Concept 2 Flashcards
What is homeostasis?
The need of an organism to stay stable by regulating internal conditions, creates dynamic equilibrium.
Why do organisms take in stimuli?
They take them in and respond to them in order to maintain homeostasis.
What is stimulus?
A change in environment
What is the response to stimulus?
A change in the organism
What do feedback mechanisms do?
They evolve to help maintain homeostasis in organisms as they respond to stimuli. They also use the output of a system to signal a change in input psi that a system response can be stabilized or amplified.
Can feedback mechanisms be positive or negative?
Yes
What happens in a positive feedback loop?
The output (or product) of a system intensifies the response
What are examples of positive feedback mechanisms?
Human childbirth and Fruit ripening.
What happens in a negative feedback loop?
The output (or product) of a system causes a counter response to return to a set point (Trying to stabilize)
What are examples of Negative feedback loops?
Human body temperature, water concentration, and blood sugar regulation
What does the cell membrane do to help maintain Homeostasis?
It controls movement of things coming from in and out of the cell.
What can pass through the cell membrane?
Small non-polar molecules, hydrophobic molecules, and water.
What can’t pass through the cell membrane?
Polar and large molecules.
What is the kind of transport that goes in and out of the cell membrane classified as?
Passive or Active
Does passive transport require extra energy?
No
