OD4.U12.RD

Choose the correct answer:

The gas formed when carbon is burned, or when people or animals breathe out

• blood

• carbon dioxide

• vein

• system

Choose the correct answer:

• stomach

• skin

• diaphragm

• trachea

Answer explanation

Choose the correct answer:

Capillaries are smaller than ________ and _____.

• carbon dioxide and veins

• arteries and pulse

• arteries and blood

• arteries and veins

There are two of them in our bodies. They help us breathe.

• heart

• lungs

• blood

• veins

The beating of your heart that you can feel in your wrist.

• pulse

• carbon dioxide

• body

• artery

Write the correct word:

and that circulatory system includes the heart, arteries, and ____.

(lungs/ trachea/ veins)

Write the correct word

Our bodies don't need _________. (oxygen/ carbon dioxide)

A cell is the ________ basic unit of a plant, an animal or a human.

• smallest

• biggest

The muscle between your lungs and your stomach that helps you to breathe

• capillary

• veins

• diaphragm

• heart

Fill in the blank:

______ is a group of things or parts that work together.

(gas/ carbon dioxide/ system)