Control and Coordination | Class 10 Science Notes

Functions of Hormones

Hormones perform diverse functions essential for growth, development, and homeostasis. The pituitary gland secretes growth hormone, which stimulates growth in all organs. The thyroid gland produces thyroxin, regulating metabolism to provide energy for growth. Insulin from the pancreas controls blood sugar levels by facilitating glucose uptake by cells. Testosterone from the testes promotes male sexual development and secondary sexual characteristics, while oestrogen from the ovaries regulates female reproductive functions and menstrual cycles. Adrenaline from the adrenal glands prepares the body for emergency situations by increasing heart rate and breathing. Releasing hormones from the hypothalamus stimulate the pituitary gland to release other hormones. Hormones act at specific target organs and their secretion is tightly regulated by feedback mechanisms to maintain balance. For example, insufficient growth hormone causes dwarfism, while excess can lead to gigantism. Iodine deficiency affects thyroxin production, causing goitre. Hormonal imbalances can lead to diseases like diabetes, which is treated by insulin injections. Thus, hormones are vital for coordinated functioning and health.

📊 Diagram: Table on page 12 listing hormones, their glands, and functions

🧪 Activity: Activity 6.4: Completing the table of hormones, their endocrine glands, and functions.

🔗 Connection: This section prepares students for the summary and exercises on control and coordination mechanisms in animals and plants.

Table on page 12 (8×4)