Rocket reads a heart book. It says, "Lub-dub!"
Raven asks, "What do you notice about that sound?"
Nova says, "Listen for doors closing."
Your heart has little doors inside.
They are called valves.
A valve opens to let blood go forward.
Then it shuts so blood cannot go backward.
The doors shutting make the heart sound.
Doctors call it lub-dub.
A doctor listens with a tool called a stethoscope.
It helps the doctor hear the lub-dub.
Each lub-dub is one heartbeat.
| Sentence | True or false? |
|---|---|
| Valves keep blood going forward. | ? |
| Valves let blood go backward. | ? |
| Each lub-dub is one heartbeat. | ? |
| A healthy heart says lub-dub. | ? |
Here are new sight words.
Look at each word. Say it. Spell it.
Move: M-O-V-E.
Try: T-R-Y.
Lub-dub! You listened like a scientist.
Tomorrow you will feel your own heartbeat.