Human Reproduction | Practice Question

Here are practice questions for Chapter-3 of Class-XII Biology:- “Human Reproduction”. These questions are based on previous year board question papers, CBSE Sample paper, and NCERT Exemplar and certain other sources.

1 Mark

1. Mention the importance of LH surge during the menstrual cycle.
2. What do you mean by foetal ejection reflex?
3. What is acrosome?
4. Name the embryonic stage that gets implanted in the uterine wall of a human female.
5. Name the fluid which protects an embryo.
6. What is pregnancy hormone?
7. Where are sperm heads found embedded to survive after spermatogenesis?
8. How is oogenesis markedly different from spermatogenesis with respect to growth till puberty in humans?
9. Which cell of the embryo has the potency to give rise to all tissues and organs?
10. Name the sugar present in seminal plasma.
11. Mention the role played by the cell s of alveoli in the mammary glands in human females.
12. How many sperms will be produced by 100 primary spermatocytes?
13. Where is fimbriae found and what role does it play?

2/3 Marks

1. Explain the hormonal control of spermatogenesis in human.
2. What is seminal plasma and what are its components?
3. Explain the steps in the formation of an ovum from an oogonium in humans.
4. Name the hormone produced only during pregnancy in human females. Also, mention their source organ.
5. What are myometrium and endometrium? What role each of them performs in the human female uterus?
6. How is the placenta formed? It acts as an endocrine tissue. Justify.
7. Describe the process of parturition in humans.
8. Explain the role of pituitary and the ovarian hormones in the menstrual cycle in human females.
9. Trace the path of spermatozoa from the testes up to the ejaculatory duct only.
10. Identify ‘a’ to ‘e’ for the following diagram showing the T.S. of the ovary of a human female.
    
11. Why is it important to feed the newborn babies on colostrum?
12. What is the role of mitochondria in the sperm?
13. Why is there no menstruation during pregnancy?
14. What is cervix?
15. What could be the probable reason for the fact that human males in whom the testes fail to descend into the scrotum are generally infertile?

5 Marks

1. What roles do the following structures play in human reproduction
   1. Scrotum
   2. Vas deferens
   3. Epididymis
   4. Inner cell mass
   5. Seminiferous tubules
2. Based on the diagram given below answer the questions that follow. 
   1. Identify the figure that illustrates corpus luteum and name the pituitary hormones that influence its formation.
   2. Specify the endocrine function of corpus luteum. How does it influence the uterus? Why is it essential?
   3. What is the difference between D and E?
   4. Draw a neatly labelled sketch of graffian follicle.
3. Human female is not fertile after menopause whereas males can produce gametes at any age after puberty. Analyze the statement and schematically represent a comparison between gametogenesis in males and females.
4. Explain the process of fertilization and implantation in humans.
5. Based on the graph given below answer the following questions. 
   1. Identify hormone X and Y.
   2. Name the ovarian phases during a menstrual cycle.
      1. 5th day to 12th day of the cycle
      2. 14th day of the cycle
      3. 16th to 25th day of the cycle.
6. The graph given below shows the variation in the levels of ovarian hormones during various phases of the menstrual cycle: 
   1. Identify A and B
   2. Specify the source of the hormone marked in the diagram.
   3. Reason out why A peaks before B.
   4. Under which condition will the levels of B continue to remain high on the 28th day?
7. The following is the illustration of the sequence of ovarian events (a-i) in the human female.

1. 1. Identify the figure that illustrates ovulation and mention the stage of oogenesis it represents.
   2. Name the ovarian hormone and the pituitary hormone that have caused the above-mentioned event.
   3. Explain the changes that occur in the uterus simultaneously in anticipation.
   4. Write the difference between C and H.
   5. Draw a labelled sketch of the structure of a human ovum prior to fertilization.

8. Given below is the diagram of a human ovum surrounded by a few sperms. Observe the diagram and answer the following questions:
   
   1. Compare the fate of sperms shown in the diagram.
   2. What is the role of zona pellucida in this process?
   3. Analyze the changes occurring in the ovum during the process.
   4. How is the entry of sperm into the ovum facilitated?
   5. Specify the region of the female reproductive system where the event represented in the diagram takes place.

Important diagram:

1. Diagrammatic view of male reproductive system
2. Diagrammatic sectional view of seminiferous tubule
3. Diagrammatic sectional view of the female reproductive system
4. Diagrammatic sectional view of a seminiferous tubule
5. Structure of a sperm (very important)
6. Diagrammatic Section view of ovary (very important)
7. Schematic representation of (a) Spermatogenesis; (b) Oogenesis
8. Diagrammatic presentation of various events during a menstrual cycle (very important)
9. Blastocyst (very important)
10. Ovum surrounded by few sperms

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