Human Body and Health

Overview

Human Body and Health is a high-scoring and frequently tested topic in UPTET Paper II Science. Questions typically test factual recall of organ functions, disease-nutrient relationships, and system-wise processes. Since this topic directly connects to Environmental Studies (EVS) from Paper I and extends into upper-primary science, examiners expect candidates to demonstrate both content knowledge and the ability to explain bodily functions to Class 6–8 learners.

Mastery requires memorising the sequence of organs in each system, their specific functions, and common disorders. Nutrition-related questions often link deficiency diseases to specific vitamins and minerals. Expect 3–5 direct questions from this area, making it essential for crossing the qualifying threshold.

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Key Concepts

• **Digestive System** converts complex food into simple absorbable nutrients through mechanical (chewing, churning) and chemical (enzyme action) digestion across mouth → oesophagus → stomach → small intestine → large intestine → anus.

• **Respiratory System** facilitates gas exchange — oxygen enters blood and carbon dioxide exits — primarily in the alveoli of lungs; breathing involves inhalation (diaphragm contracts, chest expands) and exhalation (diaphragm relaxes, chest contracts).

• **Circulatory System** is a closed transport network; the heart pumps oxygenated blood through arteries and receives deoxygenated blood through veins; capillaries enable exchange at tissue level.

• **Excretory System** removes metabolic wastes; kidneys filter blood to produce urine containing urea, excess salts and water; other organs (skin, lungs, liver) also excrete waste.

• **Nervous System** coordinates body functions via electrical impulses; consists of Central Nervous System (brain + spinal cord) and Peripheral Nervous System (nerves); reflex actions bypass the brain for speed.

• **Nutrition** involves six essential components — carbohydrates, proteins, fats, vitamins, minerals and water — each serving specific physiological roles.

• **Deficiency Diseases** result from prolonged lack of specific nutrients (e.g., scurvy from Vitamin C deficiency); infectious diseases are caused by pathogens (bacteria, viruses, fungi, protozoa).

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Formulas / Key Facts

| System / Nutrient | Key Fact | |-------------------|----------| | Mouth | Salivary amylase converts starch → maltose | | Stomach | Gastric juice contains HCl and pepsin (protein digestion begins) | | Small Intestine | Maximum absorption of nutrients; villi increase surface area | | Large Intestine | Absorbs water; houses gut bacteria; forms faeces | | Alveoli | Site of O₂–CO₂ exchange; walls one-cell thick | | Heart Chambers | 4 chambers — 2 atria (receive blood), 2 ventricles (pump blood) | | Blood Components | RBCs (carry O₂), WBCs (fight infection), Platelets (clotting), Plasma (liquid) | | Nephron | Functional unit of kidney; performs filtration, reabsorption, secretion | | Neuron | Structural unit of nervous system; dendrite → cell body → axon | | Vitamin A deficiency | Night blindness | | Vitamin B₁ deficiency | Beriberi | | Vitamin C deficiency | Scurvy | | Vitamin D deficiency | Rickets (children), Osteomalacia (adults) | | Iodine deficiency | Goitre | | Iron deficiency | Anaemia | | Protein-energy malnutrition | Kwashiorkor (protein), Marasmus (overall energy) |