Question

a)Define the term Endocrine system.
b) Write four endocrine glands along with hormone secreted by them and their functions.
c)Mention the secondary sexual characters in males and females.​

Answer 1

Answer a.)

Endocrine glands:

Endocrine glands are ductless glands which pour their secretion directly into bloodstream.

• They called ductless glands because their secretions are poured directly into the blood not through any special duct.

Answer b.)

Four endocrine glands in human body are as follows:

1. The pituitary gland:

➛ It releases many hormones that control other endocrine glands. One of these, the growth hormone has marked influence on the growth of the body.

Function:

• This gland has many regulatory functions and therefore also referred to as the "master gland".
• It produces hormones which control growth. Too large an amount of these hormones cause gigantism while to little causes dwarfism.

2. The Thyroid gland:

➛ It reduces in iodine containing hormone called thyroxine hormone.

Function:

• It has a major influence on physical and mental development after birth by controlling the rate of chemical reactions in all cells.

3. The Adrenal gland:

➛ The adrenal medulla produces the hormone Adrenaline or epinephrine.

Function:

• This hormone is also called emergency hormone because it is released into the body in greater amounts during highly emotional states such as anger or fear.
• It also secretes hormones which maintain the correct salt balance in the body.

4. The Pancreas:

➛ It secretes two hormones insulin and glucagon.

Function:

• It contains cluster of cells called islets of langerhans which produce two secretions affecting the metabolism of glucose that is blood sugar

1. Insulin: It lowers the blood sugar level.
2. Glucagon: It raises the blood sugar level.

Answer c.)

All the features which help to distinguish the male from the female they are called secondary séxual characters.

I.) In females:

• Enlargement of breast.
• Gírls start menstruation at around this time.
• Long bone growth stops.
• Enlargement of hips.
• Waistline narrows.

II.) In males:

• Appearance of beard and moustaches.
• Deepening of the voice.
• Broadening of shoulders.
• Sperm production begins.
• Muscles develop.

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