Explanation

• Smallest bone: Stapes.
• Location: Middle ear.
• Three ear bones: Malleus, Incus, Stapes.

Additional information:

• Longest bone: Femur (thigh bone).
• Adult human skeleton: Usually 206 bones.
• Newborn: About 300 bones at birth; many later fuse together.
• Human skull: 22 bones (8 cranial + 14 facial)

Last verified on 03-09-2026

Explanation

• Diffusion is the natural movement of particles from an area of higher concentration to lower concentration without external force.
• It occurs in gases, liquids, and even solids to some extent.

Last verified on 14-10-2026

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

• Genetics: Study of heredity and variation in organisms.
• An Austrian monk who experimented with pea plants in the 19th century is known as the "Father of Modern Genetics"

Additional information

• Ecology: Study of organisms and their environment.
• Anatomy: Study of the structure of organisms.
• Evolution: Study of how living organisms change over generations.

Explanation

• The part of the eye that controls the amount of light entering is the Iris.
• It adjusts the size of the pupil according to light intensity.
• In bright light, it reduces light entry; in dim light, it allows more light in.
• This process protects the retina and helps clear vision.

Last verified on 17-05-2026