Explanation

• Allergy is an abnormal immune response to harmless substances like dust or pollen.
• It occurs when the body reacts excessively to an allergen.
• This reaction involves the immune system producing antibodies.
• Thus, allergy is mainly due to an antigen–antibody reaction.

Last verified on 23-04-2026

Explanation

• A reflex action is a quick, automatic response to a stimulus.
• It is mainly controlled by the spinal cord, which is part of the central nervous system.
• This allows fast response without involving the brain immediately.
• Thus, reflexes are coordinated by the central nervous system.

Last verified on 23-04-2026

Explanation

• The kidney is an important organ responsible for filtering blood and forming urine.
• Its structural and functional unit is the nephron.
• Each kidney contains millions of nephrons.
• They perform filtration, reabsorption, and secretion.

Last verified on 23-04-2026

Explanation

• Oxytocin is the primary hormone responsible for causing the labor pain
• It is often referred to as the "love hormone" or "cuddle chemical,"

Last updated by NA on 22-April-2026

Explanation

• The Earth’s atmosphere is divided into different layers (Troposphere, Mesosphere, and Exosphere).
• Hydrosphere refers to all water bodies on Earth.
• Therefore, Hydrosphere is not part of the atmosphere.

Additional information:

• Troposphere: 0–12 km (weather layer)
• Stratosphere: 12–50 km
• Mesosphere: 50–85 km
• Thermosphere: 85–600 km
• Exosphere: 600 km and above

Last verified on 21-04-2026

Explanation

• Name: Vitamin B-2 (Riboflavin)
• Food sources: Milk, Eggs, Organ meats, Green vegetables, Cereals
• Deficiency causes: Skin problems, sore throat, eye irritation
• Role: Energy production (metabolism)
• Solubility: Water-soluble vitamin

Last verified on 21-04-2026

Explanation

• A barometer measures atmospheric (air) pressure.
• It helps in weather forecasting, detecting storms, and studying climate changes.
• Two common types of barometers: mercury barometer and aneroid barometer.

Last verified on 13-03-2026

Explanation

• A new predator increases predation pressure on prey.
• This leads to a decrease in prey population.
• More prey get hunted and fewer survive.
• Ecosystem balance may temporarily change.
• So, prey population is most directly affected.

Last verified on 12-04-2026

Explanation

• Pepsin is a digestive enzyme in the stomach.
• It works best in strong acidic conditions (low pH).
• This means enzymes have an optimum pH range.
• Outside this range, activity decreases.
• So, it does not work equally at all pH levels.

Last verified on 12-04-2026

Explanation

• Adaptation helps organisms survive in their environment.
• It improves their ability to cope with changes.
• Adapted organisms reproduce more successfully.
• This increases survival chances of the species.
• So, adaptation enhances both survival and reproduction.

Last verified on 12-04-2026