Lesson 20 - 6th Grade

The __________ system lets the body transport materials from one place in the body to another.

• digestive

• respiratory

• nervous

• circulatory

Blood carries messenger chemicals, or ______________, to body cells.

• hormones

• germ-fighters

• oxygen

• food

Each of the ______________ chambers in the heart plays a part in the circulation of blood through the body.

• two

• four

• six

• eight

The heart pumps oxygen-poor blood back to the ______________, where it becomes rich again with oxygen.

• tissues

• organs

• lungs

• body cells

___________________ carry oxygen-rich blood away from the heart.

• Veins

• Arteries

• Lungs

• Capillaries

The force of the blood pushing against the walls of the blood vessels is the ________________________ .

• blood pressure

• capillaries

• platelets

• red blood cells

• veins

Blood vessels that carry oxygen-poor blood to the heart

is the ________________________ .

• blood pressure

• capillaries

• platelets

• red blood cells

• veins

Very tiny branches of arteries and veins is the ________________________ .

• blood pressure

• capillaries

• platelets

• red blood cells

• veins

Parts of cells that help clot blood is the ________________________ .

• blood pressure

• capillaries

• platelets

• red blood cells

• veins

Cells that carry oxygen to other cells is the ________________________ .

• blood pressure

• capillaries

• platelets

• red blood cells

• veins