Feedback Loops

Feedback Loops

Feedback loops are biological mechanisms whereby homeostasis is maintained. This occurs when the product or output of an event or reaction changes the organism's response to that reaction.

Negative Feedback Loops

• causes a decrease in function

• the feedback tends to stabilize the system

• occurs in response to some kind of stimulus

• can be referred to as homeostasis, as in biology

Example of Negative Feedback

Control of blood sugar (glucose) by insulin is a good example of a negative feedback mechanism. When blood sugar rises, receptors in the body sense a change. In turn, the control center (pancreas) secretes insulin into the blood effectively lowering blood sugar levels.

Positive Feedback

• occurs in nature when the product of a reaction leads to an increase in that reaction

• in homeostasis, a positive feedback loop moves a system further away from the target of equilibrium

• Example, ripening of fruit or childbirth

Multiple Choice

What is an example of Negative Feedback?

• Childbirth

• Fruit Ripening

• Blood Glucose Regulation

Multiple Choice

What is an example of Positive Feedback?

• Temperature Regulation

• Blood Glucose Regulation

• Fruit Ripening

Multiple Choice

What type of feedback loop is represented here?

• Positive

• Negative

Multiple Choice

What type of feedback loop is represented here.

• positive

• negative

Multiple Choice

What type of feedback loop is represented here?

• Positive

• Negative

Multiple Choice

What type of feedback loop is represented here?

• Positive

• Negative

Multiple Choice

What type of feedback loop is this?

• Positive

• Negative

Multiple Select

Check all the statements representing negative feedback loops

• regulatory

• return body to set point

• accelerates action

• leads to disease

Multiple Choice

The "effect" of a given stimulus is the...

• response
• stimulus
• cause
• result

Multiple Choice

The "cause" for something to happen is the

• response
• effect
• stimulus
• homeostasis

Multiple Choice

Humans have ___ for body temperature, blood glucose concentrations, electrolyte concentrations, pH levels, tendon tension and variables.

• positive feedback mechanisms
• set points
• a wide internal range
• no regulation

Multiple Choice

Failure to maintain homeostasis could result in:

• lack of internal balance
• eventual death
• difficulty carrying on metabolism 
• all three