Feedback Mechanisms Coloring Sheet

Cellular Control Systems — Year 12 Science

Name:

Date:

🎨 Part 1: Color the Feedback Loop Diagrams

Instructions: Read each diagram description below. Use the color key to shade each box in the feedback loop. Then answer the question that follows each diagram.

🖍 Color Key:

BLUE = Stimulus RED = Response GREEN = Control Center ORANGE = Effector YELLOW = Receptor

Diagram A: Negative Feedback Loop (Body Temperature)

Color each box below using the color key. The arrows show the direction of the feedback signal.

Label guide for your drawing: Draw and color boxes connected by arrows in this order:

[BLUE] Stimulus: Body temp rises above 98.6°F → [YELLOW] Receptor: Thermoreceptors in skin/brain → [GREEN] Control Center: Hypothalamus → [ORANGE] Effector: Sweat glands activate → [RED] Response: Body temp drops back to normal

↩ (Arrow returns from Response back to Stimulus — this is the negative feedback!)

1. In negative feedback, does the response increase or decrease the original stimulus? Circle your answer:

Increases it — pushes the change further

Decreases it — reverses the change back to normal

Diagram B: Positive Feedback Loop (Childbirth)

Color each box using the same color key. Notice how this loop works differently!

Label guide for your drawing:

[BLUE] Stimulus: Baby's head presses on cervix → [YELLOW] Receptor: Stretch receptors in cervix → [GREEN] Control Center: Hypothalamus/Pituitary gland → [ORANGE] Effector: More oxytocin released → [RED] Response: Stronger uterine contractions

↩ (Arrow returns — Response amplifies the original stimulus!)

2. In positive feedback, the response amplifies the original stimulus. Why must positive feedback loops eventually stop?

📝 Part 2: Key Terms & Short Answer

3. Match each key term to its correct definition by writing the correct letter on the line:

A. Homeostasis

B. Negative Feedback

C. Positive Feedback

D. Effector

E. Control Center

___ The organ/muscle that carries out the corrective response

___ A loop that amplifies the original change

___ The body's ability to maintain a stable internal environment

___ Processes and sends instructions (e.g., the hypothalamus)

___ A loop that reverses the original change

4. Which type of feedback mechanism — negative or positive — is more common in the human body for maintaining homeostasis? Explain why.

5. Blood glucose regulation is a classic example of a feedback mechanism. Check ALL steps that are part of this negative feedback loop:

Blood glucose rises after eating a meal

The pancreas releases insulin

Cells absorb glucose, lowering blood sugar levels

The heart beats faster to pump more glucose

Blood glucose returns to the normal range (~70–100 mg/dL)

6. The hypothalamus is sometimes called the body's "thermostat." Using what you know about feedback mechanisms, explain what this comparison means in your own words.

7. 🌟 Bonus — Color & Label: In the box below, draw your own simple feedback loop for blood pressure regulation. Use the color key from Part 1. Include: Stimulus → Receptor → Control Center → Effector → Response → (feedback arrow).