CBSE Class 12 Biology Human Reproduction Assignment Set A

Important Questions for NCERT Class 12 Biology Human Reproduction

Question. Which of the following method of contraception is highly effective but having poor reversibility :
(a) Sterilisation
(b) Oral pills
(c) IUD
(d) Barrier methods
Answer : A

Question. The base of the sertoli cells adhere to the basal lamina and their apical ends frequently expand into the ........... of the seminiferous tubules.
(a) Surface
(b) Lumen
(c) Outer membrane
(d) Inner layer
Answer : B

Question. Which of the following statements is correct :
(a) MTP has a significant role in decreasing the population.
(b) Goverment of India legalised MTP in 1971 with some strict conditions.
(c) MTP is relatively safe during the first trimester.
(d) All the above
Answer : D

Question. In humans which of the following undergoes meiosis II ?
(a) Second polar body
(b) Spermatogonia
(c) Secondary oocyte
(d) Both (1) and (3)
Answer : C

Question. Which of the following statements is correct ?
(a) Hormone releasing I.U.D. make uterus unsuitable for implantation
(b) IUD are ideal contraceptives for the female who want to delay pregnancy
(c) IUD is most widely accepted method of contraception in India.
(d) All the above
Answer : D

Question. In which of the following methods zygotes or early embryo upto 8 blastomeres could be transferred into the fallopian tube ?
(a) GIFT
(b) IUT
(c) ZIFT
(d) ICSI
Answer : C

Question. Intra testicular genital duct system includes :
(a) Tubuli recti, rete testis and ductuli efferentes
(b) Tubuli recti, vas deferens and ejaculatory duct
(c) Urethra, epididymis and Tubuli recti
(d) Seminal vesicle, ejaculatory duct and ampulla
Answer : A

Question. Match the following columns and select the correct option.
Column-I                              Column-II
(A) Placenta                        (i) Androgens
(B) Zona pellucida               (ii) Human Chorionic Gonadotropin (HCG)
(C) Bulbourethral glands      (iii) Layer of the ovum
(D) Leydig cells                   (iv) Lubrication of the penis
(A) (B) (C) (D)
(a) (iv) (iii) (i) (ii)
(b) (i) (iv) (ii) (iii)
(c) (iii) (ii) (iv) (i)
(d) (ii) (iii) (iv) (i) 
Answer: D

Question. Hormones secreted by the placenta to maintain pregnancy are
(a) hCG, hPL, progestogens, prolactin
(b) hCG, hPL, estrogens, relaxin, oxytocin
(c) hCG, hPL, progestogens, estrogens
(d) hCG, progestogens, estrogens, glucocorticoids.
Answer: C

Question. The amnion of mammalian embryo is derived from
(a) ectoderm and mesoderm
(b) endoderm and mesoderm
(c) mesoderm and trophoblast
(d) ectoderm and endoderm. 
Answer: A

Question. Match column I with column II and select the correct option using the given codes.
Column I                           Column II
A. Mons pubis                    (i) Embryo formation
B. Antrum                         (ii) Sperm
C. Trophectoderm              (iii) Female external genitalia
D. Nebenkern                    (iv) Graafian follicle
(a) A-(iii), B-(iv), C-(ii), D-(i)
(b) A-(iii), B-(iv), C-(i), D-(ii)
(c) A-(iii), B-(i), C-(iv), D-(ii)
(d) A-(i), B-(iv), C-(iii), D-(ii) 
Answer: B

Question. Several hormones like hCG, hPL, estrogen, progesterone are produced by
(a) ovary
(b) placenta
(c) fallopian tube
(d) pituitary.
Answer: B

Question. Ectopic pregnancies are referred to as
(a) implantation of defective embryo in the uterus
(b) pregnancies terminated due to hormonal imbalance
(c) pregnancies with genetic abnormality
(d) implantation of embryo at site other than uterus. 
Answer: D

Question. Select the correct option describing gonadotropin activity in a normal pregnant female.
(a) High level of FSH and LH stimulates the thickening of endometrium.
(b) High level of FSH and LH facilitates implantation of the embryo.
(c) High level of hCG stimulates the synthesis of estrogen and progesterone.
(d) High level of hCG stimulates the thickening of endometrium. 
Answer: C

Question. Which one of the following is not the function of placenta?
(a) Facilitates removal of carbon dioxide and waste material from embryo
(b) Secretes oxytocin during parturition
(c) Facilitates supply of oxygen and nutrients to embryo
(d) Secretes estrogen 
Answer: B

