Unit 0: Homeostasis, Levels of Org, Body Systems

Maintaining body temperature is an example of a:

• negative feedback loop
• positive feedback loop

Rapid growth during puberty causes your body to release more and more growth hormones. As you grow, more and more growth hormones are released until puberty is reached, and then the hormones stop.

• Positive Feedback Response
• Negative Feedback Loop 

If the calcium in your blood decreases below homeostasis levels, a gland in the brain will sense the decrease and send a chemical message to your bones. Your bones will release calcium into the blood, bringing blood calcium levels back up.

• Positive Feedback Response
• Negative Feedback Loop 

When glucose levels in the blood rise, your brain sends a signal to your pancreas. The pancreas releases insulin, which opens channels in cell membranes to allow glucose to enter the cell, lowering blood sugar levels. 

• Positive Feedback Response
• Negative Feedback Loop 

When you get cut, your skin cells release hormones that signal platelets to come and stop the bleeding. Platelets then release more hormones that signal even more platelets to help stop bleeding. The hormone signals continue until the cut is closed.

• Positive Feedback Response
• Negative Feedback Loop 

Which system sends electrical messages that helps control the body's responses to internal and external changes?

• nervous
• endocrine
• reproductive
• integumentary

These two body systems regulate feedback mechanisms.

• Skeletal & Muscular
• Skeletal & Endocrine
• Muscular & Nervous
• Endocrine & Nervous

Which of the following responds to the output message from the Control Center?

• Effector

• Receptor

• Sense Organs

• Brain & Spinal Cord

This receives information from Receptors, coordinates a response, & sends it to the Effectors.

• Control Center

• Sense Organs

• Muscles & Glands

• Hormones

Which parts of the body are usually Effectors?

• Sense Organs

• Muscles & Glands

• Control Center

• Arms & Legs