content in the human body, then a → b → c can represent the changes of insulin in the blood of healthy people after eating for a period of time.

D if y represents the amount of carbon dioxide released by seeds in a grain depot, the seed storage effect at point b is better than that at point C.

According to ecological knowledge, Thunderbird feathers can change from white (winter) to taupe (summer) with the change of seasons.

Judging, the following statement is correct.

A. The thinner of the two coat colors is white B. Thunderbird's feathers are constantly crossing, so it can't be used as a protective color.

C. The abiotic factor leading to feather change is mainly sunlight D. Feather change is an adaptation to temperature change.

35. Eupatorium adenophorum, originally from Mexico, was introduced to China, grew wildly in China, occupied the king's land and became the southwest region of China.

Green disaster. The reasons of Eupatorium adenophorum flooding in China are as follows.

A. The climate in southwest China is suitable for the growth of Eupatorium adenophorum. After leaving the country of origin, it lost the control of natural enemies.

C. after leaving the country of origin, it loses the restriction of competing species.

D. after leaving the country of origin, a genetic mutation occurred and became particularly strong.

36. Cucumber flowers are unisexual (that is, a flower has only stamens or pistils), so most of the flowers on cucumber plants will not bear fruit. The reasonable explanation for this phenomenon is

A. flowers that don't bear fruit are because no insects pollinate them.

B. Cucumber is not a green flowering plant and cannot bear fruit.

C. Because the nutrient supply of plants is limited, only a few flowers bear fruit.

D Under normal circumstances, it is the female flower that can bear fruit, and the male flower that cannot bear fruit.

37. Compared with neuromodulation, humoral regulation is characterized by

A, accurate and rapid adjustment; B, through the body fluid transport regulator.

C. Regulators are all produced by endocrine glands. D. the scope of supervision is wide.

38. In the human body directly connected with the pharyngeal cavity are

A. esophagus B. eustachian tube C. oral cavity D. trachea

39. During strenuous exercise, athletes are flushed and sweaty. What function does this reflect on the skin?

A. protect B. regulate body temperature C. excrete and feel external stimuli

40. Normal pancreatic venous blood contains which of the following substances?

A. oxygen B. platelets C. insulin D. insulin

4 1. The following are antigens

A. Type A blood is transfused to type A patients. B. Hepatitis B virus vaccine is given to healthy people.

C. Immune cells produced by autoimmune organs are transplanted to the leg skin on the face of burn patients.

42. In the structure of the eyeball, has the function of refraction is

A. Cornea B. Vitreous body

C. iris

D. lens

Judging from your biological knowledge, the following statement is correct.

A if a student writes a "b" on transparent paper, he should see a "p" in the field of vision of the microscope.

B. Cutting, grafting, leaf propagation and pea seed propagation of pepper grass are all asexual propagation in production practice.

C human life activities are mainly regulated by the nervous system, but also by hormones.

D. The human body has three lines of defense, and the second line of defense is bactericidal substances and phagocytes in body fluids.

44. China scientist Qian Yongjian and others invented the green fluorescent protein labeling technology and won the 2008 Nobel Prize in chemistry. will

The green fluorescent protein gene is implanted into the genetic material of tumor cells. After replication, researchers can track and monitor the swelling.

The growth of tumor cells. Mice with green fluorescent protein gene can see their skin under a special microscope.

The brain and lungs emit green fluorescence. The following statement is true about mice with green fluorescent protein gene.

A. the genes of an organism cannot be changed. B. green fluorescent protein is controlled by green fluorescent protein gene.

C. the green fluorescent protein gene is located on the chromosome. D. the number of genes in the cells of mice is very small.

With the rapid development of science and technology, plant tissue culture technology has been widely used in production practice. This technology

A. It can prevent the harm of plant viruses and improve the efficiency of agricultural production.

B, it can reduce the influence of seasons and speed up reproduction.

Some traits of the female parent can be changed purposefully.

D. The reproductive type of plant tissue culture belongs to asexual reproduction.

46. The following statement is consistent with biological principles.

A. Microbes such as mold, lactic acid bacteria and yeast were used in liquor brewing.

B lactic acid bacteria can produce lactic acid and carbon dioxide during fermentation.

C the principle of dry food storage is to reduce the moisture content in food.

D respiratory depression is the basic principle of storing fresh food.

47.2065438+In February, 2002, an incident of "Live Bears Take Courage" broke out in Guizhentang, Fujian. Do you think this kind of live bear bile extraction?

The effect of fruit juice on black bears is

A. lead to bile deficiency in intestinal and hepatic circulation of black bears. B. lead to endocrine disorders of black bears.