Question. The first movements of the fetus and appearance of hair on its head are usually observed during which month of pregnancy?
(a) Fourth month
(b) Fifth month
(c) Sixth month
(d) Third month 
Answer: B

Question. Which extraembryonic membrane in humans prevents desiccation of the embryo inside the uterus?
(a) Yolk sac
(b) Amnion
(c) Chorion
(d) Allantosis 
Answer: B

Question. Which of the following hormones is not a secretion product of human placenta?
(a) Human chorionic gonadotropin
(b) Prolactin
(c) Estrogen
(d) Progesterone 
Answer: B

Question. During embryonic development, the establishment of polarity along anterior/posterior, dorsal/ventral or medial/lateral axis is called
(a) organiser phenomena
(b) axis formation
(c) anamorphosis
(d) pattern formation. 
Answer: A

Question. The extra embryonic membranes of the mammalian embryo are derived from
(a) trophoblast
(b) inner cell mass
(c) formative cells
(d) follicle cells. 
Answer: A

Question. Eye lens is formed from
(a) ectoderm
(b) mesoderm
(c) endoderm
(d) ectoderm and mesoderm.
Answer: A

Question. Gonads develop from embryonic
(a) ectoderm
(b) endoderm
(c) mesoderm
(d) both mesoderm and endoderm. 
Answer: C

Question. Which of these is not an important component of initiation of parturition in humans?
(a) Release of oxytocin
(b) Release of prolactin
(c) Increase in estrogen and progesterone ratio
(d) Synthesis of prostaglandins 
Answer: B

Question. The fetal ejection reflex in humans triggers the release of
(a) oxytocin from fetal pituitary
(b) human chorionic gonadotropin (hCG) from placenta
(c) human placental lactogen (hPL) from placenta
(d) oxytocin from maternal pituitary.
Answer: D

Question. Signals for parturition originate from
(a) both placenta as well as fully developed fetus
(b) oxytocin released from maternal pituitary
(c) placenta only
(d) fully developed fetus only. 
Answer: A

Question. Signals from fully developed fetus and placenta ultimately lead to parturition which requires the release of
(a) estrogen from placenta
(b) oxytocin from maternal pituitary
(c) oxytocin from fetal pituitary
(d) relaxin from placenta. 
Answer: B

Question. Fetal ejection reflex in human female is induced by
(a) release of oxytocin from pituitary
(b) fully developed fetus and placenta
(c) differentiation of mammary glands
(d) pressure exerted by amniotic fluid. 
Answer: B

Question. In human adult females oxytocin
(a) stimulates pituitary to secrete vasopressin
(b) causes strong uterine contractions during parturition
(c) is secreted by anterior pituitary
(d) stimulates growth of mammary glands.
Answer: B 

Question. Parturition is induced by
(a) neural mechanism
(b) endocrine mechanism
(c) neuroendocrine mechanism
(d) hormonal mechanism
Answer : C

Question. Signals for parturition originate from 
(a) Both placenta as well as fully developed foetus
(b) oxytocin released from maternal pituitary
(c) placenta
(d) fully developed foetus
Answer : A 

Question. Identify the correct sequence in which the various stages of parturition take place.
(a) Shedding of placenta→ Dilation of cervix → Delivery of the baby
(b) Dilation of the cervix→ Shedding of placenta → Delivery of the baby
(c) Dilation of the cervix→ Delivery of the baby → Shedding of placenta
(d) None of the above
Answer : C 

Question. Which of the following hormones is responsible for both the milk-ejection reflex and the foetal-ejection reflex? 
(a) Oestrogen
(b) Prolactin
(c) Oxytocin
(d) Relaxin
Answer : C 

Question. Which one of the following is not the function of placenta? 
(a) facilitates supply of oxygen and nutrients to embryo
(b) secretes oestrogen
(c) facilitates removal of carbon dioxide and waste material from embryo
(d) secretes oxytocin during parturition
Answer : D 

Question. Colostrum is important for newly born because
(a) it contains essential antigen
(b) it contains essential antibodies
(c) Both (a) and (b)
(d) it has more nutrients than ordinary milk
Answer : B

Assertion and Reason

In each of the following questions, a statement of Assertion (A) is given and followed by corresponding statement of Reason (R). Of the statements, mark the correct answer as
(a) If both A and R are true and R is the correct explanation of the A
(b) If both A and R are true, but R is not the correct explanation of the A
(c) If A is true, but R is false
(d) If A is false, but R is true 

Question. Assertion (A) In females, parturition is the act of giving birth to a baby. 
Reason (R) Signals for parturition originate from a fully developed foetus.
Answer : B 

