Respiration and Circulation — BIOLOGY STD 12 Science — Question

Distinguish between: Menarche and Menopause.

Read the following and answer any four questions from (i) to (v) given below:
A functional mammary gland is characteristic of all female mammals. Mammary glands are paired structures that contain glandular tissue and variable amount of fat. Refer to the given figure of a mammary gland and answer the following questions.

1. Mammary glands are modified:

1. Sweat glands.
2. Sebaceous glands.
3. Sudoriferous glands.
4. Lacrimal glands.

2. Identify the incorrectly matched pair.

1. P - Areola.
2. Q - Lactiferous duct.
3. S - Mammary duct.
4. T - Mammary alveoli.

3. Mammary ducts expand to form:

1. Mammary alveoli.
2. Mammary ampullae.
3. Lactiferous ducts.
4. Mammary tubules.

4. What is areola?

1. Grape-like clusters of milk secreting structures.
2. Fatty tissue between the mammary lobes.
3. Circular pigmented area of skin around nipple.
4. Connective tissue that supports the alveoli and ducts.

5. Assertion: The size of breast depends on the amount of adipose tissue.

Reason: The adipose tissue supports the alveoli and the ducts.

1. Both assertion and reason are true, and reason is the correct explanation of assertion.
2. Both assertion and reason are true, but reason is not the correct explanation of assertion.
3. Assertion is true, but reason is false.
4. Both assertion and reason are false.

Read the following and answer any four questions from (i) to (v) given below:
The given graphs show fluctuations in blood sugar of person X and Y during a 24 hour time period.

Based on the above information, answer the following questions.

1. Which of the following holds true for person X?

1. Person X is suffering from type I diabetes.
2. Person X shows severe insulin deficiency and beta cell depletion.
3. Person X is normal and shows good control of blood sugar level.
4. Person X is subjected to excessive urination and abnormal thrust.

2. The given graph indicates that person Y is suffering from.

1. Diabetes
2. Hypertension
3. Atherosclerosis
4. Rheumatic heart disease.

3. Which of the following conditions are common in person Y?

1. Excretion of glucose in urine and excessive urination.
2. Polydipsia and mild beta cell depletion.
3. Progressive erosion of articular cartilage at synovial joint.
4. Both (a) and (b).

4. A person suffering from diabetes mellitus becomes weak because.

1. The cells are unable to utilise glucose and other carbohydrates for energy production.
2. Degradation of fat increases production of toxic ketone bodies.
3. Cells utilise proteins for obtaining energy
4. All of these.

5. Assertion: Type I diabetes involves failure of insulin to facilitate the movement of glucose into cells.

Reason: Type II diabetes is caused by failure of beta cells to produce adequate amount of insulin due to beta cell depletion.

1. Both assertion and reason are true, and reason is the correct explanation of assertion.
2. Both assertion and reason are true, but reason is not the correct explanation of assertion.
3. Assertion is true, but reason is false.
4. Both assertion and reason are false.

Distinguish between : Single circulation and Double circulation.

Read the following and answer any four questions from (i) to (v) given below:
Medical termination of pregnancy is termination of pregnancy before the fetus become viable. To reduce the incidence of illegal abortion and consequent maternal mortality, MTP Amendment Act, 2017 was enacted by the government of India. About 40-50 million MTPs are done in a year all over the world.

1. Abortion can be safely done for about ______ weeks of pregnancy.

1. 4
2. 12
3. 8-10
4. 15-18

2. How is MTP helpful in decreasing human population?

1. By aborting normal female fetus.
2. By aborting normal female fetus.
3. By getting rid of unwanted pregnancies.
4. None of these.

3. Select an incorrect statement for MTP.

1. Second trimester abortions are more risky than first trimester.
2. It is being misused to abort normal female fetus.
3. It helps to get rid of unwanted pregnancies.
4. Child detected with congenital heart disease cannot be aborted.

4. MTP was legalised by Government of India in:

1. 1971
2. 1982
3. 1973
4. 1991

5. Assertion: MTPs are safe during first trimester of pregnancy.

Reason: After first trimester, fetus become intimately associated with the maternal tissues.

1. Both assertion and reason are true, and reason is the correct explanation of assertion.
2. Both assertion and reason are true, but reason is not the correct explanation of assertion.
3. Assertion is true, but reason is false.
4. Both assertion and reason are false.

Read the following and answer any four questions from (i) to (v) given below:
Human male reproductive system comprises of a pair of testes, primary sex organs associated with formation of gametes and production of sex hormone. Study the given figure of human male reproductive system and answer the following questions.

1. Which of the following is correct for labelled part P?

1. P is rete testis which transports sperms to outside.
2. P is epididymis which secretes fluid that nourish the sperms.
3. P is epididymis that carry sperms and secretion of seminal vesicles.
4. P is rete testis, which lies along inner side of each testis and stores the sperms.

2. Identify the correctly matched pair.

1. Q - Vasa efferentia.
2. R - Ejaculatory duct.
3. S - Seminal vesicle.
4. T - Cowper's gland.

3. Which statement is incorrect for Q?

1. It carries spermatozoa from epididymis to ejaculatory duct.
2. Q are only 2 in number.
3. It arises from rete testis.
4. It constitutes male sex accessory duct.

4. Which structure passes through the prostate gland and carries sperms and secretion of seminal vesicle?

1. P.
2. T.
3. S.
4. R.

5. Assertion: Mucus present in secretion of bulbourethral gland decreases the number of sperms damaged during ejaculation.

Reason: Mucus lubricates the end of penis and lining of the urethra.

1. Both assertion and reason are true, and reason is the correct explanation of assertion.
2. Both assertion and reason are true, but reason is not the correct explanation of assertion.
3. Assertion is true, but reason is false.
4. Both assertion and reason are false.