Homeostasis Flashcards
(17 cards)
What is homeostasis?
the maintenance of a stable internal environment while adjusting to changing external conditions.
What are some internal environments?
Core body temp.
Arterial Oxygen content.
Arterial carbon dioxide content.
Blood pH.
Blood glucose.
Blood pressure.
Blood volume.
Blood osmolality.
What are some external environment?
External temp.
Hypoxic exercise.
Exercise.
Feeding.
Fasting.
Hydration status.
Why is homeostasis important?
Homeostasis ensures that regulated variable in the internal environment are maintained within a range of values that are compatible with life.
What body systems are involved in homeostasis?
All body systems are involved in homeostasis.
What is negative feedback regulation? And, who came up with it?
Planned corrective behaviour of any system which brings it back to baseline whenever it moves away from baseline. (St Clair Gibson, 2015)
What is feedforward regulation?
Mechanisms which cause changes in the controlled variables (e.g. ventilation, cardiac output, hepatic glucose release) in anticipation of imminent demands (e.g. exercise)
What does a change in ‘set-point’ of negative feedback mean? Explain.
A change in set point of negative feedback allows organisms to adapt to ever-changing external conditions. During exercise the set point for mean arterial blood pressure is adjusted to higher levels, this allows cardiac output to increase as much as possible therefore providing a substantial oxygen supply to the muscles. If this did not happen the increase in cardiac output would be limited meaning that the blood and oxygen supply to the muscles would be impaired.
What are the two communication systems in the body?
Nervous System and Endocrine System.
What is the nervous system?
A system made up of neurons in which signals are sent through to the central nervous system (afferent) and away from the central nervous system (efferent).
What is an afferent neuron?
A neuron which sends signals TO the central nervous system.
What is an efferent neuron?
A neuron that sends signals AWAY from the central nervous system.
What is the Endocrine System?
Secretes hormone from glands into the blood which travel to and have an effect on distant organs.
What are some of the glands in the Endocrine System?
Adrenal gland.
Thyroid.
Pancreas.
Pituitary Gland.
Brain.
Ovary.
Testicle.
Thymus.
What is a hormone?
A chemical messenger.
What if homeostasis is disturbed?
disturbed homeostasis can cause disease as it can mean there is a failure st the control centre level, an impaired ability of the effector to respond, and/or altered sensitivity of the sensors. E.g. Type 1 Diabetes in which there is an inability to produce insulin.
How does exercise pose a threat to homeostasis?
Exercise requires a coordinated responses from multiple bodily systems in order to maintain homeostasis.
