Explanation

• Olive, nuts, and avocado are rich sources of healthy fats and oils.
• These fats provide energy and help in absorption of fat-soluble vitamins.

Additional information:

• These foods also provide antioxidants, vitamins, and minerals, making them heart-healthy.

Last verified on 27-01-2026

Explanation

• Transpiration is the process by which plants lose water in the form of vapor from leaves, stems, and flowers.
• It helps in cooling the plant, nutrient transport, and maintaining water balance.

Additional information:

• Evaporation: Water loss from soil or water surfaces
• Respiration: Energy release by breaking down sugars
• Photosynthesis: Production of food using sunlight, CO₂, and water

Last verified on 27-01-2026

Explanation

• Spermatophytes are plants that produce seeds and usually bear flowers or cones.
• They are the most advanced group of plants.

Additional information:

• Spermatophytes: Angiosperms (flowering plants) and Gymnosperms
• Bryophytes: Non-vascular, no seeds
• Pteridophytes: Vascular but seedless

Last verified on 27-01-2026

Explanation

Oxygen is a vital component of the Earth's atmosphere (making up about 21%) and is essential for life

Therefore, oxygen is not considered a part of smog.

Smog in Pakistan mainly consists of harmful air pollutants.

These include sulphur dioxide, nitrogen oxides, and carbon monoxide.

Explanation

Tensile strength refers to a material’s ability to resist being pulled apart.

Bones have collagen fibers that provide high tensile strength.

This allows bones to withstand forces that try to stretch or bend them.

Explanation

Christiaan Huygens (1629–1695) proposed the wave theory of light.

He suggested that light travels in the form of waves, not particles.

Huygens’ principle explains how light waves propagate, reflect, and refract.

This theory challenged Newton’s particle theory of light.

Explanation

A covalent bond is formed when two atoms share one or more pairs of electrons.

This sharing creates a strong bond between the atoms, holding molecules together.

Explanation

Bees must collect nectar from approximately 2 million flowers to make 1 pound of honey.

This immense effort requires bees to fly roughly 55,000 to 90,000 miles

A honey bee visits 50 to 100 flowers during a single,, dedicated collection trip.

Production Context: It takes approximately 556 worker bees to gather enough nectar for 1 pound of honey. 

Explanation

Collagen is a structural protein that forms strong fibers in bones.

It provides tensile strength and flexibility, preventing bones from breaking easily.

Collagen works together with calcium phosphate to maintain bone rigidity.

Loss of collagen with age can lead to brittle bones and osteoporosis.

Explanation

Infiltration is the process by which water enters the soil from the surface.

It helps replenish groundwater and maintain soil moisture.

Additional information 

Percolation is the downward movement of water through soil layers.

Evaporation is the conversion of water into vapor, and transpiration is water loss from plants.