Explanation

• An atom is the smallest possible particle of an element that can combine to form new compounds.
• Atoms are the building blocks of matter, and they cannot be broken down into smaller particles.

Last verified on 15-03-2026

Explanation

• A molecule is the smallest particle of a substance that retains its chemical properties.
• It is made of two or more atoms chemically bonded together.
• Examples of molecules: H₂O, O₂, CO₂, NH₃, CH₄.

Additional information:

• An atom is the smallest unit of an element.
• A compound is a substance formed when different elements combine chemically.

Last verified on 13-03-2026

Explanation

• Conduction is the process of heat transfer through direct contact of molecules.
• In solids, especially metals, molecules vibrate and pass energy to neighboring molecules.
• No movement of the substance itself is required; only energy is transferred.

Last verified on 13-03-2026

Explanation

• Green plants use carbon dioxide (CO₂) from the atmosphere to make food via photosynthesis.
• In photosynthesis, CO₂ + H₂O → Glucose + O₂ (with sunlight and chlorophyll).

Last verified on 13-03-2026

Explanation

• Sublimation is the direct transition of a solid into a gas without passing through the liquid phase.

Additional information:

Some common sublimating substances:

• Dry ice (CO₂) – solid → gas
• Iodine crystals – solid → violet gas
• Camphor – solid → vapor
• Naphthalene (mothballs) – solid → gas
• Ammonium chloride – solid → gas

Last verified on 13-03-2026

Explanation

• Glucose is a simple sugar (monosaccharide) and a primary source of energy for cells.
• Its chemical formula is C6H12O6.

Additional information:

• Fructose: C6H12O6 (same formula as glucose, different structure)
• Galactose: C6H12O6
• Ribose: C5H10O5
• Deoxyribose: C5H10O4
• Sucrose (disaccharide): C12H22O11

Last verified on 13-03-2026

Explanation

• Hydrochloric acid (HCl) is produced in the stomach, not the liver.
• The Right lobe, Hepatocyte, Common bile duct are directly associated with the liver.
• The liver is involved in bile production, metabolism, and detoxification.

Last verified on 13-03-2026

Explanation

• Mitochondria are known as the powerhouse of the cell.
• They are the site of cellular respiration, where glucose is converted into ATP (energy).
• Mitochondria have a double membrane and their own DNA and ribosomes.
• They provide energy for all cell activities.

Last verified on 13-03-2026

Explanation

• Chromosomes are thread-like structures inside the nucleus that carry genetic material (DNA).
• They determine an organism’s hereditary traits.
• Humans have 46 chromosomes arranged in 23 pairs.

Last verified on 13-03-2026

Explanation

• The diaphragm of a microscope controls the amount of light passing through the specimen.
• In humans, the iris regulates the amount of light entering the eye through the pupil.

Additional information:

• Eyepiece → Lens of eye (focuses image)
• Stage → Retina (holds specimen/image for observation)
• Light source → Pupil (allows light to enter)
• Objective lens → Cornea & Lens (magnifies object)

Last verified on 13-03-2026