Question. Assertion (A) Ovum retains most of the contents of the primary oocyte and is much larger than a spermatozoa.
Reason (R) Ovum needs energy to go about in search of a spermatozoa for fertilisation.
Answer : C 

Question.Assertion (A) The Sertoli cells are present in seminiferous tubules.
Reason (R) Sertoli cells provide nutrition to the germ cells and spermatozoa.
Answer : B 

Question. Assertion (A) The presence of hCG in woman urine is the basis for pregnancy test.
Reason (R) A woman passes out hCG in the urine during pregnancy.
Answer : A 

Question. Assertion (A) The testes are situated outside the abdominal cavity within scrotum.
Reason (R) Muscles in scrotum helps to maintain low temperature of testes, necessary for spermatogenesis.
Answer : A 

Question. Assertion (A) In the testis, spermatogenesis occurs in the seminiferous tubules and testosterone secretion takes place from the Sertoli cells.
Reason (R) Testosterone brings growth and maturation of secondary sex organs and also the development of accessory sex characters.
Answer : D 

Question. Assertion (A) Breastfeeding during initial period of infant growth is recommended.
Reason (R) Colostrum contains several antibodies, essential to render immunity in newborns.
Answer : A 

Question. Assertion (A) Menstrual phase is also compared to shedding tears for the lost ovum.
Reason (R) In the menstrual phase, loss of endometrial lining takes place due to reduced titre of progesterone.
Answer : A 

Statement Based Questions 

Question. Choose the correct statement.
(a) Size of testis is 4-5 cm in length and 1 cm in width
(b) The scrotum is maintained at body temperature
(c) The testes are situated outside the abdominal cavity in humans
(d) The earliest stages of spermatogenesis occur outside the testis
Answer : C 

Question. Choose the incorrect statement (s).
(a) Oogonia are formed and added after birth
(b) Oogenesis is initiated during the embryonic development
(c) No more gamete mother cells are formed in females after birth
(d) All of the above
Answer : A 

Question. Which of the following statement is incorrect?
(a) Each ovary is about 2 to 4 cm in length and is connected to the pelvic wall and uterus by ligaments
(b) Each ovary is covered by a thin epithelium which encloses the ovarian stroma
(c) Ovaries produce several steroid hormones only
(d) the stroma of ovary is divided into a peripheral cortex and an inner medulla
Answer : C 

Question. Select the correct option describing gonadotropin activity in a normal pregnant female.
(a) High level of FSH and LH stimulates the thickening of endometrium
(b) High level of FSH and LH facilitates implantation of the embryo
(c) High level of hCG stimulates the synthesis of oestrogen and progesterone
(d) High level of hCG stimulates the thickening of endometrium
Answer : C 

Question. Consider the following three statements related to the human male reproductive system and select the correct option stating which ones are True (T) and which ones are False (F).
I. Middle piece of spermatozoon is also termed as power house of spermatozoon.
II. Vas deferens joins a duct from seminal vesicle and form vasa efferentia.
III. Semen is a collection of secretions from the seminal vesicles, prostate gland, Cowper’s glands and sperms from testes.
I II III 
(a) T F T
(b) F F T
(c) T T F
(d) F T T
Answer : A 

Question. Read the following statements and select the correct option(s).
I. Maintenance of hygiene and sanitation during menstruation is very important.
II. Primary oocytes surrounded by a layer of granulosa cells and called primary follicle.
III. Seminal plasma is rich in fructose, calcium and certain enzymes.
IV. In females, uterus is single and also called womb.
(a) Only I
(b) I and II
(c) Only III
(d) All of these
Answer : D 

Question. Which of the following statements is correct?
I. Oogenesis is initiated during the embryonic development stage .
II. At puberty only 60, 000-80, 000 primary follicles are left in each ovary.
III. The primary follicles surrounded with manylayers of granulosa cells and form a new theca called secondary follicles.
IV. Changing of sanitary napkins or pads after every 4-5 hours is necessary for maintaining menstrual hygiene.
(a) I and II
(b) I, II, III and IV
(c) I and III
(d) None of these
Answer : B 

Question. Regarding male pronucleus which among the following statement is correct?
I. It is the sperm nucleus after entering the ovum at fertilisation.
II. Both head and neck of sperm contribute to pronucleus formation.
III. Male pronucleus contains mitochondria.
IV. Sperm head contains pronucleus having diploid set of chromosomes.
(a) Only II
(b) III and IV
(c) Only I
(d) II and IV
Answer : C

