Quiz 1 (Chapter 1, 2) Flashcards
brain and behavior
a course that involves the scientific study of how the brain regulates behavior
brain regulates behavior through the _____
central nervous system (CNS)
can the CNS regulate brain behavior?
yes (e.g. repetition in athletes, brain plasticity)
central nervous system (CNS)
consists of brain and spinal cord
anatomy/neuroanatomy
structural analysis, structural vs functional analysis of the brain
chemistry/pharmacology
ions (help structure and function, communication within the brain)
drug interaction (alcohol, cocaine, antidepressants, etc.), what neurotransmitters increase/decrease function of a neuron
physiology
branch of biology
what are the differences
who proposed the neuron doctrine
Ramon y Cajal in the late 1800s
what does the neuron doctrine propose
that the brain is composed of individual, separate cells
neurocytology
the study of nerve cells
sensory neurons (receptors)
highly specialized neurons that encode incoming sensory information
e.g. auditory (afferent)
when these neurons do not operate correctly, it can result in no sense of taste, smell, sight, hearing, or touch
afferent
to, toward CNS
interneurons (associational neurons)
neurons that receive signals from some neurons and send signals to other neurons (think of it like pressing buttons on your phone)
information processors of the nervous system
we do not know much about where they are located, but they make up the majority of our nervous system
motor neurons (effectors)
highly specialized neurons that send signals to muscles and glands
e.g. contracts muscles, moves body parts (efferent)
when these neurons do not operate correctly, it can result in paralysis, etc.
efferent
out, away from CNS
nerve cell membrane
structure that separates the inside (interor) of the cell from the exterior (outside) of the cell
t or f
nerve cell membrane contains channels with pores
true
cell body (soma) contains the ______ and a variety of _________
cell nucleus, intracellular structures
who is the chemical carrier of hereditary
the cell body (soma)
nucleus
center of the cell body, contains chromatin material; is composed of DNA (deoxyribonucleic acid)
what is the first sign of a cell dying
the nucleus moving to the side, found in a lot of Alzheimers patients
nucleolus nickname
recipe book
nucleolus
a separate structure within the nucleus
contains RNA (ribonucleic acid); important; important in the synthesis of proteins
proteins in the nucleolus
structural
enzymatic- break things down (think of hard lens contact story)
endoplasmic reticulum
transports cells and deals with protein folding
golgi apparatus
secrete and transport cells
mitochondria
provide energy to the cell/neuron
dendrite
major receptor surface of the neuron
can be multiple branched or have dendritic spines
dendritic spines
short outgrowths on dendrite branches, can receive messages better
a lot of neurons in the hippocampus (where cognition is important) have dendritic spines
rat experiment (dendrites)
rats were out in two different froups- identical caging, but one with an enriching environment and one without
results for enriching environment:
1. has more extensive dendritic branching pattern
2. has more significant dendritic spines
results can be compared to various childhood upbringings today
axon
single fiber extension originating from cell body (axon hillock) that may be multiply branched
allows for info that travels from axon hillock to tip of axon
typically covered with myelin sheath to speed up the message
if so, has nodes of Ranvier (jumps from gap to gap)
synapse
also called synaptic cleft or gap, very narrow
provide functional contact between cells
.
types of synapses
axodendritic
most common, goes to dendrites
axosomatic
goes to base of dendrites (soma)
axoaxonic
goes to axon hillock
neuromuscular junction (nmj)
info goes from axon to muscle cells
neuron diversity
spinal motor neuron is very long
hippocampal neuron has dendritic spines
cerebellum has no dendritic spines, evolution probably did not catch up with dendritic spines at this point
glial cells
literally means glue
non neural support cells of the nervous system
outnumber neurons by a factor of 10 - 50
microglia vs macroglia
micro- small glial cells
macro- big glial cells
what was different about Albert Einstein’s brain?
he had more glial cells than the average person (helps his neurons work harder and faster)
two times as many astrocytes per neural cell
types of macroglia
astrocytes, oligodendrocytes, ochwann cells, radial glial cells
astrocytes
star shaped cells, higher lipid content, provide structural support and aid in the repair of damaged neurons, helps in the formation of the blood brain barrier (BBB)
oligodendrocytes
only occur in the CNS
provide myelin sheath
ochwann cells
only occur PNS (peripheral nervous system)
radial glial cells
important in the nervous system development
microglia
phagocytes- removes dead tissue from the nervous system
electrochemical transmission “neurotrasmitters”
electrical event –> nerve impulse –> action potential
action potential
the standard event by which info is transmitted down the axon to ultimately have an impact on nerve cell communication
action potential domain exists within the domain
ion channels
pores that can either be opened or closed
selective permeability
ion
an atom, or bound group of atoms that carry an electrical charge (pos or neg)
ionic compound
two or more ions that bind together (e.g. NaCl)
resting membrain potential
-70 mV
neurons maintain an electrical potential difference (a voltage difference) across the cell membrane
at rest, the ion channels are closed (Na, K)
concentration gradient
amount of something (i.e. diffusion of scent of roses; how many ions want to move to a less crowded space); wants to achieve equilibrium
electrical gradient
inside axon is more negative
negative ions want to stay in, positive ions want to stay out
depolarized membrane potential is as a result of __________
Na+ influx
hyperpolarized membrane potential is as a result of __________
K+ efflux
action potential spike threshold
once you reach the threshold, an action potential will happen
it is 15 above the resting (for humans, -55)
refractory period
action potential can not start after one occurs for a period of time, membrane potential is too low
saltatory conduction
moving of action potential down the axon (away from the body)
i.e. jumping down nodes of ranvier
structure of chemical synapses: presynaptic terminal
calcium ion channels (Ca++)
synaptic vesiclas (small round things in the axon)
structure of chemical synapses: synapse
chemically complex fluid
synaptic web (filaments, barely visible, keeps axon and dendrite equidistant)
structure of chemical synapses: postsynaptic membrane
receptor sites (receive message)
ion channels (Na+, K+, Cl-)
exocytosis
Ca++ dependent release of neurotransmitters leaving presynaptic cell
excitatory postsynaptic potential (EPSP)
3 channels open: Na+, K+, Cl-
this is why it is positive
inhibitory postsynaptic potential (IPSP)
2 channels open: K+, Cl-
this is why it is negative
temporal summation vs spatial summation
temporal summation- over time, ap is achieved, EPSPs piggyback off each other
spatial summation- EPSPs merge on the way to axon, make one big EPSP, make an ap
