P2 - 5.1 Homeostatis Flashcards
What is homeostasis
Maintaining a stable internal environment
What conditions do animal cells need to function correctly
- it cannot be too hot or too cold
- it cannot be too acidic or to alkaline
- good supply of glucose
- good supply of water
How does our body make sure our cells dont reach conditions where they wouldn’t function properly
Our bodies regulate everything to make sure everything is kept around the right levels
What 2 things does our body not regulate (only happens in small bounds)
Temperature
Glucose levels
- these often fluctuate but only in small bounds
What is the definition of homeostasis
Homeostasis is the regulation of conditions inside the body to maintain a stable internal environment, in response to both internal and external conditions
What kinds of external conditions can affect our internal conditions
- temperature being too hot
- temperature being too cold
What temperature should the human body be roughly
37°C
What is the name of the function our bodies do to change from optimal conditions to convert into a signal to reverse the change
Automatic control
What is automatic control in homeostasis
When there is a change from optimal conditions, a signal can be sent in order to reverse the change and change our levels back to normal
What are optimal conditions
Conditions that are outside of the conditions we are used to
What are the 3 systems in automatic control
- receptors
- coordination centres
- effectors
What is a receptor
Receptors detect a change such an an increase in temperature
What is the coordination centre
The coordination centre is made up of your brain and spinal chord, they interpret the change and then decide what needs to be done about it
What is an effector
An effector carries out a change such as releasing hormones or contracting muscles
What are the 2 main types of effectors
Glands
Muscles
In an automatic control system what might the effector, gland do
Release hormones
In an automatic control system what might the effector, muscle do
The muscle might contract
What 2 types of systems are linked to automatic control in homeostasis
Nervous system
Endocrine system
What is the nervous system
The nervous system is subconscious, very fast and precise. It sends electrical impulses through nerves to send information to respond to things very quickly to avoid the body getting harmed
What is the endocrine system
Hormones (that are small chemicals) that are released into the bloodstream. They can travel around the entire body but only will affect certain cells that have the correct receptors.
The endocrine system is much slower, longer lasting and more generalised in comparison to the nervous system
What are some similarities and differences of the nervous system and endocrine system
Similarities:
- both respond to things in the body for example homeostasis
Differences:
- NS is very fast whereas ES is very slow
- NS is via electrical impulses whereas ES is through bloodstream
- NS is precise whereas ES is more generalised
- NS is specific to certain body part etc brain, spinal chord whereas ES can travel around entire body
What is the name of the mechanism that triggers an automatic control in homeostasis
Negative feedback
What is negative feedback in homeostasis
Whenever a level of something gets too high ie. Glucose levels in blood, negative feedback decreases it again to return the levels to normal
What happens if the amount of glucose levels in our blood is to too low?
Negative feedback increases it to return it to normal
What happens if the amount of glucose levels in our blood is to too high?
Negative feedback decreases it back to normal
Scenario:
You have walked into a room that is very cold.
Explain how your body will respond to this.
Your receptors in your skin will detect the external conditions have a low temperature. The receptors carry this electrical impulse to sensory neurone to relay neurone in spinal chord which informs brain and then decides the response which this electrical impulse travels through motor neurone to effector such as muscle that will contract to make us shiver to heat our bodies back to the normal temperature
Scenario:
You have walked into a room that is very hot.
Explain how your body will respond to this.
Receptors in your skin detect the rise in temperature from external conditions and sends signal through sensory neurone to coordination centre the relay neurone then takes electrical impulse to motor neurone and the effector causes us to sweat to release heat and return body temperature back to normal
Why does the body need to maintain optimal conditions?
For optimal enzyme action and cell function
Which of these are considered ‘internal conditions’?
1) Room temperature
2) Blood glucose concentration
3) Blood pH
2) Blood glucose concentration
3) Blood pH
Which of these are considered ‘external conditions’?
1) Blood oxygen concentration
2) Room temperature
3) The amount of fluids your drink
2) Room temperature
3) The amount of fluids your drink
