Biology

Human Reproductive System

751 Questions

The human reproductive system covers the anatomy of reproductive organs, gamete production, fertilization processes, and reproductive technologies. This is a highly scoring area in biology sections of competitive exams. Use these questions to practice key concepts.

Fertilization processGamete productionReproductive organ functionsAssisted reproductive technology

Human Reproductive System Questions

Multiple choice

MIS stands for Mullerian Inhibiting Substance, which is a gonadal hormone with multiple functions. It is secreted by which among the following parts of the male reproductive system?

  1. Cells of Cowper's glands

  2. Cells of the seminal vesicles

  3. Cells of the sertoli cells

  4. Cells of the leydig cells

  5. Cells of prostate gland
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

A Sertoli cell is a 'nurse' cell of the testes. The MIS glycoprotein is produced by Sertoli cells of the testes during fetal and neo-natal life in males.

Multiple choice

Which among the following can be excluded from the function of Sertoli cells?

  1. Aromatisation of androgen precursors to estrogen

  2. Maintenance of the blood-testis barrier

  3. Maintenance of the position of primordial germ cells against the basement membrane

  4. Synthesis of inhibin andantimullerian hormone

  5. Metabolic support of developing spermatozoa

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Primordial germ cells are maintained against the basement membrane of the seminiferous tubules; Sertoli cells do not appear to have a role in this process.

Multiple choice

Which of the following is unlikely to be a consequence of testicular growth in males?

  1. Decreased in the production of Müllerian inhibiting substance

  2. Occurence of spermatogenesis in many structures of the male reproductive system

  3. Leydig cell stimulation

  4. Initiation of spermatogenesis  

  5. Increased mass of seminiferous tubules
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Mullerian inhibiting substance (MIS) is responsible for causing the mullerian ducts to degenerate, accounting for the sole development of male internal genitalia in a fetus with a functional testis. If it is absent during fetal development, female internal genitalia would develop by default

Multiple choice

The human sperm is equipped with proteolytic enzymes capable to digest the zona pellucida. These enzymes are located at

  1. cumulus

  2. acrosome

  3. corona

  4. head

  5. foreskin
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The acrosome is the part of the sperm containing proteolytic enzymes to digest the zona pellucida. It is exposed by the process of capacitation. Then, under the influence of substances released by corona radiata cells, it releases its proteolytic enzymes and penetrates the oocyte.

Multiple choice

Which of the following plays a crucial role in determining the sex of the offspring in mammals?

  1. Spermatogonium

  2. Spermatozoon

  3. Spermatids

  4. Secondary spermatocytes

  5. Primary spermatocytes
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

A spermatozoon is a motile sperm cell or moving form of the haploid cell that is the male gamete. A spermatozoon joins an ovum to form a zygote. In mammals, the sex of the offspring is determined by the sperm cell: a spermatozoon bearing a Y chromosome will lead to a male (XY) offspring, while one bearing an X chromosome will lead to a female (XX) offspring.

Multiple choice

The epididymis is a long, coiled tube that stores sperm and transports it from the testes. Which of the following cells of epididymis are regarded as the undifferentiated precursors of principal cells in human males?

  1. Paradidymis

  2. Stereocilia

  3. Apical cells

  4. Basal cells

  5. Main cells
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Basal cells are the shorter, pyramid-shaped cells which contact the basal lamina but taper off before their apical surfaces reach the lumen.

Multiple choice

In mammals, fertilization takes place in the

  1. follicle

  2. fallopian tubes

  3. testis

  4. vagina
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Fertilization occurs in the fallopian tubes, where sperm meets the egg after ovulation. The fertilized egg (zygote) then travels to the uterus for implantation. The follicle releases the egg in the ovary, the vagina is the birth canal, and testis is a male reproductive organ.

Multiple choice

The developing gonads can be identified as either male or female by the end of the

  1. 9th week of development

  2. 7th week of development

  3. 5th week of development

  4. 11th week of development
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Gonadal sexual differentiation begins during the 7th week of embryonic development. The bipotential gonad develops into either testes or ovaries based on genetic and hormonal signals. Earlier stages (5th week) have undifferentiated gonads, while 9th and 11th weeks are too late - differentiation is typically complete or well underway.

Multiple choice

The ovary after fertilization is converted into

  1. embryo

  2. endosperm

  3. fruit

  4. seed
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

After fertilization, the ovary develops into the fruit while the ovules become seeds. The embryo develops from the zygote, and endosperm is the nutritive tissue formed from double fertilization. This is a fundamental concept in plant life cycles.

Multiple choice

The process of double fertilisation means

  1. fusion of two male gametes with an egg nucleus

  2. fusion of two polar nuclei

  3. fusion of sperm nucleus with secondary nucleus

  4. fusion of one sperm nucleus with the egg nucleus and the other sperm nucleus with the definitive nucleus
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The process of double fertilisation means fusion of one sperm nucleus with the egg nucleus and the other sperm nucleus with the definitive nucleus. 

Multiple choice

If the testis fail to descend in scrotal sacs, the condition is called

  1. Cryptorchidism

  2. Hernia

  3. Castrection

  4. Both (b) and (c)

  5. None of these
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Cryptorchidism is the medical term for undescended testicles, where one or both testes fail to move down into the scrotum. This is different from hernia (protrusion of organ) or castration (removal of testes).