Question

(a) What is puberty? What changes are seen in boys and girls at the time of puberty?
​(b) Draw a neat, labelled diagram of the human male reproductive system and describe it briefly. Why are testes outside the abdominal cavity? What is the role of seminal vesicles and prostrate glands in the human male reproductive system?

Answer 1

(a) Puberty is the process in which the body attains sexual maturity by having well-developed sex organs, and becomes capable of reproduction.

Changes that occur in females during puberty:

(i) development of breasts

(ii) softening of voice

(iii) ovum begins to mature with the onset of puberty.

(iv) occurrence of the menstruation cycle (first menstrual flow beginning at puberty is called menarche, and the stoppage of menstruation at the age of 45 − 50 years is called menopause.)

Changes that occur in males during puberty:

• Under the influence of hormones, the larynx develops prominently. The vocal cord become longer and thicker in boys, causing the voice to become hoarse.
• Growth of hair in other areas of skin like underarms, face, hands, and legs.
• Enlargement of the testicles followed by penis.
• Testes grow and start producing sperms.

(b)

Testes - They are located outside the abdominal cavity within a pouch called the scrotum. The function of the testes is to produce sperms and a hormone called testosterone, which brings about secondary sex characteristics in boys.

Vas deferens - It carries the sperms from the testes to the urethra. It also receives the ducts, which bring products from the seminal vesicles and prostate glands.

Seminal vesicles and prostate glands - The fluids from these organs provide nutrients in the form of fructose, calcium, and some enzymes. The sperms produced in the testes are carried by the vas deferens. The secretions from the seminal vesicles and prostate glands lubricate the sperms.

Testes are located outside the abdominal cavity, within a pouch called the scrotum. For the production of sperms, testes require a temperature that is 2–2.5 °C lower than the temperature of the rest of the body. That is why testes are protected inside the scrotum.

Role of seminal vesicles and prostate gland -

(i) Seminal vesicles - The secretions of seminal vesicles contain many proteins and enzymes and thus provide nutrition to the developing sperms.

(ii) Prostate gland - The prostate gland secretes a slightly alkaline fluid that lubricates the sperms and neutralises the acidity of the vaginal tract.