Explanation

Non-renewable energy sources:

• Oil
  
• Nuclear energy
• Petroleum
• Natural gas & coal

Renewable sources of energy:

• Solar energy
• Wind energy
• Hydroelectric power
• Biomass energy
• Geothermal energy
• Tidal energy

Last verified on 11-02-2026

Explanation

• Photosynthesis is the process by which green plants make their own food using sunlight, water, and carbon dioxide.
• It occurs in chloroplasts of plant cells.
• The process starts with light-dependent reactions, which capture solar energy to produce energy-rich molecules.

Last verified on 11-02-2026

Explanation

• After fertilization, the ovary develops into a fruit, enclosing the seeds.
• Meanwhile, each ovule inside the ovary develops into a seed.

Last verified on 11-02-2026

Explanation

• Accumulation of CO2 in the atmosphere traps heat from the sun, causing the Greenhouse effect.
• This leads to global warming and climate change.

Additional information:

Other effects of high CO2:

• Melting of glaciers, rising sea levels
• Altered weather patterns

Last verified on 11-02-2026

Explanation

• Chloroplast is the plant cell organelle that performs photosynthesis.
• It contains chlorophyll, the green pigment that captures sunlight to produce food (glucose) for the plant.

Additional information:

• Mitochondria: Powerhouse of the cell, produces energy via respiration
• Nucleus: Controls cell activities and stores DNA

Last verified on 11-02-2026

Explanation

• Economically important traits in plants, like yield, height, fruit size, are influenced by the environment.
• These are polygenic traits, controlled by multiple genes and showing continuous variation.

Additional information:

• Monogenic traits: Controlled by a single gene, less affected by environment

Last verified on 11-02-2026

Explanation

• Programmed cell death is known as apoptosis.
• It is a controlled process that allows the body to eliminate damaged or unnecessary cells without causing inflammation.

Last verified on 11-02-2026

Explanation

• Quantitative traits are measurable traits like height, weight, or milk production.
• They show continuous variation, meaning a range of values rather than distinct categories.

Additional information:

• Discontinuous variation: Traits with distinct categories (e.g., blood group, seed shape)

Last verified on 11-02-2026

Explanation

• Essential amino acids are those mammals cannot synthesize on their own.
• They must be obtained from the diet.
• Examples include lysine, leucine, valine, tryptophan.

Last verified on 11-02-2026

Explanation

• Antibiotics are mainly produced by microorganisms such as bacteria and fungi.
• They are used to kill or stop the growth of harmful bacteria.
• Many antibiotics are discovered from soil microbes.

Last verified on 11-02-2026