Write notes on—
(a) Adam’s apple.
(b) Secondary sexual characters.
(c) Sex determination in the unborn baby.

The table below shows the data on likely heights of boys and girls as they grow in age. Draw graphs showing height and age for both boys and girls on the same graph paper. What conclusions can be drawn from these graphs?

During adolescence, the body of boys and girls undergoes certain changes. Given below are few of those changes
(a) Broad shoulders
(b) Wider chests
(c) Wider region below waist
(d) Development of muscles
(e) Development of mammary glands
(f) Growth of facial hair
(g) Acne and pimples on face
(h) Development of sex organs
(i) High-pitched voice
(j) Growth of pubic hair
Categorise these changes into those that occur in boys and those that occur in girls and fill in the table given below.
Body changes during adolescence

In figure, mark the position of the endocrine glands which release the hormones that
(a) control the release of sex hormones.
(b) are responsible for the secondary sexual characters in boys.
(c) prevent diabetes.
(d) maintain the correct salt balance in the blood.

It is believed that height of a child depends upon the genes inherited from parents. However, it is often seen that tall parents may have short children and vice-versa. Are these factors other than genes that can cause these variations?

Word game : Use the clues to work out the words.
Across:
(3) Protruding voice box in boys
(4) Glands without ducts
(7) Endocrine gland attached to brain
(8) Secretion of endocrine glands
(9) Pancreatic hormone
(10) Female hormone
Down:
(1) Male hormone
(2) Secretes thyroxine
(3) Teenage
(5) Hormone reaches here through blood stream
(6) Voice box
(7) Changes at adolescence constitute