Neuroscience
Chapter 2, Section 1:
Questions Answers / Notes
What is the Neuron? ● to understand our behavior and mental processes, we
need to understand their biological underpinnings,
starting with the cellular level, the neuron
What is the structure of a neuron? ● the brain and the nervous system are composed of tw
types of cells - neurons and glial cells
● Neurons- cells that transmit information within the
nervous system
● Glial cells comprise the support system for the neuro
90% of the cells in the brain are glial cells. Glial cells
communicate with each other in a separate but parall
network to the neuronal network, influencing the brain
performance. Important role in mental disorders such
schizophrenia, and depression, and in neurodegenera
diseases such as Parkinson's and Alzheimer's
● Three main components of a neuron are the dendrites
cell body, and axon.
● Dendrites- fibers projecting out of the cell body of a
neuron whose function is to receive information from
other neurons
● Cell body- the part of the neuron that contains its
nucleus and the other biological machinery to keep th
cell alive and that decides whether or not to generate
neural impulse in order to pass incoming information
the other neurons
● Axon- the long, singular fiber projecting out of the cell
body of a neuron whose function is to conduct the ne
impulse from the cell body to the axon terminals
triggering chemical communication with other neuron
Spinal cord to the toes
,figure 2.1 the structure of a neuro
How do neurons communicate? ● the process is partly electrical and partly chemical
● It's an electrical impulse is generated and travels dow
the axon
● Separated by a microscope gap that chemical molecu
travel across to carry their message
What is the electrical impulse? ● begins with the messages received by the dendrites f
other neurons
● Inputs are either excitatory (telling the neuron to
generate an electrical impulse) or inhibitory (telling th
neuron not to generate an electrical impulse)
● Cell body decides whether or not to generate an impu
by continually calculating this input
● Excitatory input outweighs the inhibitory input by a
sufficient amount, then the cell body will generate an
impulse
● Myelin sheath- an insulating layer covering an axon th
allows for faster neural impulses
● No myelin sheath the impulse travels slowly down the
axon in a continuous fashion
● Myelination creates whitish appearance because of th
white color of the myelin
● Unmyelinated part of neuron appear grayish
How is chemical communication ● neurotransmitter- a naturally occurring chemical In th
between neurons? nervous system that specializes in transmitting
information between neurons
● Synaptic gap (synapse)- the microscope gap between
neurons across which neurotransmitters travel to car
their messages to other neurons
, figure 2.2 synaptic communicatio
between neurons
What are brain scans? ● in order to carry out essential communication work,
neurons require oxygen and other nutrients such as b
sugar
● About 20% of the body's blood supply is pumped to th
brain, and the brain consumes about a quarter of the
body's oxygen
● Without oxygen neurons die within minutes
● Positron emission tomography (PET）scans a visua－
dispIay of the activity leveIs in various areas in the bra
generated by detecting the amount of positron emiss
created by the metabolization of radioactive glucose
each area. Often used to tell us which areas are most
active and thus more involved while a person perform
Chapter 2, Section 1:
Questions Answers / Notes
What is the Neuron? ● to understand our behavior and mental processes, we
need to understand their biological underpinnings,
starting with the cellular level, the neuron
What is the structure of a neuron? ● the brain and the nervous system are composed of tw
types of cells - neurons and glial cells
● Neurons- cells that transmit information within the
nervous system
● Glial cells comprise the support system for the neuro
90% of the cells in the brain are glial cells. Glial cells
communicate with each other in a separate but parall
network to the neuronal network, influencing the brain
performance. Important role in mental disorders such
schizophrenia, and depression, and in neurodegenera
diseases such as Parkinson's and Alzheimer's
● Three main components of a neuron are the dendrites
cell body, and axon.
● Dendrites- fibers projecting out of the cell body of a
neuron whose function is to receive information from
other neurons
● Cell body- the part of the neuron that contains its
nucleus and the other biological machinery to keep th
cell alive and that decides whether or not to generate
neural impulse in order to pass incoming information
the other neurons
● Axon- the long, singular fiber projecting out of the cell
body of a neuron whose function is to conduct the ne
impulse from the cell body to the axon terminals
triggering chemical communication with other neuron
Spinal cord to the toes
,figure 2.1 the structure of a neuro
How do neurons communicate? ● the process is partly electrical and partly chemical
● It's an electrical impulse is generated and travels dow
the axon
● Separated by a microscope gap that chemical molecu
travel across to carry their message
What is the electrical impulse? ● begins with the messages received by the dendrites f
other neurons
● Inputs are either excitatory (telling the neuron to
generate an electrical impulse) or inhibitory (telling th
neuron not to generate an electrical impulse)
● Cell body decides whether or not to generate an impu
by continually calculating this input
● Excitatory input outweighs the inhibitory input by a
sufficient amount, then the cell body will generate an
impulse
● Myelin sheath- an insulating layer covering an axon th
allows for faster neural impulses
● No myelin sheath the impulse travels slowly down the
axon in a continuous fashion
● Myelination creates whitish appearance because of th
white color of the myelin
● Unmyelinated part of neuron appear grayish
How is chemical communication ● neurotransmitter- a naturally occurring chemical In th
between neurons? nervous system that specializes in transmitting
information between neurons
● Synaptic gap (synapse)- the microscope gap between
neurons across which neurotransmitters travel to car
their messages to other neurons
, figure 2.2 synaptic communicatio
between neurons
What are brain scans? ● in order to carry out essential communication work,
neurons require oxygen and other nutrients such as b
sugar
● About 20% of the body's blood supply is pumped to th
brain, and the brain consumes about a quarter of the
body's oxygen
● Without oxygen neurons die within minutes
● Positron emission tomography (PET）scans a visua－
dispIay of the activity leveIs in various areas in the bra
generated by detecting the amount of positron emiss
created by the metabolization of radioactive glucose
each area. Often used to tell us which areas are most
active and thus more involved while a person perform
