CBSE Class 12 Biology Human Reproduction MCQs Set 03

Question: The modula continues to divide and form
(a) Blastocyst
(b) Morula
(c) Trophoblast
(d) Blastomere

Answer : A

Question: The outermost layer of embryo is known as
(a) Ectoderm
(b) Epiderm
(c) Mesoderm
(d) Periderm

Answer : A

Question: Which layer of uterine lining exhibits strong contraction during parturition?
(a) Myometrium
(b) Endometrium
(c) Perimetrium
(d) None of these

Answer : A

Question: Both corpus luteum and macula lutea are
(a) found in human ovaries
(b) a source of hormones
(c) characterized by a yellow colour
(d) contributory in maintaining pregnancy

Answer : C

Question: Which one of the following is the most likely root cause why menstruation is not taking place in regularly cycling human female?
(a) Maintenance of the hypertrophical endometrial lining
(b) Maintenance of high concentration of sexhormones in the blood stream
(c) Retention of well-developed corpus luteum
(d) Fertilisation of the ovum

Answer : B

Question: The difference between spermiogenesis and spermiation is
(a) in spermiogenesis spermatids are formed, while in spermiation spermatozoa are formed
(b) in spermiogenesis spermatozoa are formed, while in spermiation spermatids are formed
(c) in spermiogenesis spermatozoa from Sertoli cells are released into the cavity of seminiferous tubules, while in spermiation spermatozoa are formed
(d) in spermiogenesis spermatozoa are formed, while in spermiation spermatozoa are released from Sertoli cells into the cavity of seminiferous tubules.

Answer : D

Question: Extrusion of second polar body from egg occurs
(a) simultaneously with first cleavage
(b) after entry of sperm but before fertilisation
(c) after fertilisation
(d) before entry of sperm into ovum.

Answer : B

Question: Which one of the following statements is false in respect of viability of mammalian sperm?
(a) Sperm is viable for only up to 24 hours.
(b) Survival of sperm depends on the pH of the medium and is more active in alkaline medium.
(c) Viability of sperm is determined by its motility.
(d) Sperms must be concentrated in a thick suspension.

Answer : A

Question: Meroblastic cleavage refers to which type of division of egg
(a) Complete
(b) Spiral
(c) Incomplete
(d) Horizontal

Answer : C

Question: Location and secretion of Leydig’s cells are
(a) liver-cholesterol
(b) ovary-estrogen
(c) testis-testosterone
(d) pancreas-glucagon.

Answer : C

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

Answer : A

Question: After implantation the inner cell mass differentiates into how many layers
(a) Two
(b) One
(c) Three
(d) Four

Answer : C

Question: The zygote further divides by
(a) Mitotic division
(b) Meiotic division
(c) Both (a) and (b)
(d) None of these

Answer : A

Question: Egg is liberated from ovary in
(a) secondary oocyte stage
(b) primary oocyte stage
(c) oogonial stage
(d) mature ovum stage.

Answer : A

Question: What happens during fertilisation in humans after many sperms reach close to the ovum?
(a) Secretions of acrosome helps one sperm enter cytoplasm of ovum through zona pellucida.
(b) All sperms except the one nearest to the ovum lose their tails.
(c) Cells of corona radiata trap all the sperms except one.
(d) Only two sperms nearest the ovum penetrate zona pellucida.

Answer : A

Question: Sertoli cells are found in
(a) ovaries and secrete progesterone
(b) adrenal cortex and secrete adrenaline
(c) seminiferous tubules and provide nutrition to germ cells
(d) pancreas and secrete cholecystokinin.

Answer : C

Question: Signals for parturition originates from
(a) Fully developer foetus
(b) Placenta
(c) Cervix
(d) Both (a) and (b)

Answer : D

Question: The inner cells of biastocyst are called
(a) Inner cell mass
(b) Morula
(c) Trophoblast
(d) None of these

Answer : A

Question: In humans, at the end of the first meiotic division,the male germ cells differentiate into the
(a) spermatids
(b) spermatogonia
(c) primary spermatocytes
(d) secondary spermatocytes.

Answer : D

Question: Which of the following is true regarding sperm?
(a) Fertilizin: For penetrating egg membrane
(b) Hyalurodinase: For penetrating egg membrane
(c) Acrosin: Dissolves corona radiata
(d) Capacitation: Takes place in penis

Answer : B

Question: The Leydig’s cells as found in the human body are the secretory source of
(a) progesterone
(b) intestinal mucus
(c) glucagon
(d) androgens.

Answer : D

Question: Umbilical cord joint
(a) Embryo to cervix
(b) Embryo to uterus
(c) Placenta to uterus
(d) Embryo to placenta

Answer : D

Question: In human female, the blastocyst
(a) forms placenta even before implantation
(b) gets implanted into uterus 3 days after ovulation
(c) gets nutrition from uterine endometrial secretion only after implantation
(d) gets implanted in endometrium by the trophoblast cells.

Answer : D

Question: Sperm and egg nuclei fuse due to
(a) base pairing of their DNA and RNA
(b) formation of hydrogen bonds
(c) mutual attraction due to differences in electrical charges
(d) attraction of their protoplasts.

Answer : D

Question: What is true for cleavage?
(a) Size of embryo increases
(b) Size of cells decreases
(c) Size of cells increases
(d) Size of embryo decreases

Answer : B

Question: Secretions from which one of the following are rich in fructose, calcium and some enzymes?
(a) Male accessory glands
(b) Liver
(c) Pancreas
(d) Salivary glands

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: The part of Fallopian tube closest to the ovary is
(a) isthmus
(b) infundibulum
(c) cervix
(d) ampulla

Answer : B

Question: Ovulation in the human female normally takes place during the menstrual cycle
(a) at the mind secretory phase
(b) just before the end of the secretory phase
(c) at the beginning of the proliferative phase
(d) at the end of the proliferative phase.

Answer : D