Explanation

• The longest cell in the human body is the nerve cell (neuron).
• Some neurons can extend up to 1 meter in length.
• They transmit impulses throughout the body.

Additional information:

• The smallest cell in the human body is the sperm cell (spermatozoon).
• It is measures approximately 4–5 micrometers (µm) in length.
• It is mainly consisting of a nucleus and a tail.

Last verified on 23-04-2026

Explanation

• Allergy is an abnormal immune response to harmless substances like dust or pollen.
• It occurs when the body reacts excessively to an allergen.
• This reaction involves the immune system producing antibodies.
• Thus, allergy is mainly due to an antigen–antibody reaction.

Last verified on 23-04-2026

Explanation

• A reflex action is a quick, automatic response to a stimulus.
• It is mainly controlled by the spinal cord, which is part of the central nervous system.
• This allows fast response without involving the brain immediately.
• Thus, reflexes are coordinated by the central nervous system.

Last verified on 23-04-2026

Explanation

• The kidney is an important organ responsible for filtering blood and forming urine.
• Its structural and functional unit is the nephron.
• Each kidney contains millions of nephrons.
• They perform filtration, reabsorption, and secretion.

Last verified on 23-04-2026

Explanation

• Oxytocin is the primary hormone responsible for causing the labor pain
• It is often referred to as the "love hormone" or "cuddle chemical,"

Last updated by NA on 22-April-2026