Anatomy 31 test review
what are the structures of the eye?
cornea, iris, pupil, retina, rods, and cones
what is the job of the brain?
processes and relays information
interneuron
processes information from sensory neurons and send commands to motor neurons
thalamus
receives messages from sensory receptors and relays information to cerebrum
hypothalamus
recognition of hunger, thirst, fatigue, anger, and body temperature
what does the autonomic nervous system do?
regulates activities that are involuntary
what does the somatic nervous system do?
regulates body activities that are under conscious control like movement of skeletal muscles
what helps you maintain balance?
semicircular canals and the sacs are filled with fluid and lined with hair cells; as the head moves, the fluid in the canals changes positions; hair cells bend and send impulses to brain to determine body positions
rods
sensitive (detects) to light
what 2 divisions make up the peripheral nervous system?
sensory and motor divisions
what are thermoreceptors?
sensory receptors that respond to heat and cold
what are the types of neurons?
sensory, motor, and interneuron
what is considered to be the largest sense organ and why?
skin; nearly all regions are sensitive to touch
what is the job of the motor division?
transmits impulses from the central nervous system to muscles or glands
retina
where the lens focuses light; where the photoreceptors are found
where is the only place in the body where there are no pain receptors?
brain
what does the central nervous system comprise of?
brain and spinal cord; processes information and creates response
why do addicts need more and more drugs?
brain decreases the number of receptors so dopamine is not released as much
what is the sympathetic nervous system?
"fight or flight"; increase heart rate, increases blood pressure, increases 02, and releases of glucose
what is the parasympathetic nervous system?
"rest or digest"; decrease heart rate, decreases blood pressure, and activates digestion
explain what happens if someone steps on a nail
1. sensory receptors react ot anil and send an impulse to sensory neurons 2. sensory neurons relay information to spinal cord 3. spinal cord interneuron processes information and forms a response 4. a motor neuron carries impulses to effectors (muscle) 5. muscle contracts
how is sound formed?
1. vibrations enter the ear and cause tympanum (ear drum) to vibrate 2. hammer, anvil, and stirrup transmit impulses to oval window 3. vibrations create pressure waves in cochlea and move the hairs 4. hair cells send nerve impulses to brain which processes impulses as sounds
what is a strong stimulus?
100 action potentials per second
what is a weak stimulus?
3-4 action potentials per second
what is the job of the sensory division?
transmits impulses from sense organs to the central nervous system
what are the umami receptors?
a 5th kind of taste sensation stimulated by the MSG (monosodium glutamate)
how do sodium and potassium ions create a resting potential?
active transport bumps and sodium out of the cell and potassium into the cell
cerebellum
actively learns movement and coordinates the actions of muscles
lens
adjust the eyes to focus on near or distant objects
what happens in order for a voluntary movement to take place?
brain impulses are carried through the spinal cord and synapse with motor neuron dendrites; motor neuron axons carry impulses to muscles
sensory neurons
carries impulses from sense organs to spinal cord and brain
motor neurons
carry impulses from brain and spinal cord to muscles or glands
what are the parts of a neuron? and explain each part
cell body: contains nucleus and forms responses dendrite: receive impulses axon: carry impulses to nearby neuron
what are sensory receptors?
cells that transmit information about changes in the environment ex: pain receptors and chemoreceptors
list the 6 parts of the brain
cerebrum, limbic system, thalamus, hypothalamus, cerebellum, brain stem
what is a neurotransmitter?
chemicals that transmit an impulse across a synapse to another cell ex: serotonin and dopamine
What is the job of the nervous system?
collects information, process the info, and send responses
iris
colored part of the eye
brain stem
connects the brain and spinal cord; made up of midbrain, pons, and medulla oblongata
cones
distinguishes color
what neurotransmitter is changed by addictive substances?
dopamine
how does the motor division transmit impulses from the central nervous system to muscles or glands?
either through the somatic nervous system or autonomic nervous sytem
cornea
helps to focus light
what parts of the brain release the neurotransmitter?
hypothalamus and limbic system
what is the purpose of the myelin sheath
insulation (protection) and allows impulses to travel faster
cerebrum
largest part of the brain; voluntary activities; site of intelligence, learning, and judgment
what is the job of the spinal cord?
main link between the brain and the rest of the body
what controls hearing and balance?
mechanoreceptors in the brain and the central nervous system (CNS)
what is a threshold?
minimum level of a stimulus that is required to cause and impulse
pupil
muscles of iris adjust to allow light in
what is the covering around the axon called?
myelin sheath
what does the peripheral nervous system comprise of?
nerves and supporting cells; bollects information
What is resting potential?
outside the cell membrane is positively charged and inside is negatively charged; maintained by active transport
what is a reflex arc?
pathway of a rapid response (reflex)
what are the 2 systems that make up the nervous system?
peripheral and central nervous system (CNS)
how does vision work?
photoreceptors (rods and cones) in the eyes transmit impulses to the brain and the brain translates impulses to images
what is an action potential?
sodium gates open and allow sodium to flow into cells, creating a charge reversal; inside of the cell temporarily to positive and outside is negative
limbic system
the pleasure center
what is a synapse?
the point at which a neuron transfers an impulse to another cell
what is the job of this neurotransmitter?
transmit signals from nerve cells to target cells