Explanation

• Macronutrients are the nutrients that are needed in the highest concentration by living organisms.
• They include carbohydrates, proteins, and fats, which provide energy and support growth and maintenance of tissues.

Last verified on 08-11-2026

Explanation

• The majority of nutrient absorption in the digestive system occurs in the small intestine,
• Where the final stages of digestion take place.
• This organ's structure, featuring villi and microvilli, creates a large surface area optimized for absorbing digested nutrients and most water into the bloodstream.

Last verified on 08-11-2026

Explanation

• Mitosis produces two genetically identical daughter cells from one parent cell.
• Each daughter cell receives the same number of chromosomes as the parent cell.
• Mitosis is important for growth, tissue repair, and replacement of damaged or old cells.

Last verified on 08-11-2026

Explanation

• Guard cells are specialized cells that surround each stoma and regulate its opening and closing.
• When guard cells absorb water and become turgid, the stomata open.
• When guard cells lose water and become flaccid, the stomata close.
• This process regulates gas exchange and water loss through transpiration.

Last verified on 08-11-2026

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

Integrated Circuit (IC)

• - Definition: A small electronic circuit built on a single semiconductor chip.
• - Material: Usually silicon.
• - Components: Transistors, diodes, and resistors.
• - Purpose: Performs electronic functions in modern devices.
• - Uses: Computers, mobile phones, and calculators.

Last updated 06 Nov 2026 by NA

Explanation

• A Decomposition Reaction is a type of chemical reaction where a single compound breaks down into two or more simpler substances.
• This is the opposite of a Combination Reaction, where two or more substances combine to form a new compound.

Last verified on 07-11-2026

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

Water molecules are held together by hydrogen bonds,

It is a type of strong intermolecular force

Where the slightly positive hydrogen of one molecule attracts the slightly negative oxygen of another, creating a "sticky" network that gives water unique properties like surface tension.

Explanation

• The female gametophyte of angiospermic plants is the embryo sac.
• It is also known as the megagametophyte.
• It is the haploid (containing one set of chromosomes) structure within the ovule that contains the egg cell.
• It is responsible for fertilization.

Last verified on 06-11-2026