Explanation

Pheretima posthuma is the common species of earthworm found in South Asia.

It belongs to the phylum Annelida.

It is important for soil fertility.

Explanation

During swimming, knees and ankles play a key role in kicking movements.

These joints allow flexion and extension, providing thrust in the water.

Explanation

Heart muscle (cardiac muscle) contracts automatically without conscious control — it's involuntary.

Neck and leg muscles are voluntary and controlled by conscious effort.

Explanation

Tulips, lilies, daffodils, and onions reproduce through bulbs, which are underground storage organs.

Bulbs store food and help the plant survive unfavorable conditions.

Explanation

Strawberries reproduce asexually through runners, which are horizontal stems that grow along the ground and produce new plants.

Cactus plants usually reproduce through cuttings.

Explanation

The Widal test is used to diagnose Typhoid fever.

It detects antibodies against Salmonella typhi and Salmonella paratyphi, the bacteria responsible for typhoid.

It is a serological test that checks for agglutination (clumping) of bacteria in response to specific antigens.

Explanation

Plasmodium is a protozoan parasite that causes malaria in humans.

It belongs to the phylum Apicomplexa, which includes other parasitic protozoa.

Explanation

Explanation

Muscular endurance is the ability of muscles to perform repeated actions over a long period without fatigue.

It is essential for activities like running, swimming, and cycling.

Explanation

The time period (T) of a simple pendulum is given by:

T ∝ √L

If the length (L) is made four times:

New time period T' ∝ √(4L)

T' ∝ 2√L

T' = 2T

The time period will become double.