Explanation

A scalar quantity only has magnitude (a numerical value) and no direction.

Speed is the magnitude of velocity,

Which means it tells you how fast something is moving without considering its direction. 

a) Velocity:

Velocity is a vector quantity because it has both magnitude (speed) and direction. 

b) Acceleration:

Acceleration is also a vector quantity as it describes the rate of change of velocity,

which means it needs both magnitude and direction to be fully defined. 

d) Force:

Force is a vector quantity as it has both magnitude (how strong the push or pull is) and direction. 

Explanation

Explanation

Leech is a segmented worm, placed in phylum Annelida, class Hirudinea.

Its body is soft, elongated, and segmented, a key feature of annelids.

Explanation

Rabies disease is caused by Virus.

Rabies means پاگل جانور یا پاگل کتے کے کاٹنے سے ہونے والی بیماری

Rabies is caused by the Rabies virus, which belongs to the Rhabdoviridae family.

It affects the central nervous system, leading to inflammation of the brain.

It is usually transmitted through animal bites.

Explanation

Explanation

The term “enzyme” was first used in 1878 by Wilhelm Kühne, a German physiologist.

He used it to describe biological catalysts distinct from living cells, derived from the Greek word meaning “in yeast.”

Explanation

Trypanosoma enters the human body through the bite of the tsetse fly and infects the blood and nervous system.

The disease is called African sleeping sickness, marked by fever, fatigue, and disturbed sleep cycles.

Explanation

Proteins are the most abundant organic substances in living bodies, essential for structure and function.

Water is most abundant overall, but it is inorganic, so the correct organic substance is protein.

Explanation

The percentage of nitrogen by weight in the human body is approximately 3.3%.

Nitrogen is one of the four main elements that make up about 96% of the human body, alongside oxygen (65%), carbon (18.5%), and hydrogen (9.5%).

It is a crucial component of important molecules such as proteins, DNA, and enzymes. 

Explanation

Protoplasm is called the living material of the cell.

It consisting of cytoplasm and nucleus.

While amino acids and other biochemicals are present, the main term describing living cell material is protoplasm.