Hormones
Introduction
Hormones are chemical messengers secreted by endocrine glands that regulate various physiological processes in the body.
They act at distant organs, travel through bloodstream, and control growth, metabolism, reproduction, and mood.
In Bihar, issues like thyroid disorders, diabetes, and malnutrition have direct links with hormonal imbalances.
Characteristics of Hormones
- Secreted by ductless glands (endocrine system)
- Act in very small amounts
- Travel via blood to target organs
- Regulate long-term changes: growth, mood, puberty, metabolism
- Are specific in action (lock-key mechanism)
๐ PYQ (CDPO): What are hormones? โ Chemical messengers
๐ Expected MCQ: Hormones are secreted by...? โ Endocrine glands
Major Hormones & Their Functions
1. Pituitary Gland ("Master gland")
- Located at base of brain
- Secretes:
- Growth Hormone (GH) โ Height & growth
- TSH โ Stimulates thyroid
- FSH, LH โ Reproduction control
2. Thyroid Gland
- Located in neck
- Secretes Thyroxine โ Controls metabolism
- Needs iodine for function
- Deficiency โ Goitre (common in rural Bihar)
3. Adrenal Glands
- On kidneys
- Secretes:
- Adrenaline โ Fight or flight (stress) hormone
- Cortisol โ Manages stress, immune function
4. Pancreas
- Secretes:
- Insulin โ Lowers blood sugar
- Glucagon โ Raises blood sugar
- Diabetes = Insulin deficiency
5. Ovaries (in females)
- Secrete Estrogen and Progesterone
- Regulate menstrual cycle, pregnancy traits
6. Testes (in males)
- Secrete Testosterone
- Controls male sexual traits, muscle development
๐ PYQ (BPSC): Deficiency of which hormone causes diabetes? โ Insulin
๐ Expected MCQ: Which hormone regulates metabolism? โ Thyroxine
Hormonal Diseases & Deficiency Disorders
| Hormone | Disorder |
|---|---|
| Growth Hormone | Dwarfism or Gigantism |
| Insulin | Diabetes (Hyperglycemia) |
| Thyroxine | Goitre, Mental Retardation in kids |
| Estrogen | Menstrual issues, infertility |
| Testosterone | Delayed puberty in males |
๐ Expected MCQ: Goitre is caused due to deficiency of? โ Thyroxine
๐ PYQ (CDPO): Which hormone controls sugar levels? โ Insulin
Hormonal Imbalance in Bihar Context
- Thyroid disorders common in districts with iodine-deficient soils
- Diabetes prevalence rising in urban Bihar due to lifestyle changes
- Anaemia in women often linked to menstrual hormone imbalance
- ICDS & POSHAN Abhiyaan aim to address hormonal malnutrition among children and women
- School Health Campaigns include goitre check-ups and awareness
๐ Expected MCQ: POSHAN Abhiyaan helps in...? โ Fighting hormonal malnutrition
Hormones vs Enzymes
| Feature | Hormones | Enzymes |
|---|---|---|
| Secreted by | Endocrine glands | Exocrine glands/cells |
| Action | Regulate body functions | Catalyze biochemical reactions |
| Target | Distant organs | Local molecules |
| Example | Insulin, Thyroxine | Amylase, Pepsin |
๐ Expected MCQ: Which among the following is a hormone? โ Insulin
PYQs + Expected MCQs
๐ PYQ (BPSC): What is the function of insulin? โ Lowers blood sugar
๐ PYQ (CDPO): Which gland secretes adrenaline? โ Adrenal gland
๐ Expected MCQ: Which hormone is responsible for male features? โ Testosterone
๐ Expected MCQ: Master gland of the body? โ Pituitary gland
๐ Expected MCQ: Deficiency of which hormone causes dwarfism? โ Growth Hormone
Quick Revision Points
- Hormones = chemical messengers, secreted by endocrine glands
- Insulin โ Sugar control, Thyroxine โ Metabolism, GH โ Height
- Adrenaline โ Emergency hormone, Estrogen/Testosterone โ Sex hormones
- Bihar: Thyroid & diabetes rising, addressed via POSHAN, ICDS, Mid-Day Meal
- Difference: Hormones regulate โ Enzymes catalyze
Sources Used
- NCERT Class 10 Science โ Control & Coordination
- Lucent GK โ Biology Section
- Drishti Quick Book โ Science
- BPSC PYQs โ Ghatna Chakra, EduTeria
- Ministry of Health โ POSHAN & NHM Reports
- School Health Programme Bihar
- UNICEF Bihar โ Anaemia & Iodine Reports