science Flashcards
What is the endocrine system
- a collection of hormone-secreting glands in the body
- responses are slow though long-lasting
- responds to stimuli by secreting hormones into blood
- connected by bloodstream only
what do hormones do
- regulates metabolism, tissue function, sexual function, mood, growth & development.
what is the nervous system responsible for
- in controlling bodily fluids
- made from a network of nerves & cells transmitting signals to & from the body
- response can be fast or slow depending on neurons
- responds by detecting signals from receptors
- transmits signals through sensory, inter-neurons and motor neurons
- connected by nerves/cells/neurons
what is the central nervous system
- includes brain & spinal cord
- control center of body
- ## processes & responds to all messages from PNS
what is the peripheral nervous system
- autonomic & somatic nervous system + sub parts
- ## transmits sensory & motor impulses through nerves
what does the somatic nervous system do
- controls voluntary movements
walking, eating a cake, riding a bike
what does the autonomic nervous system do
- controls involuntary movements
heartbeat, breathing, blinking
differences of nervous systems
- CNS consists of inter-neurons, PNS consists of sensory & motor neurons
what are the main parts of the brain
Cerebrum , cerebellum, brain stem
what is the brain stem
- base of brain
- responsible for other involuntary actions like heartbeat, digestion & breathing
what is the cerebrum
- largest part of brain
- controls voluntary actions, 5 senses & conscious thoughts
what is the cerebellum
- small part of brain behind cerebrum
- coordinates muscular activity without you having to think about it (involuntary actions)
facts
- neurons are cells that transfer electrical messages
-
what are the types of neurons
sensory, motor & inter-neurons
parts of a cell
cell body, dendrites, axon, myelin sheath, terminal branches of axon
what is the cell body
support center/ the cells life
define dendrites
in charge of receiving messages from other cells
define axon
passes messages away from cell body to other neurons, muscles or glands from dendrites
define myelin sheath
covers axons & helps speed neural impulses through axon
define terminal branches of axon
form junctions
define sensory neurons
- transmits detected stimuli
- receptors specialised nervous tissue sensitive to a specific stimuli
define motor neurons
- sends impulse from brain & spinal cord to other systems
- allows body to react to stimuli
define inter neurons
- found in brain & spinal cord
- carry messages from 1 part of CNS to another
- interconnect the sensory neurons with appropriate motor neurons
define receptors
- group of specialised cells detecting change in environment (stimuli) turning into impulses
- sensitive to 5 senses
define effectors
- react to command
what is a relfex action
- involuntary actions only going from spinal cord & back through body
- usually reacting from danger
extra parts of brain
right cerebral hemisphere - perception, decision making, language, consciousness= human experiences left cerebral hemisphere - joined with thick bridge of white tissues (corpus calliosum) pons - important for attention medulla oblongata - houses breathing control centers
what is the synapse
- neurons do not touch
- gap between 2 nerve cells
- electrical impulse releases chemicals called neurotransmitters transmitting signals across synapse
what is a neurotransmitter
a chemical messenger which transmits signals across a chemical synaps from one neuron to another target neuron, muscle, gland
what is homeostasis
- ability to maintain a constant internal balance in response to change
- occurs when there is an imbalance in nervous system
- the balance in our body for negative feedback
homeostasis cycle
stimulus > sensor > control > effector > negative feedback loop
what is the endocrine system made of
- ovaries/testes
- adrenal glands
- pancrease
- thymus
- thyroid gland
- pituitary gland
- hypothalamus
pineal gland
types of diabetes
Type 1 - insulin dependent, more severe Type 2 - non-insulin dependent Diabetes mellitus - most common
what is diabetes
- when blood glucose is too high
- Insulin, a hormone made by the pancreas, helps glucose from food get into your cells to be used for energy
define glucagon
- promotes the breakdown of glycogen to glucose in the liver
- increases blood sugar
