Male Reproductive System

Question 1

What is reproduction?

Answer 1

Reproduction is the production of young ones by an organism.

Question 2

What type of reproduction do humans follow?

Answer 2

Humans are sexually reproducing and viviparous (give birth to live young).

Question 3

What are the four main components of the male reproductive system?

Answer 3

Paired testes, Accessory ducts, Accessory glands, and External genitalia (penis).

Question 4

What are the functions of the testes?

Answer 4

Produce sperm and secrete testosterone.

Question 5

Where are the testes formed, and when do they descend?

Answer 5

Formed in the abdomen, descend into the scrotum at birth or by the 8th month of pregnancy.

Question 6

Why is the scrotum important for sperm production?

Answer 6

It maintains a temperature 2-2.5°C lower than body temperature, which is essential for spermatogenesis.

Question 7

What are the dimensions of each testis?

Answer 7

Length: 4-5 cm, Width: 2-3 cm.

Question 8

How many lobules are in each testis?

Answer 8

About 250 lobules per testis.

Question 9

What is present inside each lobule?

Answer 9

1-3 coiled seminiferous tubules.

Question 10

What type of cells line the seminiferous tubules?

Answer 10

1. Male germ cells (spermatogonia) – Develop into sperm.
2. Sertoli cells – Provide nutrition to germ cells.

Question 11

What is found outside the seminiferous tubules?

Answer 11

Interstitial spaces containing Leydig cells, blood vessels, and immune cells.

Question 12

What is the function of Leydig cells?

Answer 12

Secrete androgens (testosterone).

Question 13

What are the accessory ducts in order of sperm transport?

Answer 13

Seminiferous tubules → Rete testis → Vasa efferentia → Epididymis → Vas deferens → Ejaculatory duct → Urethra → Urethral meatus.

Question 14

What is the function of the epididymis?

Answer 14

Stores sperm temporarily and helps in maturation.

Question 15

What does the urethra receive?

Answer 15

Ducts of the prostate and Cowper’s glands.

Question 16

What are the three accessory glands?

Answer 16

Prostate gland, Seminal vesicles (pair), and Cowper’s glands (pair).

Question 17

What is the collective secretion of these glands called?

Answer 17

Seminal plasma.

Question 18

What is the composition of seminal plasma?

Answer 18

Rich in fructose, calcium, and enzymes.

Question 19

What does seminal plasma + sperm form?

Answer 19

Semen.

Question 20

What are the functions of seminal plasma?

Answer 20

1. Helps in sperm transport.
2. Supplies nutrients to sperm.
3. Provides alkalinity to neutralize the acidic environment of the uterus.

Question 21

What is the role of Cowper’s glands?

Answer 21

Lubricate the penis.

Question 22

What helps in sperm maturation and motility?

Answer 22

Secretions from the epididymis, vas deferens, seminal vesicles, and prostate.

Question 23

What is the function of the penis?

Answer 23

Copulatory organ that facilitates insemination.

Question 24

What type of tissue makes up the penis?

Answer 24

Erectile spongy tissue.

Question 25

What causes an erection?

Answer 25

Filling of spongy tissue with blood.

Question 26

What is the tip of the penis called?

Answer 26

Glans penis.

Question 27

What covers the glans penis?

Answer 27

Prepuce (foreskin).

Question 28

What is spermatogenesis, and where does it occur?

Answer 28

Spermatogenesis is the process of sperm formation that occurs in the seminiferous tubules of the testes.

Question 29

What are spermatogonia?

Answer 29

Spermatogonia are diploid male germ cells present on the inner walls of the seminiferous tubules. They multiply by mitotic division.

Question 30

What happens to primary spermatocytes during spermatogenesis?

Answer 30

Primary spermatocytes undergo meiosis. The first meiotic division produces two haploid secondary spermatocytes, each with 23 chromosomes.

Question 31

What are spermatids, and how are they formed?

Answer 31

Spermatids are haploid cells formed after the second meiotic division of secondary spermatocytes. They undergo spermiogenesis to develop into spermatozoa.

Question 32

What is spermiogenesis?

Answer 32

Spermiogenesis is the process where spermatids transform into mature spermatozoa (sperms).

Question 33

What is the function of Sertoli cells in the seminiferous tubules?

Answer 33

Sertoli cells provide nutrition and support to developing spermatogenic cells.

Question 34

Describe the structure of a sperm.

Answer 34

A sperm consists of the head, neck, middle piece, and tail. The head contains the nucleus and acrosome, the middle piece contains mitochondria, and the tail aids in movement.

Question 35

What is the acrosome, and what is its role?

Answer 35

The acrosome is a cap-like structure over the sperm's head. It contains enzymes that help in the penetration of the ovum during fertilization.

Question 36

What is the significance of the middle piece of a sperm?

Answer 36

The middle piece contains mitochondria, which provide energy for the movement of the sperm.

Question 37

How many sperms are released during ejaculation, and what percentage must show normal shape and vigorous motility?

Answer 37

About 200–300 million sperms are released, and at least 60% of them must show normal shape and 40% vigorous motility.

Question 38

What is oogenesis, and how does it differ from spermatogenesis?

Answer 38

Oogenesis is the formation of ova in the ovaries. Unlike spermatogenesis, it begins during embryonic development, pauses, and resumes at puberty.

Question 39

What is the role of gonadotropin-releasing hormone (GnRH) in gametogenesis?

Answer 39

GnRH stimulates the anterior pituitary to release FSH and LH, which regulate spermatogenesis and oogenesis.