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