tuesday, sept 20

Tuesday, Sept 20

Objective: I will analyze feedback loops

BR: Explain what homeostasis is and provide an example.

**This is a short week – our quiz will be on THURSDAY**

Tuesday, Sept 20

Objective: I will analyze feedback loops

BR: Explain what homeostasis is and provide an example.

**This is a short week – our quiz will be on THURSDAY**

4 MINUTES REMAINING…

Tuesday, Sept 20

Objective: I will analyze feedback loops

BR: Explain what homeostasis is and provide an example.

**This is a short week – our quiz will be on THURSDAY**

3 MINUTES REMAINING…

Tuesday, Sept 20

Objective: I will analyze feedback loops

BR: Explain what homeostasis is and provide an example.

**This is a short week – our quiz will be on THURSDAY**

2 MINUTES REMAINING…

Tuesday, Sept 21Last chance to view bell ringer – 1 min

Objective: I will analyze feedback loops

BR: Explain what homeostasis is and provide an example.

**This is a short week – our quiz will be on THURSDAY**

30 Seconds Remaining…

10 Seconds Remaining…

Time’s up! Put Bell

Ringer in Folder

Today’s Agenda:

• Feedback loop Notes• HW

Homeostasis

• The body’s ability to maintain relatively stable internal conditions even though the outside world is continuously changing

Some examples of homeostasis

• Sweating when hot• Shivering when cold• Stomach growling if hungry• Yawning if tired• Breathing heavy if exercising

Obj: Analyze Feedback LoopsFeedback loops regulate homeostasis. There are two types – positive and negative. Write the notes in the following T-chart:

• Homeostasis will be opposite the stimulus

• Most

homeostasis

examples

• Homeostasis will be same as the stimulus

• Ex: Childbirth & labor contractions

Components of a Negative feedback loop:

• _______________________ – causes a change in the variable

• _______________________ – detects the change and tells control center

• _______________________– determines set point and tells effector when to respond

• _______________________ – causes a change that will stop the stimulus

• _______________________– variable is now the opposite of the stimulus

STIMULUS

RECEPTOR

HOMEOSTASIS

CONTROL CENTER

EFFECTOR

A FEEDBACK LOOP WILL

ALWAYS GO IN THAT ORDER!

How can you check that this is a negative feedback loop?

• The stimulus and homeostasis will always be the opposite!

Homeostasis & Feedback loop video

http://health.howstuffworks.com/human-body/systems/endocrine/adam-200092.htm

Label the components on the feedback loops: The components are stimulus, receptor, control center, effector and homeostasis.

STIMULUS

RECEPTOR

HOMEOSTASIS

CONTROL CENTER

EFFECTOR

STIMULUS

RECEPTOR

HOMEOSTASIS

CONTROL CENTER

EFFECTOR

What would be the control center in this feedback loop?

____________________________

Stomach

__________________________

Person consumes food

____________________________

Stomach has no food to digest

_______________________________

Hunger/stomach growls

____________________________

Brain

What would be the effector in this feedback loop?

____________________________

Stomach

__________________________

Person consumes food

____________________________

Stomach has no food to digest

_______________________________

Hunger/stomach growls

____________________________

Brain

How do you know this is a negative feedback loop?

____________________________

Stomach

__________________________

Person consumes food

____________________________

Stomach has no food to digest

_______________________________

Hunger/stomach growls

____________________________

Brain

They are opposite!