Matching Type Questions 

Question. Match the following columns.
Column I                             Column II
(Events)                        (Features)
A. Parturition               1. Attachment of zygote to endometrium
B. Gestation                2. Release of egg
C. Ovulation                3. Delivery of baby
D. Implantation           4. Period between fertilisation and the birth
E. Fertilisation             5. Fusion of male and female gametes
Codes
    A B C D E
(a) 2 4 1 5 3
(b) 4 3 1 5 2
(c) 5 1 2 3 4
(d) 3 4 2 1 5
Answer : D 

Question. Match the following columns.
Column I                           Column II
A. Testis                        1. Gives specific constituents to semen
B. Vulva                         2. Oogenesis
C. Prostate fluid              3. Scrotum
D. Production of ova        4. Labia majora
Codes
   A B C D 
(a) 3 4 1 2
(b) 4 2 3 1
(c) 4 3 2 1
(d) 4 3 1 2
Answer : A 

Question. Match the following columns.
Column I                                     Column II
(Female reproductive parts)         (Related to)
A. Ovaries                                    1. Fertilisation
B. Oviduct                                    2. Ovulation
C. Uterus                                     3. Pregnancy
D. Cervix                                     4. Childbirth
Codes
     A B C D 
(a) 2 1 3 4
(b) 1 2 3 4
(c) 4 3 1 2
(d) 2 3 4 1
Answer : A 

Question. Match the following columns.
Column I                        Column II
A. Acrosome                    1. Rudimentary tissue
B. Endometrium               2. Uterus
C. Polar body                   3. Oogenesis
D. Clitoris                        4. Spermatozoa
Codes
      A B C D 
(a) 2 1 4 3
(b) 4 2 3 1
(c) 4 2 1 3
(d) 4 3 1 2
Answer : B

Male and female Reproductive System Questions and Answers

Question. Choose the write anwer

i) Which cells of testes secrete androgens?
a) sertoli cells
b) leydig cells
c) mast cells
d) spermatogonia

ii) Which is the site of fertilization in human being?
a) uterus
b) vagina
c) ampulla –isthmus junction
d) cervix

Answer : i) b) leydig cells  ii) c) ampulla –isthmus junction

Question. The path of sperm transport is given below. Provide the missing steps in blank boxes.

Answer. Vasa efferentia, Vasa differentia. 

Question. Fill the gaps –
i) Seminal plasma constitute ___________,__________ and enzymes.
ii) Lower narrower part of uterus is called____________.
Answer. i) Fructose    ii) Ca. Cervix. 

Question. Match the followings
a) Spermatogonia                                        i) bulbourethral gland
b) Cells that nourish the developing sperm    ii) vasa efferentia
c) Lubrication of penis                                 iii) male germ cells
d) Rete testes opens into                             iv) sertoli cells
Answer. a) iii b) iv c) i   d) ii 

Question. Give correct term for the followings
i) The layer of uterine wall which undergoes cyclic changes during menstrual cycle.S
ii) The cushion-like fatty tissue with pubic hair in female reproductive system.
Answer. i) Endometrium ii) Mons pubis.

Question. Give answer in one word
i)Why testes do lies outside the body?
ii) Where is fimbrae found and what role does it play?
Answer. i) To obtain 2-30 less temperature than normal body temperature which facilitate sperm formation.
ii) It is finger-like structure found in fallopian tube, it is helpful to collect ova.

Gametogenesis and Menstrual cycle Questions and Answers

Question. Give answer for the followings—
i) How can you differentiate between secondary and tertiary follicles formed during oogenesis?
ii) Midd3e piece is a part of sperm, What role does it play?
Answer.
i) Secondary follicle – Surrounded by few granulose cell layers. Without having antrum.
Tertiary follicle - Surrounded by many granulose cell layers divided as theca externa and theca interna, Having with antrum.
ii) Provides energy to tail for movement of sperm.

Question. What does A to F represent in Oogenesis process?

Answer. A- Mitosis B- Primary oocyte C-Meiosis-I D-Sec oocyte E-Meiosis-II F-Ova/ootid 

Question. Fill the gaps –
i) In the mid of menstrual cycle the level of LH reach to its peak that is called____________.
ii) Empty Graafian follicle turned into ___________, and act as an endocrine gland.
Answer. i) LH Surge ii) Corpus luteum.

Question. Write true or false---
i) Oogenesis starts from embryonic period of a female child. True/False
ii) Antrum is the fluidy filled cavity found in sperm. True/False
iii)Polar body contains 23 chromosomes. True/False
iv) Menopause is the onset of puberty. True/False
Answer. i) True ii) false iii) True iv) false.

