Science psychology, homeostasis and stuff Flashcards
What are positive and negative feedback mechanisms?
Ways in which the brain regulates processes within the body
They maintain balance and homeostasis but operate in opposite ways.
What is the function of positive feedback?
Amplifies or strengthens a process or output
It reinforces the direction of a change, making the response larger or more intense.
Give an example of positive feedback.
Childbirth and blood clotting
In childbirth, there are increased uterine contractions during labor.
Describe the process of blood clotting as an example of positive feedback.
A chemical is released from torn tissue, activating platelets, which release chemicals to activate more platelets until the wound is clotted
This process continues until the wound is effectively closed.
What is the function of negative feedback?
Works to counteract or oppose a change, maintaining balance or homeostasis
It inhibits or reduces the initial change to prevent excessive responses.
Provide an example of negative feedback.
Regulating blood glucose levels after eating too much
This helps to bring blood sugar levels back to normal.
What role does the hypothalamus play in thermoregulation?
Triggers mechanisms to cool the body when too hot and raise temperature when too cold
Mechanisms include sweating and vasodilation for heat, shivering and vasoconstriction for cold.
Fill in the blank: Positive feedback _______ the direction of a change.
[reinforces]
True or False: Negative feedback mechanisms increase the intensity of a response.
[False]
List two mechanisms triggered by the hypothalamus when the body gets too hot.
- Sweating
- Vasodilation
List two mechanisms triggered by the hypothalamus when the body gets too cold.
- Shivering
- Vasoconstriction
What are the basic receptors in humans?
Phenoreceptors, photoreceptors, olfactory receptors, thermoreceptors, gustatory receptors
These receptors correspond to the five basic senses: hearing, sight, smell, touch, and taste.
What is the function of phenoreceptors?
Sense of hearing
Phenoreceptors, also known as auditory receptors, are located in the inner ears.
What is the stimulus for photoreceptors?
Light
Photoreceptors are responsible for the sense of sight.
What do olfactory receptors sense?
Chemicals
Olfactory receptors are located in the nose and are responsible for the sense of smell.
What is the primary function of thermoreceptors?
Sense of touch, pain, heat
Thermoreceptors are found in the skin and respond to temperature changes.
What do gustatory receptors detect?
Flavours
Gustatory receptors are located in the taste buds on the tongue.
What are the five key types of tastes?
- Sweetness
- Saltiness
- Sourness
- Bitterness
- Umami (savouriness)
These types of tastes are detected by gustatory receptors in the taste buds.
What is the stimulus for gustatory receptors?
Flavours
The receptors responsible for taste are called chemoreceptors.
What is the stimulus that touch receptors respond to?
Heat, cold, pressure, pain
Touch is sensed through various receptors in the skin.
What is the bottom layer of the skin called?
Dermis
The dermis contains nerve endings that detect touch.
How many receptors are estimated to be in the skin on our fingertips?
About 100 receptors
The fingertips have a high concentration of receptors for sensitive touch.
Which receptors are responsible for the sense of balance?
Phenoreceptors (auditory receptors)
These receptors also play a role in detecting sound.
