Homeostasis and the nervous system Flashcards
what is the role of a receptor
to detect a stimulus
why does the body need to maintain optimal conditions
for optimal enzyme action and cell function
what’s the difference between internal conditions and external conditions
internal- refers to conditions inside the body e.g body temp
external- refers to conditions outside the body e.g room temp
what is the role of a coordination centre
receives and processes the information from receptors then organises a response
what is the role of an effector
detect stimuli (changes in the environment)
what is a homeostasis
the regulation of conditions inside the body to maintain a stable and internal environment,
- in response to changes in both internal and external conditions
name the homeostatic control mechanisms
-receptors
-coordination
-effectors
what are the 2types of effectors and what do they do when stimulated
muscles- contract
glands- release hormones
what is negative feedback
a mechanism that restores a level back to optimum in a system
what are the key differences between the nervous system and the endocrine system
endocrine-
Name 2 internal conditions
-blood glucose concentration
-blood pH
Name 2 external conditions
-room temp
-amount of fluid you drink
Homeostasis relies on automatic control systems.
In what order are signals passed along the control system?
receptor➔ coordination centre ➔ effector
where are the coordination centres located in the body
-spinal cord
-brain
what passes along nerve cells
electrical impulses
homeostatis relies on …..
negative feedback
for when the levels of something get too high theyre brought back down, and when something get too low theyre brought back up
If our body temperature gets too high, negative feedback will cause our temperature to
decrease back down
what is the purpose of the nervous system
to detect changes in the environment (stimuli) and to coordinate responses
Name 4 different parts of a nervous system
-Central Nervous System
-Sensory neurones
-motor neurones
-effectors
what is the Central Nervous System composed of
-brain
-spinal cord
connected to the body by sensory and motor neurones
what is the gap between two neurone called
synapse
whats released across a synapse
chemicals
what is the sensory neurone
-the neurones that carry information as electrical impulses from the receptors to the CNS
whats a motor neurone
-neurones that carry electrical impulses from the CNS to effectors
what are 2 receptors
-taste on the tongue
-sound in the ears
what does the central nervous system do
it receives infomation from the receptors and then coordinates a response
What does Homeostasis control?
-Blood glucose concentration
-body temperature
-water levels.
reflex actions control what
everyday bodily functions
e.g breathing and digestion
state the reflex pathway
stimulus—- receptor—– sensory neurone—– relay neurone—- motor neurone—- effector—- response
What are reflexes?
Automatic and rapid reactions which don’t involve conscious parts of the brain. Involve sensory, relay and motor neurones. Control breathing, digestion, avoiding danger
What is the endocrine system?
Glands that secrete chemicals called hormones directly into the bloodstream. Blood carries the hormone to a target organ where it produces an effect. Slower but longer lasting
What is the pituitary gland?
Master gland which secretes several hormones into the blood.
