Coordination And Response Flashcards
What does the nervous system consist of?
Brain
Spinal cord
Nerves
Nerve cell is also called
Neurone
What is coordination ?
Making things happen at the right time by linking up different body activities
Which 2 systems do humans have ?
Nervous system
Hormone/endocrine system
What are the common features of both the motor neurone and the sensory neurone ?
- Long fibre (Axon), to carry messages up and down the body
- branches (dendrons), Recife incoming impulses from other neurones
What do motor neurones do ?
They transmit a nerve impulse from the CNS to an effector organ, leading to a response
What is the small gap where two neurones meet called ?
Synapse
What happens over a synapse ?
1) electrical impulses arrive down axon of neurone
2) neurotransmitters released
3) neurotransmitters diffuse across the synapse and attach to membrane of other neurone
4) impulse starts in second neurone
5) neurotransmitters broken down by enzymes of other neurone
What is the flow chart of coordination ?
Stimulus - receptor - coordinator - effector - response
What is a receptor ?
Something that detects the change in environment
They start electrical signals along neurones
What is a stimulus ?
Change in animals surroundings/environment
What is a coordinator ?
What the body decides to do
What does an effector do?
Brings about a response (muscle or gland )
What is a response?
Reaction to change
What is the reflex arc?
The almost instant movement in response to a stimulus
What is the pathway of the reflex arc?
Stimulus Receptor Sensory neurone Relay neurone Motor neurone Effector Response
Nervous system
Works by nerve impulses transmitted through nerve cells
Impulses travel fast
Short lived response
Localised effect
Endocrine system
Works by hormones transmitted through bloodstream
Travel slowly
Long lasting response
Widespread effect
Blood glucose regulation
1) increase blood glucose after eating
2) pancreas detects rise
3) releases insulin
4) insulin travels in blood
5) reaches muscles and liver
6) stimulates uptake of glucose from blood
7) decrease in blood glucose
8) returns to normal
Type 1 diabetes
Stops insulin production
Wee a lot
Destroys cells in pancreas
Type 2 diabetes
Tissues become resistant to insulin
What does the pancreas produce
Glucagon - breaks down glycogen, increases blood glucose
Pupil
Lets light through
Lens
Focusses light, changes shape
Iris
Controls the amount of light entering the eye, contracts or relaxes to dilate or construct pupils
Conjunctiva
Protects eye
Ciliary muscles
Contract or relax to pull dispensary ligaments
Suspensory ligaments
Slack/right to change the shape
Choroid
Contains many pigment cells and blood vessels
Blood supply - stops light reflecting
Retina
Light sensitive layer
Light energy converged into electrical energy of nerve impulses
What does the retina contain
Cones and rods - receptor cells
What do cones do
They detect colour - red, green and blue
What do rods do
Work at night
What happens to your eye in bright light?
Circular muscles contract
Radical muscles relax
Pupil constricts
What happens to your eye in dim light ?
Circular muscles relax
Radical muscles contract
Pupil dilates
What is homeostasis?
The process by which the body maintains a constant internal environment
How does ur body keep warm
Shivering
No sweating
Vasoconstriction
Increased metabolism
How does ur body keep cool
No shivering Sweating Vasodilation Hairs lie flat Decreased metabolism
Skin when cold
Less sweat on surface, less evaporation, less heat loss
Arteriolar constricts (vasoconstriction), less blood flows near the surface
Skin when hot
More sweat on surface, water evaporates, takes heat from skin and blood
Arteriole dilates (vasodilation), more blood flows near skin surface
What are tropisms ?
The growth of a plant in response to a stimulus
Phototropism
Light
Shoots grow towards light source, roots don’t respond
Geotropism
Gravity
Shoots grow away from direction of gravity, roots towards
Opaque cap on tip
No bending
Tip replaced on mica sheet
No bending
Tip replaced on gelatine block
Normal bending
What is the stimulus of growth
Passes through materials which absorb water soluble chemicals
What is auxin
Plant hormone produced in stem tip, promotes cell elongation
Cells in stems grow more
Cells in roots grow less
Adrenaline
Source - adrenal glands
Increases breathing rate, heart rat, flow of blood to muscles, conversion of glycogen
Insulin
Source - pancreas
Controls blood glucose levels Increases conversion of glucose into glycogen for storage
Testosterone
Regulates sex drive, bone mass, sex hormone
Progesterone
Steroid hormone released by the corpus leteum, stimulates the uterus to prepare for pregnancy
Oestrogen
Female sex hormone, development and regulation of female reproductive system
