Bill Nye - The HEart

The heart is a __________ the size of your fist.

• muscle

• bone

• organ

• tissue

The heart's job is to pump __________ throughout the body.

• air

• blood

• water

• lymph

There are four __________ in the heart.

• chambers

• valves

• muscles

• arteries

At rest, a heart beats 60 to 100 beats per __________.

• second

• minute

• hour

• day

Electricity makes muscles __________.

• relax

• contract

• grow

• shrink

The Sinoatrial __________ gives the heart the charge to pump.

• node

• valve

• chamber

• artery

Skeletal muscles __________ movement from your bones.

• prevent

• allow

• restrict

• slow

The heart muscle is called the __________ muscle.

• cardiac

• skeletal

• smooth

• voluntary

Exercising will __________ the heart muscle.

• weaken

• strengthen

• damage

• ignore

The heart pumps __________ during exercise.

• faster

• slower

• the same

• irregularly