Explanation

Substances that do not normally sublime

• - Glucose: Decomposes on heating.
• - Sodium chloride: Does not sublime under ordinary laboratory conditions.

Additional information:

• Iodine: Sublimes on heating.
• Camphor: Sublimes easily.

 Last updated on 12 NOV 2026

Explanation

• GPS (Global Positioning System) is used for identifying the location of objects on Earth.
• GPS provides accurate positioning and timing information, enabling users to determine their precise location anywhere on Earth.
• It is a network of satellites orbiting the Earth.
• It provide location information and timing signals to GPS receivers on the ground.

Last verified on 12-11-2026

Explanation

• Chlorophyll is the green pigment responsible for photosynthesis in plants.
• It captures sunlight and converts it into chemical energy to make food.

• Plants use chlorophyll to produce glucose and oxygen through photosynthesis.
• Chloroplasts contain chlorophyll a and b, which absorb sunlight.

Last verified on 22-01-2026

Explanation

• Mitochondria are called the powerhouse of the cell.
• Because they produce Adenosine Triphosphate (ATP).
• ATP is the energy currency of the cell.
• ATP provides energy for different cellular activities such as movement, growth, and transport.
• Energy is produced through aerobic cellular respiration using oxygen and الغذائی molecules.
• They are found in the cytoplasm of most eukaryotic cells.
• Richard Altmann first described mitochondria in 1890.

Main Parts of a Cell:

1. Cell membrane → Outer protective layer
2. Nucleus → Controls cell activities
3. Cytoplasm → Jelly-like material between membrane and nucleus

Last verified on 09-05-2026

Explanation

• The SI unit of energy is the Joule (J).
• It is the unit of energy, work, and heat.

Additional information:

• 1 Joule (J) = 1 Newton × 1 meter
• Calorie – 1 cal = 4.184 J
• Kilowatt-hour (kWh) – 1 kWh = 3.6 × 10⁶ J
• Electronvolt (eV) – 1 eV ≈ 1.602 × 10⁻¹⁹ J
• Erg (CGS unit) – 1 erg = 10⁻⁷ J

Last verified on 17-01-2026

Explanation

• During the daytime, plants require Carbon Dioxide (CO2) for photosynthesis.
• Which is the process by which they produce glucose and oxygen.

Last updated by NA on 05-11-2026

Explanation

• Predator-prey: One organism (the predator) hunts, kills, and directly eats another living organism (the prey) for food.
• Example: A lion hunting and eating a zebra.

Additional information:

• Parasitism: One organism (the parasite) lives on or inside another organism (the host) and feeds off it. It harms the host but usually does not kill it right away.
• Example: Fleas drinking blood from a dog.
• Mutualism: A close relationship where both organisms help each other and benefit.
• Example: Bees collecting nectar while pollinating flowers.

Last verified on 16-10-2026

Explanation

• Leaves are called the food factory of plants.
• They prepare food through the process of Photosynthesis.
• Chlorophyll in leaves absorbs sunlight to make food.
• Photosynthesis uses Carbon dioxide (CO₂), Water (H₂O), and Sunlight.
• Food produced is mainly Glucose, which provides energy to the plant.

Last verified on 13-03-2026

Explanation

• Sublimation is the process in which a solid directly changes into a gas without passing through a liquid phase.
• This endothermic phase transition
• Occurs when a substance absorbs enough energy to overcome intermolecular forces.
• Deposition: Gas to Solid (the reverse process).
• Examples: Dry ice, iodine, frost/snow.

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