Human Body and Health

Overview

Human Body and Health is a core component of Environmental Studies (EVS) in TS TET Paper I, designed for candidates aspiring to teach classes 1-5. This topic tests your understanding of how the human body functions, the importance of balanced nutrition, common diseases affecting children, and basic hygiene practices. Since EVS integrates science with daily life, examiners frequently frame questions around practical scenarios—what a child should eat, how diseases spread, or why handwashing matters.

For the exam, you must know the major organ systems (their parts and functions), nutritional requirements at different ages, causes and prevention of common childhood diseases, and hygiene habits that promote health. Questions often appear as application-based MCQs where you identify a deficiency disease from symptoms or choose the correct hygiene practice. Mastering this topic also helps in pedagogy questions about teaching health education through activities.

Key Concepts

• **Organ systems work together**: The human body has interdependent systems—digestive, respiratory, circulatory, excretory, skeletal, muscular, and nervous—each performing specific functions but relying on others for overall health.

• **Nutrition is about balance, not just food**: A balanced diet includes carbohydrates, proteins, fats, vitamins, minerals, water, and roughage in appropriate proportions based on age, activity, and health status.

• **Deficiency diseases arise from nutritional gaps**: Lack of specific nutrients causes identifiable diseases—iron deficiency causes anaemia, Vitamin A deficiency causes night blindness, and so on.

• **Communicable vs non-communicable diseases**: Communicable diseases spread through air, water, food, or contact (malaria, typhoid), while non-communicable diseases do not spread person-to-person (diabetes, anaemia).

• **Hygiene prevents disease transmission**: Personal hygiene (handwashing, bathing) and environmental hygiene (clean water, waste disposal) break the chain of infection.

• **Vaccination builds immunity**: Immunisation protects children from preventable diseases like polio, measles, and tetanus through scheduled doses.

• **First aid is immediate care**: Basic knowledge of first aid for cuts, burns, fractures, and bites is essential for teachers handling young children.

Key Facts

| Category | Must-Remember Facts | |----------|---------------------| | **Digestive System** | Mouth → Oesophagus → Stomach → Small intestine (absorption) → Large intestine → Rectum. Saliva begins starch digestion. | | **Respiratory System** | Nose → Trachea → Bronchi → Lungs (alveoli). Oxygen absorbed, carbon dioxide expelled. | | **Circulatory System** | Heart pumps blood; arteries carry oxygenated blood (except pulmonary artery); veins carry deoxygenated blood (except pulmonary vein). | | **Excretory System** | Kidneys filter blood to produce urine; skin excretes sweat; lungs expel CO₂. | | **Skeletal System** | 206 bones in adults; protects organs, provides structure, produces blood cells in bone marrow. | | **Nervous System** | Brain, spinal cord, and nerves; controls voluntary and involuntary actions. |

**Nutrition Facts**:

• Carbohydrates: Energy source (rice, wheat, potatoes)
• Proteins: Body building (pulses, eggs, milk)
• Fats: Stored energy, insulation (oil, butter, nuts)
• Vitamins: Regulate body processes (A, B, C, D, E, K)
• Minerals: Calcium (bones), Iron (blood), Iodine (thyroid)
• Roughage/Fibre: Aids digestion (vegetables, whole grains)
• Water: 70% of body weight; regulates temperature

**Common Deficiency Diseases**: | Deficiency | Disease | Symptoms | |------------|---------|----------| | Vitamin A | Night blindness | Poor vision in dim light | | Vitamin B1 | Beri-beri | Weakness, nerve damage | | Vitamin C | Scurvy | Bleeding gums, weakness | | Vitamin D | Rickets | Soft, bent bones in children | | Iron | Anaemia | Fatigue, pale skin | | Iodine | Goitre | Swollen thyroid gland | | Protein | Kwashiorkor | Swollen belly, weak muscles | | Protein-Energy | Marasmus | Severe weight loss, weakness |

**Common Communicable Diseases**:

• Malaria: Mosquito bite (Anopheles); fever, chills
• Dengue: Mosquito bite (Aedes); high fever, joint pain
• Typhoid: Contaminated water/food; prolonged fever
• Cholera: Contaminated water; severe diarrhoea
• Tuberculosis (TB): Airborne; persistent cough, weight loss
• COVID-19: Respiratory droplets; fever, cough, breathlessness

Worked Examples

**Example 1**: A 7-year-old child complains of difficulty seeing clearly at dusk and night. Which nutrient deficiency is most likely, and what foods should be recommended?

*Solution*:

• Symptom: Poor vision in dim light = Night blindness
• Deficiency: Vitamin A
• Food sources: Carrots, papaya, mango, green leafy vegetables, eggs, fish liver oil
• Prevention: Include yellow-orange fruits and dark green vegetables in daily diet

**Example 2**: In a village school, several children develop fever, diarrhoea, and vomiting after drinking water from a common source. Identify the likely cause and suggest preventive measures.

*Solution*:

• Likely disease: Cholera or Typhoid (waterborne)
• Cause: Contaminated drinking water
• Prevention measures:

1. Boil or filter water before drinking 2. Use chlorine tablets for purification 3. Avoid open defecation; use toilets 4. Wash hands before eating and after using toilet 5. Keep water storage containers covered and clean

**Example 3**: Match the organ system with its primary function:

• Circulatory system → ?
• Excretory system → ?

*Solution*:

• Circulatory system → Transports oxygen, nutrients, and hormones throughout the body
• Excretory system → Removes waste products (urine, sweat, CO₂) from the body

Common Mistakes

• **Confusing arteries and veins**: Students assume arteries always carry pure blood. *Correction*: Arteries carry blood away from heart; pulmonary artery carries deoxygenated blood to lungs.

• **Mixing up Kwashiorkor and Marasmus**: Both are protein-energy malnutrition but differ in presentation. *Correction*: Kwashiorkor = swollen belly, some fat retained; Marasmus = severe wasting, no fat.

• **Believing all vitamins come from fruits only**: *Correction*: Vitamin D comes from sunlight and fish; Vitamin K from green vegetables; B12 from animal products.

• **Thinking hygiene is only about bathing**: *Correction*: Hygiene includes handwashing, nail trimming, dental care, clean clothes, and environmental cleanliness.

• **Confusing immunisation with treatment**: *Correction*: Vaccination prevents disease before infection; it does not cure existing disease.

Quick Reference

• **6 nutrients + water**: Carbohydrates, proteins, fats, vitamins, minerals, roughage, and water make a balanced diet.

• **Vitamin A → Night blindness; Vitamin D → Rickets; Iron → Anaemia; Iodine → Goitre**.

• **Waterborne diseases**: Cholera, Typhoid, Jaundice—prevented by safe drinking water.

• **Vector-borne diseases**: Malaria (Anopheles mosquito), Dengue (Aedes mosquito).

• **ORS (Oral Rehydration Solution)**: Salt + Sugar + Water—first aid for diarrhoea and dehydration.

• **Pulse Polio, BCG, DPT**: Key vaccines in India's Universal Immunisation Programme.