C++ | MCQs

Explanation

Chromosomes are thread-like structures made of DNA and proteins, found in the nucleus of eukaryotic cells.

They carry genetic information and ensure its accurate distribution during cell division.

Explanation

Mitosis Stages:

Karyokinesis: Division of the nucleus (prophase, metaphase, anaphase, telophase).

Cytokinesis: Division of the cytoplasm (occurs after karyokinesis).

Explanation

Active Transport:

Requires energy (ATP) to move molecules against the concentration gradient (low → high).

Example: Sodium-potassium pump in cells.

Explanation

Milk is a mixture, not a compound — it contains water, fats, proteins, etc., physically combined.

Chalk (CaCO₃), Ammonia (NH₃), and Table Salt (NaCl) are pure compounds with fixed chemical formulas.

Explanation

The cross product (A × B) is a vector whose magnitude is given by:

| A × B | = |A||B| sinθ

Its direction follows the right-hand rule.

Explanation

The cross product of two vectors A × B ≠ B × A; in fact, A × B = –(B × A), so it is not commutative.

However, it does obey the distributive law over addition, and associative law applies with scalar multiplication but not for three vector cross products.

Explanation

The yellowing of leaves due to lack of chlorophyll is called chlorosis.

This condition occurs when the green pigment, chlorophyll, is reduced or absent in the leaves, causing them to turn yellow. 

Explanation

Chlorophyll, the pigment responsible for photosynthesis in plants, features a porphyrin ring structure at its core.

This ring is composed of four smaller pyrrole rings linked by methine bridges.

A magnesium ion is centrally located within this porphyrin ring, held in place by bonds with nitrogen atoms from the pyrrole rings.

Explanation

The cell wall of oomycetes is made of cellulose. 

Oomycetes, also known as water molds, are distinct from true fungi in that their cell walls are composed primarily of cellulose and glucans, rather than chitin which is the primary component of fungal cell walls.

Explanation

Cyanobacteria utilize phycobilins, specifically phycocyanin (blue) and phycoerythrin (red), as accessory pigments in addition to chlorophyll a.

These pigments help cyanobacteria absorb light across a wider range of wavelengths than chlorophyll a alone, enhancing their photosynthetic efficiency.