Unit 2 Human Body Systems PLTW
Terms in this set (73)
Peripheral Nervous System
a nerve network throughout the body, and the function is that nervous cells send info to the CNS from internal organs or from external stimuli
central nervous system
brain or spinal cord and the function is that the brain processes and interprets sensory information sent from the spinal cord. It receives and sends information to the PNS.
sensory somatic cortex
aka post central gyrus. It receives impulses from skeletal muscles, joints, and skin. Examples are muscle cramps, arthritis, or an itch.
motor somatic cortex
CNS to skeletal muscles an example would be lifting your arm up, or just all voluntary movements in general.
six parts of the brain
frontal lobe, parietal lobe, temporal lobe, occipital lobe, cerebellum, and the brainstem
left frontal lobe
used for logic, thinking, rationalizing etc
right frontal lobe
used for dreaming and peoples artistic sides
contains the motor sematic cortex and the sensory sematic cortex ex. pain, cognition, spatial orientation
hearing sound interpretation like knocking or music, and olfactory/smelling sense
A region of the cerebral cortex that processes visual information
used for balance when moving and when being still, also for muscle coordination.
part of brain in charge of involuntary actions aka visceral activities such as breathing, also body temp
A hindbrain structure that connects the medulla to the two sides of the cerebellum; helps coordinate and integrate movements on each side of the body
Controls vital reflexes. Regulation of breathing, heart rate and blood pressure.
is a multi-polar neuron sends impulses from CNS to PNS
uni-polar neuron except for in ears and eyes where they are bipolar neurons it sends impulses from PNS to CNS
They are bipolar neurons that connect motor neurons to sensory neurons so in the spinal cord we have motor and sensory neurons that interneurons will connect so they can communicate with each other.
a chemical that activates a neuron
is the ability to send an impulse (axon)
is the ability to receive an impulse (dendrites)
When the outside of the neuron is positive when compared the inside of the neuron.
Potassium Sodium pump
ensures that more positive ions remain outside the neuron than inside so as to reach resting potential.
drives the potassium/sodium pump
A rapid brief electrical current pulses down the length of an axon to transmit a nerve impulse
when inside of the neuron becomes positive
the act of a neuron again becoming more positive on the outside than in.
how do neurons communicate?
a chemical reaction that occurs between neurotransmitters and cell membrane are how neurons transmit signals to eachother
how can neurotransmitters be stopped
diffusion, enzymatic degradation, glial cells, or reuptake
examples of neurotransmitters
dopamine, serotonin, epinephrine
are specialized sites for neurotransmitters
4 steps in action potential to send a nerve impulse
resting potential, depolarization, repolarization, back to resting potential
myelin sheath and schwann cells
they insulate axons so that action potential can travel more quickly and directly.
there remains a ratio of 3 sodiums outside to ever 2 potassiums inside the neuron
adapts to changes to slow stimuli
messengers within the endocrine system
senders in the endocrine system
receivers in the endocrine system
a muscle that controls how much light enters the eye. It is suspended between the cornea and the lens. Determines the size of the pupil
A clear flexible structure that makes an image on the eye's retina. It is flexible so that it can change shape to focus on objects of varying distance
The thick clear jelly that helps give the eyeball its shape and provides nutrients to the eye.
the thick, tough, white outer covering of the eyeball, protection
the colorful shiny material located behind the retina. It reflects light back through the retina so we can see in dimmer places better.
the bundle of nerve fibers that carry information from the retina to the brain.
the place where the optic nerve leaves the retina, there are no light sensitive cells
the layer of light sensitive cells at the back of the eye. It detects images focused by the cornea and the lens. contains rods and cones
focusing, this is so you can focus on near and far things
the is the dark circle in the center of your iris. It's a hole that lets light into the inner eye.
tough clear covering over the iris and the pupil that helps protect the eye. Light bends as It passes through it.
the bending of light
a clear fluid that helps the cornea keep its rounded shape, also provides nutrients to the corne
sender messenger and target of thyroid gland
target cell: every cell
outcome: regulate metabolism
sender messenger and target of adrenal gland
Outcome: regulates heart rate.
sender messenger and target of the thymus gland
target: red bone
outcome: produce white blood cells
sender messenger and target of testes
target: male reproductive system
outcome: growth of it
sender messenger and target of ovaries
target: female reproductive parts
outcome: growth of it such as breasts, also menstrual cycle
sender messenger and target of pancreas
target: glucose in bloodstream
outcome: lowering of levels of sugar in blood
sender messenger and target of pituitary gland
outcome: smooth muscles of uterus contract during child birth so as to push the child from the mother.
sender messenger and target of pineal gland
target: body cells
outcome: regulates wake-sleep cycles
the function is to receive information from an axon and to also pass that information on
the function is to transmit information to another neuron, muscle, and glands
the function of this is to increase the speed with which an impulse travels across an axon
inside myelin sheath, pretty much the same as myelin sheath but it's a cell
node of ranvier
gap between myelin sheaths on a neuron
these send nerve signals to different parts of the body. It is part of a neuron
play on how we see things and what our brain understands
Quirk, jerky movements of the eyes as they jump from one fixation to another. Lifeguards use it.
nearsightedness; the lens is unable to flatten enough which results in an image forming too early caused because eyeball is too long or lens is too strong.
A lens that is thinner in the center than at the edges; used to fix myopia.
farsightedness; lens is unable to curve enough so the image forms behind the retina, lens is too long or eyeball is too short.
A lens that is thicker in the middle than at the edges; used to fix hyperopia
Abnormal curvature of the eyeball so that rays of light are not focused on a single point on the retina.