C. lead to gallbladder infection and liver infection in black bears. Causing inflammation and ulcer of bear bile outlet.

48. The way to create new biological species is

A. Transgenic technology B. Cloning technology

C. Plant tissue culture D. Hybrid breeding

49. In July 2009, FINA announced a total ban on "shark skin swimsuits" from 20 10. The core of shark skin swimsuit

This technology is to imitate the skin of sharks. Rough V-shaped wrinkles on the surface of shark skin can reduce the friction of water flow, according to

The developed swimsuit can improve athletes' performance. The following statement is correct.

A. The body temperature of swimmers wearing "shark skin swimsuits" is basically unchanged during the competition.

B. "Shark skin swimsuit" is made by imitating the structure of shark skin.

C. "Shark skin swimsuit" can provide energy for swimmers.

D. The rough V-shaped wrinkles on the shark skin surface are the result of natural selection.

50. The role of animals in nature is

A. Promote the material circulation of the ecosystem B. Absorb oxygen, release carbon dioxide, and make organic matter.

C. Help plants pollinate and spread seeds D. It plays an important role in maintaining ecological balance.

20 12 junior high school biology contest rematch answer sheet

Note to candidates: Only answer sheets will be handed in after the exam.

1, 2, 5 1525, 3545556 General distributor and compound distributor.

I. Graders of multiple-choice questions

QuestionNo.12345678910/2131415438+05 Answer the questionNo.1617655.

Second, multiple-choice questions scored by reviewers

Question 3 1323334353637383940 Answer the question 4142444547484950 Answer the question.

3. Short answer: including 6 small questions, with ***50 points.

5 1.(6 points) phytoplankton (mainly diatoms, etc. ) obvious seasonal changes can be seen in temperate freshwater lakes every year. The following figure shows the relationship between the density of phytoplankton and the changes of environmental conditions such as inorganic nutrients, light and temperature throughout the year.

Please answer according to the diagram analysis:

Please analyze the reasons for two density peaks of phytoplankton.

(2) Why is the peak density in autumn lower than that in spring?

(3) If the lake is slightly polluted by nitrogen and phosphorus in late spring and early summer of a certain year, resulting in the change of inorganic nutrients in the lake (as shown on the right), please draw the change curve of phytoplankton density in that year.

52.(8 points) The human body must absorb all kinds of ready-made nutrients from the external environment to maintain life. Please answer the following questions.

(1) Among the nutrients ingested, those that are not used as energy sources are, etc.

(2) The structural feature of the small intestine suitable for its absorption function is ()

① There are folds in the mucosa of small intestine, and there are many villi on its surface; ② The digestive juice secreted by small intestine glands contains many digestive enzymes.

③ There are microvilli on the free surface of mucosal epithelial cells ④ Digestive juice secreted by pancreas enters the small intestine.

⑤ There are abundant capillaries and lymphatic capillaries in the villi of small intestine.

A.①③⑤ B.①④⑤ C.②④⑤ D.①②③

(3) Three enzymes, A, B and C, were taken from human digestive tract. It is known that the optimum pH values of the three enzymes are 2.0, 9.0 and 7.0 respectively. Under suitable conditions, the three enzyme solutions are mixed with starch, and the results are summarized as shown in Figure A; Mix the three enzyme solutions with egg white respectively, and the results are summarized as shown in Figure B; Three kinds of enzyme solutions were mixed with peptides, and the results were summarized as shown in figure C.

① According to the experimental results, the three enzymes A, B and C are respectively;

② Secreting enzyme A and enzyme C respectively.

53.( 12) In order to study the external factors affecting plant growth, an agricultural research institute planted a variety of plants such as corn and soybeans in the greenhouse. Please answer the following questions:

(1) If the change of CO2 (carbon dioxide) content in the air in a closed greenhouse (constant temperature) is as shown in Figure A, then:

① The point where the intensity of photosynthesis and respiration of plants is equal is the point where the most organic matter is accumulated.

After a day and a night, the organic matter content of plants in the greenhouse will decrease. (Fill in "increase", "decrease" or "unchanged" according to the chart) because.

(2) The curve in Figure B shows the relationship between the photosynthetic intensity of maize and CO2 concentration under a certain light intensity, then:

① If the light intensity decreases, the point A in the curve will move to.

② If other conditions remain unchanged, change the meaning of the ordinate in Figure B to the absorption rate of carbon dioxide. Please draw the corresponding change curve in the coordinate system on the right side of the previous page.

54.(8 points) Silkworms can't eat when they cocoon. Generally, they will produce cocoons with uniform thickness, but sometimes they will produce "thin cocoons" with uneven thickness, which will affect the silk output of silkworm cocoons. In order to find out the reason of "thin cocoon", an exploratory experiment was conducted in May and repeated in September. The experiment is divided into three groups, and the three groups have different light treatments. The experimental results are shown in the following table:

Statistics on the proportion of "thin cocoon"

According to the experiment of grouping processing, the first group, the second group and the third group have bright but uneven light, while the uniform light is dark and uniform. Experiment 1 (May) 15.48% 7.5% 4.92% Experiment 2 (September) 17. 17% 8.85% 4.50% The total average incidence rate was 65438+.