Question. Give correct term for the followings
i) Give term for conversion of spermatid into sperm.
ii) The membrane by which secondary oocyte surrounded during development of ova.
Answer. i)Spermeiogenesis ii) Zona pellucida.

Fertilization and Implantation Questions and Answers

Question. Give answer for the following—
i) In which state zygote get implanted in human female?
ii) How is cleavage different from mitosis?
Answer. i) Blastocyst/Blastula
ii) In cleavage the size of dividing cells gradually decrease but does not in mitosis.

Question. Choose the right answer-
Blastula is the cavity found in---
a) Morula
b) zygote
c) blastocyst
d) gastrula
Answer. c) blastocyste

Question. Give correct term for the following-
Blastomeres of developing embryo arranged into a outer cell layer and a group of cells in a pole, give term for both.
Answer. Trophoblast and Inner cell mass.

Question. Fill the gap –
In human beings ovulation takes place in the form of ______________.
Answer. Secondary oocyte.

Question. Write true or false---
i) Zygote implanted in fallopian tube of human female.   True/False
ii) Progestogen is necessary for implantation.                 True/False
Answer. i) False   ii) True

Embryonic development and Parturition Questions and Answers

Question. Fill the gaps –
i) The structure which provides vascular connection between fetus and uterus is called _____________
ii) In the later phase of pregnancy a hormone ------------------ is secreted from ovary.
Answer. i)Umblical cord ii)relaxin 

Question. Give term for the statements
i) An intimate connection between mother and foetus.
ii) The cells of inner cell mass capable to develop whole embryo.
Answer. i)Placenta iii)Stem cells 

Question. Give answer for the followings
i) Enlist the hormone secreted only during pregnancy in human female.
ii) Why does initial days milk recommended by doctor? Give term for this.
Answer. i)hCG and hPL
ii)Because it is having with specific antibodies which enhance the immunity of the baby. Colostrum. 

Question. Write true or false---
i) Relaxin triggers the contraction during parturition. True/False
ii) Heart beat of foetus can be listen at the end of first month of gestation period. True/False
Answer. i)False ii)True 

Question. Choose the right answer
i) Which hormone is not secreted by placenta-
a) estrogen b) hPL c) hCG  d) relaxin
Answer. i) d)relaxin 

POINTS TO REMEMBER

Acrosome : A small, sheathy structure at the end of a sperm.

Blastula : A stage of embryogendesis which comes after morula and has a hollow fluid filled space called blastocoel.

Endometrium : Innermost glandular layer lining the uterine cavity.

Foetus : An advanced stage of embryo within the uterus.

Gestation Period : A period between fertilisation of ovum and the birth of a baby.

Hymen : A thin membrane partially covering the vaginal aperture.

Implantation : Fixing of embryo/fertilized egg in uterus. It leads to pregnancy.

Menarche : The beginning of first menstruation in female on attaining puberty.

Menopause : Permanent cessation of menstrual cycle in female. It occurs between the age 45 to 50 years in human female.

Oogenesis : Formation and development of ova in ovary.

Ovulation : Process of release of mature ovum (Secondary oocyte) from the ovary.

Parturition : Process of delivery of the foetus (Child birth).

Puberty : A stage at which immature reproductive system of boy or girl becomes mature.

Scrotum : A muscular pouch which houses two testes.

Spermiation : A process by which spher matozora are released from the sominiferous tubules.

Spermatogenesis : Process of formation of sperm from malegerm. cell in the

Acrosome : A small, sheathy structure at the end of a sperm.

Blastula : A stage of embryogendesis which comes after morula and has a hollow fluid filled space called blastocoel.

Endometrium : Innermost glandular layer lining the uterine cavity.

Foetus : An advanced stage of embryo within the uterus.

Gestation Period : A period between fertilisation of ovum and the birth of a baby

Hymen : A thin membrane partially covering the vaginal aperture.

Implantation : Fixing of embryo/fertilized egg in uterus. It leads to pregnancy.

Menarche : The beginning of first menstruation in female on attaining puberty.

Menopause : Permanent cessation of menstrual cycle in female. It occurs between the age 45 to 50 years in human female.

Oogenesis : Formation and development of ova in ovary.

Ovulation : Process of release of mature ovum (Secondary oocyte) from the ovary.

Parturition : Process of delivery of the foetus (Child birth).

Puberty : A stage at which immature reproductive system of boy or girl becomes mature.

Scrotum : A muscular pouch which houses two testes.

Spermiation : A process by which spher matozora are released from the sominiferous tubules.