Explanation

Chromosomes are made up of:

• Nucleic acid (DNA or RNA)
• Proteins (histones and non-histone proteins)

A chromosome is made up of proteins and DNA organized into genes.

Each cell normally contains 23 pairs of chromosomes.

Explanation

• Apiculture is the practice of rearing honeybees for honey and wax production.
• Helps in pollination and increasing crop yields.
• Honey, beeswax, and propolis are valuable products from apiculture.

• Sericulture → Rearing of silk worms.
• Silviculture → Cultivation of trees and forests.

Last verified on 30-01-2026

Explanation

• Nitrobacter bacteria convert nitrite (NO₂⁻) into nitrate (NO₃⁻) in the soil.
• This is the second step of the nitrification process, which is important for plant nutrition.
• Nitrite is toxic to plants, but nitrate is easily absorbed as a nutrient.

Last verified on 22-01-2026

Explanation

• The young ones of a fly hatch from eggs and are worm-like in appearance.
• These young ones are called Maggots.

Additional information:

Stages of a fly’s life cycle (Complete Metamorphosis):

• Egg – laid on decaying organic matter
• Maggot (larva) – feeding stage
• Pupa – transformation stage
• Adult fly – reproductive stage
• Common fly species – Housefly, Blowfly, Fruit fly

Last verified on 24-01-2026

Explanation

• Insects with complete metamorphosis pass through four stages: egg → larva → pupa → adult.
• The pupa stage is when the insect transforms inside a cocoon or protective casing.

Additional information:

• Pupa stage is also called the resting stage or chrysalis stage

Last verified on 24-01-2026

Explanation

• A flower is made of different parts: Calyx, Corolla, Androecium, and Gynoecium.
• Petals are usually colorful and fragrant to attract pollinators.
• All petals together form a distinct part called the Corolla.

Additional information:

• Calyx is made of sepals, usually green, protecting the bud.
• Gynoecium is the female reproductive part of a flower (carpel/pistil).

Last verified on 23-01-2026

Explanation

• Nutrients required by plants are classified into primary, secondary, and micronutrients.
• Primary nutrients: Nitrogen (N), Phosphorus (P), Potassium (K).

Additional information:

• Secondary nutrients: Calcium (Ca), Magnesium (Mg), Sulfur (S).
• Calcium strengthens cell walls and helps in growth of root and shoot tips.

Last verified on 23-01-2026

Explanation

• Photosynthesis is an endogenic process in plants, meaning it produces energy-rich compounds.
• Requires light, water, and carbon dioxide to produce glucose and oxygen.

Additional information:

• Formula: 6CO₂ + 6H₂O + light → C₆H₁₂O₆ + 6O₂
• Occurs in chloroplasts, primarily using chlorophyll pigments.

Last verified on 23-01-2026

Explanation

• Leaf area reduction occurs when parasites attack a plant, causing loss of tissue or shrinkage.
• This reduction in size or function of the leaf is called atrophy.

Additional information:

• Atrophy reduces photosynthetic efficiency of plants.
• Common causes: parasitic plants, insects, or nutrient deficiencies.

Last verified on 23-01-2026

Explanation

• Tissue death can occur naturally or due to injury, infection, or stress.
• Necrosis is the death of living tissues, often uncontrolled.

Additional information:

• Apoptosis is programmed cell death, a controlled process at the cellular level.
• Plasmolysis is shrinkage of plant cells due to water loss.

Last verified on 23-01-2026