| what does the nervous system consist of? | central nervous system: brain and spinal cord |
| name the three main parts of the brain | the cerebrum, cerebellum and medulla |
| name each part of the brain from this diagram | A - Cerebrum
B - Cerebellum
C - Medulla |
| what is the function of the cerebrum | responsible for conscious thoughts, reasoning, memory and emotions |
| what is the function of the cerebellum | controls balance and coordinated movement |
| what is the function of the medulla | controls heart rate and breathing rate |
| what are the three types of neurons? | sensory neuron, inter neuron, motor neuron |
| what is the function of the sensory neuron | transmits an electrical impulse from receptors in sensory organs to the inter neuron in the CNS |
| what is the function of the inter neuron | operates wihtin the CNS, which processes information from senses that require a response
transmits an electrical impulse thrugh the cns from a sensory neuron to a motor neuron |
| what is the function of the motor neuron | transmits an electrical impulse from the cns to the effectors to enable a response to occur at an effector (muslcle or gland) |
| what do receptors detect | stimuli |
| what do electrical impulses have to cross to transfer messages between nuerons | electrical impulses carry messages along neurons and chemicals transfer these messages between neurons, at synapses |
| what is the function of reflexes | to protect the body from harm |
| what is a reflex action | a rapid, automatic, involuntary response to a stimulus |
| is the brain involved in reflex action | no |
| name examples of reflex actions | knee jerk reflex
blinking
iris reflex
response to pain/ limb withdrawal |
| describe the reflex arc of limb withdrawal due to heat | heat receptors in the skin are stimulated by heat from cooker
electrical impulse is sent up the sensory neuron to the spinal cord
onece in spinal cord, elctrical impulse crosses synapse to the inter neuron, where it is processes
electrical impulse crosses another synapse to a motor neuron
electrical impulse travels down the motro neuron to the muscle, effector
muscle in the arm contracts to carry ou the rapid automatic involunary response of moving the arm away from the heat |
| describe the arc of a hearing a fly buzz and swatting it away | a stimulus, buzzing fly is detected by receptors in the ear
receptors send electrical impulse along sensory neuron to inter neuron in the cns.
the inter neuron in the cns processes this information and sens and electrical impulse to and along a motor neuron
electrical impulse is sent from motor neuron to muscle, effector, and the response is the swat the fly away |
| swatting a fly away is an example of | voluntary response to a stimulus
involves conscious thought |
| what is a synapse? | a gap between the end of one neuron and the next neuron
chemicals called neurotransmitters transfer messages between neurons at synapses |
| what is the function of endocrine gland | release hormones into the bloodstream |
| what are hormones | chemical messengers |
| what type of cell do target tissues have | cells with complementary receptor proteins for specific hormones, so only that tissue will be affected by these hormones |
| what is insulin | a hormone produced by pancreas which triggers glucose conversion into glycogen |
| what is glucagon | a hormone produced by the pancreas which triggers glycogen conversion into glucose |
| what is glycogen | stored carbohydrates |
| what is the function of the pancreas? | it is the organ that produces digestive enzymes and the hormones glucagon and insulin |
| what is the liver? | the large organ involved in blood glucose controls |
| what organ detects glucose in the blood | pancreas |
| Describe what happens when blood glucose levels in the body are too high | cells in the pancreas detect the level of glucose in the blood. If blood levels are higher than normal the pancreas will produce the hormone insulin. Insulin will convert excess glucose into glycogen and store it in the liver. This reduces the level of glucose in the blood. |
| Describe what happens when blood glucose levels in the body are too low | Cells in the pancreas detect the level of glucose in the blood. If glucose levels are lower than normal, the pancreas will produce the hormone glucagon. Glucagon will break down glycogen in the liver into glucose. This then helps to raise blood glucose levels. |
