Explanation

Since none of the given options show features like cell specialization or permanent cell association

The transition to multicellularity is better supported by colonial organization and cell differentiation.

Contractile vacuole is used for osmoregulation 

Encystment is a survival mechanism to withstand unfavorable conditions

Binary fission is a type of asexual reproduction

Explanation

Nitrous Oxide is significantly more potent at trapping heat than methane and carbon dioxide

N2O absorbs infrared radiation very strongly and stays long in the atmosphere.

It has a GWP of approximately 265–298, making it nearly 300 times more potent than CO₂ per unit

Explanation

The corpus callosum is only found in placental mammals.

It spans part of the longitudinal fissure, connecting the left and right cerebral hemispheres,

It consists of 300 million fibres 

Explanation

• Hard acids are small, highly charged, and less polarizable.

• Hard bases are also small, highly electronegative, and less polarizable.

• Therefore, hard–hard interactions are most stable.

Example:

• Hard acid: H⁺, Al³⁺

• Hard base: F⁻, OH⁻

Rule to remember:
Hard acid → Hard base
Soft acid → Soft base

Question updated on 21-feb-2026

Explanation

• Solubility product (Ksp) depends only on temperature.
• When temperature increases, the value of Ksp increases.
• As an equilibrium constant, its value is independent of concentration or the presence of other ions, changing only when the temperature changes, which alters the ion concentrations at saturation

Explanation

Humans have 22 pairs of autosomes and 1 pair of sex chromosomes.

Chromosome 21 is the smallest autosome in terms of base pairs.

Chromosome 1 is the largest autosome.

Chromosome 23 refers to sex chromosomes (X or Y), not autosomes.

Chromosome 21 is associated with Down syndrome when trisomic.

Last updated question 17-02-2026

Explanation

• Oxidation state indicates the number of electrons an atom has gained or lost.
• Moving from –3 → 0 means the element loses 3 electrons.
• Loss of electrons is called oxidation.
• This process increases the element’s oxidation number.
• Example: Nitrogen in NH₃ (–3) → N₂ (0) during oxidation.

Last updated question 17-02-2026

Explanation

• Cell membrane contains phospholipids, proteins, and glycoproteins.
• Glycoproteins form a sticky outer layer (glycocalyx).
• This layer slows the movement of molecules across the membrane.
• Glycolipids also reduce diffusion slightly, but less than glycoproteins.
• Glycerol does not affect cell diffusibility significantly.

Last updated question 17-02-2026

Explanation

Explanation