Lesson 13

What is blood made of?

In first-aid, you learn how to help people who are hurt. An important first-aid rule is:

Treat serious bleeding first.

A person can die very quickly from a loss of blood.

Blood is the main tissue of transport in your body.

It carries needed materials to the cells.

It carries waste materials away from the cells.

It has a liquid part and a solid part.

Plasma is the liquid part of blood.

-It is 90% water, and is straw colored.

-Digested food, important chemicals, and waste products are dissolved in plasma.

Blood Cells are solid matter carried in the blood. There are three kinds of blood cells.

Red Blood Cells:

-contains hemoglobin, which gives blood its red color

-hemoglobin carries oxygen to the cells

-hemoglobin picks up most of the carbon dioxide from the cells and takes it to the lungs.

White Blood Cells:

-fight disease and infection

-destroy harmful germs in the body

Platelets

-tiny, colorless pieces of cells

-help stop bleeding

-give off a chemical that helps blood clot

Blood has been called “The River of Life” because:

-it carries to the cells materials that are needed by the cells

-it carries away from the cells waste materials made by the cells

Place the items below where they belong in the chart.

Brought to cells Taken away from cells

oxygen Carbon dioxide

Dissolved foodExtra water

Extra salt

Excess heatvitamins