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Q1. Which of the following is correct about mammalian testes?

• Graafian follicles, Sertoli cells, Leydig cells
• Sertoli cells, Seminiferous tubules, Leydig cells
• Graafian follicles, Leydig cells, Seminiferous tubules
• Graafian follicle, Sertoli cells, Seminiferous tubules

Solution

Graafian follicle is a structure formed in the female reproductive system. Sertoli cells, seminiferous tubules and leydig cells are associated with the male reproductive system.

Q2. Which of the following occurs during spermatocytogenesis?

• Loss of water
• Loss of Golgi apparatus
• Movement of cell organelles to their respective position
• Replication of DNA

Solution

During spermatocytogenesis, the DNA of the cell replicates and the cytoplasm is added to the developing sperm.

Q3. At the end of pregnancy, the hormone relaxin is secreted by

• Corpus luteum
• Corpus albicans
• Vagina
• Uterus

Solution

The corpus luteum secretes two hormones—progesterone during pregnancy and relaxin at the end of pregnancy.

Q4. Which among the following has 23 chromosomes?

• Spermatogonia
• Zygote
• Secondary oocyte
• Oogonia

Solution

Spermatogonia, zygote and oogonia have 46 chromosomes each.

Q5. Vasocongestion in the penis leads to

• Erection
• Subsidence of erection
• Rupture of arterial walls in the penis
• Release of sperms

Solution

The filling up of the sinuses of the penis with blood from the arteries is known as vasocongestion. This builds up the hydraulic pressure in the penis leading to the erection of the penis.

Q6. Human placenta is derived from:

• Chorion
• Allantois
• Amnion
• Allantois and chorion

Solution

The human placenta consists of chorion only. Hence, it is also called chorionic placenta.

Q7. A human female reaches menopause around the age of:

• 70 years
• 25 years
• 15 years
• 50 years

Solution

Woman stops producing mature eggs and ceases her menstrual cycle in her late 40s or early 50s.

Q8. The receptors found on the zona pellucida of the ova which recognise and bind to the sperm are

• ZP1
• ZP2
• ZP3
• ZP4

Solution

ZP3 receptors are glycoproteins found on the zona pellucida which recognise and bind the sperms and induce the acrosome to release hydrolytic enzymes.

Q9. Corpus luteum in mammals occurs in:

• Skin and acts as pain receptor
• Heart and initiates atrial contraction
• Ovaries and produce progesterone
• Brain and connects lobes of cerebrum

Solution

The follicular cells of the empty Graafian follicle form a yellow body called corpus luteum. The corpus luteum secretes progesterone and a smaller amount of estradiol.

Q10. Onset of menstruation is due to:

• Increase in level of progesterone
• Fall in level of progesterone
• Increase in level of FSH
• None of these

Solution

Falling levels of progesterone trigger menstruation and the beginning of the next menstrual cycle.

Q11. Which of the germ layers is best associated with development of heart?

• Ectoderm
• Endoderm
• Mesoderm
• All of these

Solution

Ectoderm forms the lining of gut, gastric and intestinal glands, tongue epithelium, liver, pancreas etc. Endoderm gives rise to epidermis of skin, nasal epithelium, lacrimal glands, salivary glands, enamel of teeth etc.

Q12. Spermatogenesis is promoted by:

• Estrogens
• Progesterone
• Testosterone
• Oxytocin

Solution

Spermatogenesis is promoted by the male sex hormone testosterone.

Q13. Uterine contractions during parturition are stimulated by

• Oxytocin
• Progesterone
• Relaxin
• Oestrogen

Solution

During parturition, the posterior pituitary releases oxytocin which stimulates the contraction of the uterine walls.

Q14. An example of centrolecithal egg is:

• Frog
• Fish
• Cat
• Insect

Solution

Centrolecithal egg is an egg in which the yolk is concentrated near the centre of the egg cell, as is the case in many of the insects.

Q15. The complete development of a sperm in the male reproductive system takes how much time?

• 10 days
• 1 month
• 2 months
• 5 months

Solution

The complete development of a sperm in the male reproductive system takes about 2 months.

Q16. The development of the ova completes after

• Primary oocyte stage
• Secondary oocyte stage
• Fertilisation
• Meiosis-I

Solution

An ovum is released after the secondary oocyte stage and its maturation is completed after fertilisation.

Q17. Crossing over in gamete formation occurs during

• Mitosis
• Cytokinesis
• Meiosis-I
• Meiosis-II

Solution

Meiosis-I is associated with crossing over of homologous chromatids, which introduces variations in the chromosomes and the gametes thus formed.

Q18. Which one of the following is not a male accessory gland?

• Seminal vesicle
• Ampulla
• Prostate
• Bulbourethral gland

Solution

Ampulla is the long, wide, thin-walled major part of the fallopian tube next to the infundibulum.

Q19. The plasma membrane of the ovum is known as

• Oolemma
• Ooplasm
• Alecithal
• Zona pellucida

Solution

The plasma membrane of the ovum is known as the oolemma. The cytoplasm is known as the ooplasm. Alecithal is the condition of lacking a yolk sac in the ovum. Zona pellucida is the inner, transparent, non-cellular egg coat of the ovum.

Q20. Which one of the following arises from endoderm?

• Eye
• Pigment cells
• Heart
• Lungs

Solution

Eye, pigment cells and heart arise from the mesoderm.

Q21. Cessation of menstrual cycle in female is called:

• Menopause
• Ovulation
• Lactation
• Parturition

Solution

A woman stops producing mature eggs and ceases her menstrual cycle in her late 40s or early 50s. This phase is called menopause.

Q22. How long do spermatozoa survive in the female reproductive tract? 

