3 Homeostasis and control Flashcards
What are the things regulated by homeostasis?
Temp
blood glucose
pH
Blood pressure
What happens during a haemorrhage?
fall in blood pressure –> change detected by baroreceptors –> send a message down the glossopharangeal nerve to the medulla oblongata (pressure and breathing) –> signal sent down the autonomic symapathetic nervous system to the het and blood vessels –> blood pressure increases
What happens in a negative feedback loop?
- change in variable
- sensor
- afferent pathways
- intergrating centre (CNS/endocrine gland…)
- efferent pathways
- effector
What happens in a exhaustion?
-lots of sweat
-less blood volume (dehydration)
-blood diverted to skin
-less blood flow to major organs
-less pressure
lessblood to brain
-dizziness–>unconciousness
What happens in a heat stroke?
- despite bodies efforts temp keeps rising
- effects temp regulatory area of the brain
- failure of this area
- no sweat production
- temp continues to climb
GIve three examples of positive feedback
- lactation
- blood clotting
- labour
What id the positive feedback bit of blood clotting?
activation of clotting factors –> activation of thrombin —> activates more clotting factors
Which muscle types are stimulated by the somatic nervous system?
skeletal
Which muscle types are stimulated by the autonomic nervous system?
Smooth and cardiac and glands
Which types of nerves system stems mainly from the middle of the spine?
sympathetic
Which types of nerves system stems mainly from the top and bottom of the spine?
Autonomic
What are the middle regions of the spine called?
thoracic and lumbar
What are the two types of hormone?
thyroid -for metabolism
and growth
which nervous system has short pre ganglionic fibres?
sympathetic
which nervous system has long pre ganglionic fibres?
parasympathetic
