How Your Eyes See

What You'll Learn

Reflexes are automatic responses that happen without conscious thought. When you touch something hot, your hand pulls away before your brain even registers the pain.

Key Words

organ system
tissue
cell

Steps

Step 1 — Read

Read and learn: Reflexes are automatic responses that happen without conscious thought. When you touch something hot, your hand pulls away before your brain even registers the pain.

Step 2 — Do

Follow the procedure carefully, step by step.

Step 3 — Observe

Watch carefully for any changes and note the time.

Step 4 — Record

Create a data table to organize your measurements.

Check Your Understanding

Question 1

1 of 3

What is the largest organ of the human body?