Chapter 1 Flashcards
Why do we need homeostasis in our body?
to maintain balance in the body.
What allows for homeostasis to function?
Positive and Negative feedback
Define Negative feedback
if something goes up, negative feedback acts to bring it back down to its original value. For example, if your temperature goes up NF will act by dilating blood vessels and cause more oxygen to flow and cause you to sweat to cool you down.
Define Positive feedback
If something goes up, it will continue to go up away from its original value. For example, blood clotting.
What is being used to maintain homeostasis?
Gene regulation + energy + chemical reactions.
What is the order of responding to a stimulus?
Receptor -> Afferent signal -> control center (interneuron) -> brain -> effector signal -> effector
Where is amplification present in?
Positive feedback- another way to distinguish PF from NF.
Explain PF for blood clotting.
Damaged cells in the blood vessel wall release chemicals that begin the clotting process. Chain reactions occur due to the chemicals, platelets, that amplify and form a clot. More and more platelets will be attracted and accelerate the process.
What happens if homeostasis is not maintained?
Disease.
What defines each level or organization?
You go from micro to macro; less specific to more specific. Ex. Cardiac muscle tissue -> epithelial +connective tissue -> heart -> cardiovascular system.
What would happen to bladders if they weren’t made up of transitional epithelial tissue?
One of the great properties of that tissue is that it can allow for expansion. Without this, bladders wouldn’t be able to pack a lot urine and hence not be able to carry out their function.
Define autoregulation.
If there is a problem present within the organ, it will fix it. Ex. Kidneys are getting enough O2, will start to dilate to get more blood flow.
Define extrinsic regulation
Endocrine system will send hormones and such to fix the issue. For example, smelling popcorn will active sensory receptors for these systems to respond to.
