Section 1: Cells and the Anatomy of the Brain Flashcards
Review/Learn Section I of the Science Pentathlon 23-24 Study Guide.
Where is the nucleus of a neuron located?
the soma or cell body
What is the main role of the nervous system?
communication
What is the receiving part of a neuron?
the dendrite
The word dendrite comes from the Greek word for _________.
treelike
What part of the neuron sends signals down?
the axon
Where does the axon end?
axon terminals
Are there organelles in the axon?
no
Where does the axon begin?
the axon hillock
What are the gaps in myelin called?
Nodes of Ranvier
At what part of a neuron does another neuron connects and transmits signals to another?
the synapse
In the brain, what type of matter is on the outside?
gray matter
In the spinal cord, what type of matter is on the outside?
white matter
What are the non-neuronal cells in the nervous system?
glial cells, or GLIA
Glial cells were first thought to have which function in the nervous system?
The function of holding the neurons together
What types of GLIA myelinate axons?
oligodendrocytes and Schwann cells
Oligodendrocytes myelinate neurons in which part of the nervous system?
the central nervous system
Schwann cells myelinate neurons in which part of the nervous system?
the peripheral nervous system
What GLIA regulates the chemical makeup of the nervous system?
astrocytes
What cells are immune cells of the nervous system?
Microglia
What does the latin word Dura Mater mean?
Tough Mother
What is the outermost layer of the meninges?
the Dura Mater
What fatty layer is between the dura mater and skull and absorbs shock?
the epidural space
What is the second layer of the meninges?
the Arachnoid membrane
What layer is found below the arachnoid membrane?
the subarachnoid membrane
What is the 3rd layer of the meninges?
the Pia Mater
“Pia Mater” comes from the Latin words for?
gentle mother
What is the largest part of the brain?
the cerebrum
What are gyri
the bumps on the brain’s surface
What are sulci?
the grooves and folds on the brain
How many lobes of the brain are there?
4
What is the largest lobe?
the frontal lobe
The frontal lobe has regions related to?
complex thinking, motor planning, cognition, and more
The parietal lobe has regions related to?
processing sensory and spatial information
The temporal lobe has regions related to?
processing auditory information, memory, emotion, recognition, and more
The occipital lobe has regions related to?
processing visual information
The cerebellum is involved in what functions?
learning new movements, coordination, and other motor functions
The cerebellum is 10% of the brain’s mass, but has over __% of the brain’s neurons.
50%
Amygdala comes from the Greek word meaning __________.
almond
The limbic system is a major system for what?
behavior and emotions
The amygdala does what?
Regulates fear and other emotions and processes stress, threat, reward
The hippocampus is good for?
long-term memory and spatial navigation, as well as how the circuitry of the brain changes over time
The thalamus is the ________ __________ between the body and the brain
Relay station
All sensory input must pass through the thalamus except for what?
smell or olfaction
The hypothalamus works to intervene and balance out with which other brain region?
the pituitary gland
What is homeostasis?
homeostasis is a state of the body where all systems are perfectly balanced and is an ideal state
The pineal gland regulates sleep patterns by producing what hormone?
Melatonin
What is Melatonin?
Melatonin is the hormone that causes you to fall asleep
How does the pineal gland know when to produce Melatonin?
It takes visual information and produces it when it is dark out or when your body feels tired
The basal ganglia is best known for its role in movement, but also plays a role in ___________________________.
motor learning, cognition, behavior, and emotion
What are the structures that make up the basal ganglia?
the putamen, caudate nucleus, and substantia nigra
What part of the basal ganglia dies off with Parkinson’s disease?
the substantia nigra
What are symptoms associated with Parkinson’s disease?
muscle rigidity, a gait, and difficulty initiating movement
What is a gait?
too little or too much movement when walking
What are the sections of the brainstem?
the midbrain, pons, and medulla oblongata
What is the topmost part of the brainstem?
the midbrain
What is the middle part of the brainstem?
the pons
Pons comes from the Latin word for ______.
bridge
What is the bottom part of the brainstem?
the medulla oblongata
What does the midbrain control?
