Homeostasis Flashcards
(24 cards)
What is the definition of homeostasis?
An organism is said to be at homeostasis when its internal environment contains the optimum amount of chemicals, has optimal temperature, and has optimal pressure for the survival of living cells.
What does the term ‘homeostasis’ derive from?
Homeo = same; Stasis = standing still.
What is the physiological response to changes inside and outside the body?
Resistance to change, ensuring that our body functions within a normal range.
What are the two types of regulation that maintain homeostasis?
- Intrinsic/autoregulation
- Extrinsic regulation
What is intrinsic/autoregulation in homeostasis?
Automatic response within a cell, tissue, or organ to some environmental change.
What controls extrinsic regulation?
Responses controlled by the nervous and endocrine systems.
What are the three components required for homeostasis?
- Receptor
- Control Centre
- Effector
What is the role of a receptor in homeostasis?
Sensor that monitors the physiological environment and signals a change.
What does the control centre do in the homeostasis process?
Processes the signal and sends instructions for a response to occur.
What is the function of the effector in maintaining homeostasis?
Carries out instructions sent by the control centre.
What is a negative feedback loop?
The response of the effector reduces or stops the stimulus, bringing the body back into homeostasis.
What is a positive feedback loop?
The response of the effector increases the change of the stimulus, moving the body away from homeostasis.
What are some primary organ systems involved in homeostasis?
- Integumentary system
- Muscular System
- Cardiovascular system
- Nervous System
Fill in the blank: The regulation of blood sugar involves insulin from the pancreas and _______ from the pancreas.
glucagon
What happens to blood glucose levels when they are too high?
Insulin is released, and excess glucose is stored as glycogen.
What happens to blood glucose levels when they are too low?
Glucagon is released, and the liver breaks down glycogen to release glucose into the blood.
What do baroreceptors monitor in the regulation of blood pressure?
The degree of stretch in blood vessels as blood flows through them.
True or False: Positive feedback loops are used to move the body towards homeostasis.
False
What physiological process is enhanced during childbirth?
Release of oxytocin during contractions.
What is the role of sodium (Na+) ions in the nervous system?
They move from a graded potential to an action potential.
What branch of science is physiology concerned with?
Function of organisms.
Physiological systems integrate with each other to ensure what?
Our body works within the normal range.
Describe one example of negative feedback in the human body.
Regulation of blood sugar levels.
Describe one example of positive feedback in the human body.
Release of oxytocin during childbirth.
