Choose the correct option.

1. The group of organs working together to perform a particular function is called
   1. A cell system
   2. A tissue system
   3. An organ system
   4. None of these
2. The circulatory system helps in transportation of
   1. Oxygen
   2. Nutrients
   3. Water
   4. All of these
3. This is not a blood vessel.
   1. Atria
   2. Capillaries
   3. Arteries
   4. Veins
4. To keep the heart healthy and strong, we should
   1. Eat a balanced diet
   2. Exercise
   3. Practice yoga
   4. All of these
5. The largest artery is
   1. Superior vena cava
   2. Aorta
   3. Arterioles
   4. None of these

Choose the correct option to fill in the blank.

1. The heart is a ___________ (muscular/non muscular) organ that pumps blood to all parts of the body.
2. The lower chambers of the heart are called ___________ (ventricles/auricles).
3. We should walk for at least half ____________ (a minute/an hour) to keep our healthy.
4. The _____________ (RBCs/WBCs) protect the body from infectious diseases.
5. The ______________ (veins/capillaries) are the thinnest blood vessels.

Name the following.

1. The pumping organ that pumps blood to all parts of the body.
2. The rhythmic movement that the heart makes while pumping the blood.
3. The upper chambers of the heart.
4. The names of two yoga exercises.

What is an organ system? Give an example.

Define heart. Also, give its location in the body.