Unit 1: Homeostasis Flashcards
Define homeostasis
the maintenance of the constant conditions in the internal environment of an organism
What conditions does the body control by homeostasis?
- body temperature
- osmotic pressure
- waste levels
What does homeostasis mean?
Same state
Which 6 tasks must the body be able to complete to function properly?
- regulate respiratory gases
- maintain water and salt balance
- regulate energy and nutrient supply
- maintain constant body temperature
- protect against pathogens
- make repairs when injured
What is a set point?
a narrow range in which the body functions properly
State the set point for:
- body temperature
- blood pH
- blood glucose
- blood pressure
- heart rate
- body temperature: 36.5 - 35.7
- blood pH: 7.35 - 7.4
- blood glucose: 100mg/mL
- blood pressure:120/80 mm Hg
- heart rate: 60 bpm
What is a receptor?
a nerve that detects deviations from the set point and signals to the control center along a sensory neuron
What is an effector?
a muscle or gland that receives a signal from the control center and causes a change in the body to restore the normal set point
What is the control center?
The organ that interprets the signal from the sensory neuron and signals to the effector along a motor neuron to cause a change
What is hypothermia?
- below/low temperature
- when you’re too cold
Differentiate between vasodilation and vasoconstriction.
Vasodilation occurs when the superficial arteries increase in diameter when the body is too hot or experiencing hyperthermia while vasoconstriction occurs when the body is too cold and the superficial arteries reduce in diameter.
Which muscles contract and relax causing us to shiver when we are cold and move blood to our cores?
the skeletal muscles.
What and where is the control center for body temperature and water level regulation?
the hypothalamus and it is found in the brain
Blood vessels go through all your tissues which means they _______
innervate
Why is homeostasis important?
Because our cells and enzymes function at optimum conditions. If our body is out of those optimum conditions for too long we could die.
What is ADH?
- antidiuretic hormone
- a hormone released by the pituitary gland that increases reabsorption of water in the kidneys
What is thermoregulation?
the maintenance of constant body temperature at a set point of 36.5 - 37.5
What is osmoregulation?
the maintenance of a constant water level in the body’s internal environment
What is waste management?
removing waste products of digestion from the blood
What are chemoreceptors? Name 2 of them and where they are found.
- chemical receptors
- carotid bodies found in the carotid arteries in the neck
- aortic bodies found in the aorta in the heart
Why are chemoreceptors found in the aorta and carotid arteries?
The aorta gets almost all of the body’s blood in 1 min so any blood that has a pH out of the set point can be easily detected and the carotid arteries go to the brain so, any blood past its blood pH set point needs to be detected before it gets there
What are osmoreceptors and where are they found?
- water receptors
- found in the hypothalamus