Explanation

Calcium is a mineral that is necessary for life.

Explanation

The central nervous system consists of the brain and spinal cord. 

Explanation

 Hepatic portal vein

The portal  or hepatic portal vein is the blood vessel that carries blood from the gastrointestinal tract, gallbladder, pancreas, and spleen to the liver.

Explanation

DNA replication is the process by which DNA makes a copy of itself during cell division

Explanation

The right ventricle pumps the blood to the lungs where it becomes oxygenated. 

The heart is a pump, usually beating about 60 to 100 times per minute.

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Explanation

 II only

Explanation

• Skin is the largest organ of our body.
• The skin is made up of three main layers: the epidermis, dermis and subcutis.
• It covering approximately 22 square feet (2 square meters) in adults.

Explanation

The hinge joints allow movement in one plane only,

That is up and down or backward and forward.

The fingers, toes, elbows, knees, and ankles contain hinge joints.

Explanation

For the protection of ears, Muffs should be used.

They are designed specifically to protect the ears from loud noises 

It can help prevent hearing damage

Explanation

There are 4 main blood groups (types of blood) – A, B, AB and O.

Your blood group is determined by the genes you inherit from your parents.