• 1-2 hours
• 1 day
• 1-3 days
• 5 days

Solution

Spermatozoa once released into the female reproductive tract can survive for about 1-3 days.

Q23. Which of the following statements is correct?

• Corpus luteum changes into corpus albicans
• Corpus luteum persists throughout pregnancy
• Corpus luteum degenerates after fertilization
• Corpus luteum is not formed during pregnancy

Solution

If the oocyte is not fertilized, the corpus luteum degenerates in 10-12 days after ovulation and forms the corpus luteum of menstruation and is eventually transformed into a white scar, the corpus albicans.

Q24. Spermiation is the process of the release of sperms from:

• Seminiferous tubules
• Vas deferens
• Epididymis
• Prostate gland

Solution

The process of release of spermatozoa or sperms from Sertoli cells into the cavity of seminiferous tubules is called spermiation.

Q25. The middle portion of the epididymis is known as

• Caput epididymis
• Cauda epididymis
• Corpus epididymis
• Caustic epididymis

Solution

The epididymis is divided into three regions—the upper, wider portion known as the caput epididymis, the middle narrow corpus epididymis and the lower cauda epididymis.

Q26. ICSH is secreted by

• Anterior pituitary
• Posterior pituitary
• Hypothalamus
• Thyroid

Solution

ICSH is secreted by the anterior pituitary.

Q27. The septa of the testis is formed by the inward growth of

• Tunica albuginea
• Tunica vaginalis
• Tunica vasculosa
• Spermatic cords

Solution

The tunica albuginea shows inward growth in the testis, called septa, which divides each testis into 200 to 300 lobules.

Q28. A fluid-filled cavity present within blastula is called:

• Archenteron
• Blastocoel
• Blastoderm
• Blastopore

Solution

The fluid absorbed by the trophoblast layer of the blastula collects in a cavity, the blastocoel or blastocyst cavity that separates the trophoblast from the inner cell mass.

Q29. Acrosome is made up of:

• Golgi bodies
• Mitochondria
• Ribosomes
• Centrioles

Solution

Acrosome is formed from Golgi complex. It contains hydrolytic enzymes and is used to contact and penetrate the egg in fertilisation.

Q30. The ploidy level of each polar body formed in oogenesis is

• Haploid
• Diploid
• Triploid
• Without chromosomes

Solution

The polar body is formed during meiosis-II and hence is haploid.

Q31. In which part of sperm, mitochondria are present?

• Head
• Tail
• Neck
• Middle piece

Solution

The middle piece contains many mitochondria tightly coiled round the axial filament. The mitochondria provide energy for the movement for sperm in the female genital tract.

Q32. In the ovum, meiosis-II is completed after

• Entry of the sperm
• Binding of the sperm to ZP3
• Copulation
• Release of progesterone by the corpus luteum

Solution

The entry of the sperm in the ovum stimulates the egg to resume and complete its suspended meiosis-II division, thus forming a mature egg cell.

Q33. Which of the following components is found in a higher concentration in human milk as compared to cow’s milk?

• Casein
• Calcium
• Lactose
• Phosphorus

Solution

Human milk contains a higher concentration of lactose (7 g/100 ml) as compared to cow’s milk (4.8 g/100 ml).

Q34. The inability of a male to achieve or hold onto an erection for complete copulation is known as

• Sterility
• Impotence
• Prostatomegaly
• Prostatic hypertrophy

Solution

The inability of a male to achieve or hold onto an erection for complete copulation is known as impotence. Sterility is the inability of the male sperm to fertilise the ovum. Prostatic hypertrophy or prostatomegaly is the enlargement of the prostate gland.

Q35. Choose the incorrect statement from the following:

• In birds and mammals internal fertilisation takes place.
• Colostrum contains antibodies and nutrients.
• Polyspermy is prevented by the chemical changes in the egg surface.
• In the human female implantation occurs almost seven days after fertilisation.

Solution

Binding of the sperm to the egg induces depolarisation of the egg plasma membrane which causes fast block to polyspermy.

Q36. Seminal plasma, the fluid part of semen is contributed by: (i) Seminal vesicle (ii) Prostate (iii) Urethra (iv) Bulbourethral gland

• (i) and (ii)
• (i), (ii) and (iv)
• (ii), (iii) and (iv)
• (i) and (iv)

Solution

Seminal plasma, the fluid part of semen is contributed by seminal vesicle, prostate and bulbourethral gland, which are the parts of male reproductive system. Urethra is a part of the female reproductive system.

Q37. Identify the incorrect statement from the following:

• High levels of estrogen trigger the ovulatory surge.
• Oogonial cells start to proliferate and give rise to functional ova in regular cycles from puberty onwards.
• Sperms released from seminiferous tubules are poorly motile/non-motile.
• Progesterone level is high during the post ovulatory phase of menstrual cycle.

Solution

The number of oogonial cells is the highest before a human female is born, lesser at the time of birth and least at the time of puberty.

Q38. The external sphincter of the urethra shows the presence of which type of cells?

• Smooth muscle
• Striated muscle
• Ligaments
• Connective tissue

Solution

The external sphincter of the urethra shows the presence of striated muscle fibres around its membranous part, while the internal sphincter shows the presence of smooth muscle fibres at its beginning.

Q39. Morula is a developmental stage:

• Between the zygote and blastocyst
• Between the blastocyst and gastrula
• After the implantation
• Between implantation and parturition

Solution

Morula is a developmental stage between the zygote and blastocyst. It consists of 16-32 cells.

Q40. The cell organelle which forms the acrosome of the sperm is

• Golgi apparatus
• Vacuole
• Nucleus
• Cytoplasm