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Maturation of whitewashed plants
With the end of the 20 17 college entrance examination mathematics subject, what parents and candidates want to know most is nothing more than the answers to the college entrance examination mathematics questions. Next, I will provide you with the questions and answers of the comprehensive science examination paper of 20 17 National College Entrance Examination for parents and students' reference. I wish the college entrance examination students good results this year.

4. Put the mature white liquor of a certain plant into a solution of substance A with a certain concentration, and find out the volume change trend of its protoplast (that is, the part in the cell wall of the plant cell), as shown in the figure. The following statement is correct.

Substance a did not enter the cell through the cell membrane within 0 ~ 4h hours.

B the cell volume and protoplast volume change equally within 0 ~ 65438±0h.

The osmotic pressure of substance A solution is less than that of cell fluid in 2 ~ 3h.

In the range of 0 ~ 1h, the osmotic pressure of liquid in vacuole is greater than that of cytoplasmic matrix.

The answer to this question is C.

5. The following statement about the regulation of human life activities is wrong.

A. subcutaneous injection of insulin can lower blood sugar.

B. In patients with cerebral cortex damage, knee jerk reflex cannot be completed.

The lack of thyroid hormone in infants will affect the development and function of their nervous system.

D. The pancreas is innervated by reflex arc efferent nerve, and the secretion of pancreatic juice is also regulated by secretin.

The answer to this question is B.

6. If the coat color of mammals is determined by three pairs of independently distributed alleles located on the autosome, then the enzyme encoded by gene A can turn yellow into brown; The enzyme encoded by B gene can convert brown pigment into melanin; The expression product of D gene can completely inhibit the expression of A gene; The expression products of the corresponding recessive alleles A, B and D do not have the above functional departments &: Net. If two homozygous yellow breeds of animals are used as parents, F 1 is yellow, and the number ratio of yellow: brown: black = 52: 3: 9 appears in F2, then the hybrid parent combination is

A.AABBDD×aaBBdd, or AAbbDD×aabbdd.

B.aaBBDD×aabbdd, or aaBBDD×aabbdd

C.aabbDD×aabbdd, or aabbDD×aabbdd

D.AAbbDD×aaBBdd, or AABBDD×aabbdd

The answer to this question is D.

The above are some of the questions and answers in the two-volume science comprehensive examination paper of the national college entrance examination for reference only.