Please answer according to the above situation:

(1) Cocoon is the stage of silkworm moth development, and the development of insects with this stage is called metamorphosis.

(2) The assumption of this group is.

(3) In this experiment, except the age, size and experimental time of silkworm, other experimental conditions should be controlled consistently. Please name one of them.

(4) According to this experiment, how to reduce the incidence of "skinny cocoon"? .

55.(8 points) The experimental process and phenomenon of water temperature change with Daphnia are shown in the figure. Please answer:

The experiment (1) shows that the optimum temperature for most Daphnia is.

(2) Some Daphnia can live in the environment of 200℃ and some Daphnia can live in the environment of 280℃, which shows that there are individual differences among Daphnia individuals, thus reflecting the universal variation of organisms.

(3) In the experiment, Daphnia can survive at 200℃ or 280℃, and they are all adaptive individuals. Therefore, the change of temperature has an effect on Daphnia, and this effect is directional.

(4) Daphnia living at 200℃ will die if it is moved to 280℃; Similarly, Daphnia, which lives at 280℃, will also die if it is moved to 200℃. It shows that when the environmental conditions change, if there is no organism, it will be eliminated by the environment. So the adaptation of organisms to the environment is relative.

56.(8 points) Destroy the frog's brain, preserve the spinal cord, cut the spine at the lower part of the spine, and peel off a pair of spinal nerve roots (including a spinal nerve dorsal root and an abdominal root, as shown in the figure below) on one side of the spinal cord. Electrical stimulation of dorsal root and ventral root can cause motor response of frog's ipsilateral hind limbs. It is known that dorsal root contains afferent nerve, ventral root contains efferent nerve, and dorsal root and ventral root join spinal nerve.

Please design the experimental steps according to the experimental materials provided above (experimental instruments are optional) and predict the experimental results to verify that the dorsal root has the afferent function and the anterior root has the efferent function respectively.

Experimental steps 1:

.

Expected results:

.

Experimental step 2:

.

Expected results:

.

20 12 Reference Answers and Grading Criteria for the Rematch Test Paper of Junior High School Biology Competition

1. Multiple-choice question: 65438+ 0 point for each small question, ***30 points.

Question12345678910131415 Answer the question of CBBBAAADBAAABDA16/kloc-.

Second, multiple-choice questions: if you choose less, choose more or choose wrong, you won't get points, 2 points for each small question, and * * 40 points.

Question 3 1323334353637383940 Answer BDBDBDA, CABCD, DAB, CABD, Question 41424345447484950 Answer ABBDD, CABDB, CABDA, CABDA, CABDA.

3. Short answer questions: including 6 small questions, ***50 points.

5 1. (2 points for each blank, ***6 points) (1) In spring and autumn, the temperature and light are suitable, the inorganic nutrients are sufficient, and phytoplankton produce two density peaks.

(2) Because the accumulation of inorganic nutrients in autumn is less than that in spring.

(3) Draw the curve as shown in the figure below]

52. (2 points per grid, ***8 points) (1) water, inorganic salts and vitamins.

(2) Answer

(3)① pepsin, enteropeptidase and salivary amylase

② Stomach gland and salivary gland

53. (2 points per grid, *** 12 points) (1)①B and DD2 increase the CO2 content at point E lower than that at point A, indicating that the organic matter synthesized by photosynthesis is more than that consumed by respiration.

(2)① Lower left (you can also score if you answer)

(2) As shown on the right (2 points) (the trend of the curve is correct)

54. (2 o'clock in each space, ***8 o'clock) (1) pupae

(2) The brightness and uniformity of light have an influence on the occurrence of "thin cocoon"

(3) Temperature (humidity, same amount of food, etc. (4) Silkworm cocoons are raised in a dark and even environment.

55. (2 points for each space, ***8 points) (1)250C

(2) Non-directional (multi-directional) (3) Selection (4) Adapting to the change of environment.

56.(8 points) Experimental step 1: Cut the central part of the dorsal root (or block it with anesthetic) (1 minute), and electrically stimulate the dorsal root to the middle part and the peripheral part respectively (1 minute, only one of them is given, but not given), and observe whether the frog hind limbs have motor response. Expected results: Frogs whose back roots move to the middle will have motor response; Electrical stimulation of the peripheral segment of the dorsal root did not respond (1), which indicated that the dorsal root had afferent function (1).

The second step of the experiment: cut the ventral root at the center (1 min) (or block it with anesthetic), and electrically stimulate the ventral root to the middle and peripheral segments (1 min, only one of which is not scored) respectively, and observe whether the frog hind limbs have motor response. Expected results: the front root did not respond to the electrical stimulation to the middle part (1), but the hind legs of the frog in the peripheral part of the front root did respond to the electrical stimulation, indicating that the front root had efferent function (1).

Hope to adopt! ! !