It controls eye movements, as well as making a map of the environment by using visual and auditory information
What does the pons control?
facial movements, balance, hearing, and muscles
What does the medulla control?
touch sensations, vomiting, blood pressure, heart rate, breathing, and other involuntary functions
While the brain is encased in skull, what is the spinal cord encased in?
vertebrae
What does the cervical spinal cord innervate?
The arms, neck, and shoulders
What does the thoracic spinal cord innervate?
chest and torso
What does the lumbar spinal cord innervate with?
hips and fronts of the legs
What does the sacral spinal cord innervate with?
the buttocks, the backs of the legs, the bladder, and the genitals
What are the cavities in the ventricular system filled with?
CSF
In the spinal cord, CSF can be found in a long, narrow tube called the _________ ___________.
central canal
What lines the ventricular system and produces new CSF?
the choroid plexus
What is old CSF absorbed by
the meninges
What are the 2 parts of the peripheral nervous system?
the somatic and autonomic nervous systems
What is the somatic nervous system made up of?
The sending of sensory information, specifically ones from external tissues
True or False: The somatic nervous system consists of two subsections.
False, this is the autonomic nervous system
Can you feel the sensations involved with the somatic nervous system?
Yes, they are under our conscious control
Autonomic comes from which Greek word?
autonomia
Does the autonomic nervous system control the unconscious or conscious responses?
the unconscious responses, specifically the functions of the internal organs
Where is smooth muscle found?
our internal organs
Which Greek word does the word “autonomia” come from?
The word for “independence”
Which division of the autonomic nervous system is responsible for the fight or flight response?
The sympathetic division
The neuron that starts the sympathetic chain is located in which area of the spinal cord?
the lumbar and thoracic regions
The response from the sympathetic division is activated by which glands?
the adrenal glands
The adrenal glands produce what hormone?
adrenaline
While the sympathetic division is focused on “fight or flight” responses, the parasympathetic division is focused on ______ ___ ________.
rest and digest
Where are parasympathetic ganglia found?
near their target organ
What are membrane potentials?
the charge on the inside of the cell compared to the outside
What are membrane potentials measured in (electricity)?
millivolts or mV
A membrane potential of ____ means the charge of the inside of the neuron is the same as the outside environment.
0 mV or 0 millivolts
The resting and action potentials can be compared to ______________________.
the turning on and off a light switch
What are the 3 types of ion channels?
Sodium (Na), Chlorine (Cl), and Potassium (K)
In a resting state, is the inside of the neuron more or less negatively charged than the outside?
more negatively charged
What is a typical resting potential voltage?
-70 mV
What does depolarization mean
To become more positive
What does repolarization mean?
To become more negative
What is the all-or-none principle?
This refers to when a neuron’s potential reaches threshold and keeps polarizing, or doesn’t reach threshold and depolarizes back to resting state.
What is the voltage for threshold?
-50 to -65 mV
Polarization occurs until it reaches the overshoot of the action potential or _______ mV.
30 to 40 mV
What is the propagation of an action potential?
the rapid opening and closing of ion channels to start an action potential
When the action potential reaches its peak, what channels open and what channels close?
Na channels close and K channels open, allowing potassium to flow out of the cell
The cell will repolarize after the overshoot until it reaches what voltage?
-80 mV
What allows the cell to return to a normal resting potential after the undershoot?
the sodium-potassium pump
Does the sodium-potassium stop working?
No, unless there is something wrong with the cell or the neuron dies off
What type of cell allows for neurons to communicate?
Astrocytes
What is neuroscience?
the study of the nervous system
What is a presynaptic neuron?
the neuron that synapses onto another neuron
What is a postsynaptic neuron?
a neuron that receives information from the presynaptic neuron
Do interneurons have axons?
no
Hyperactive microglia cause what in the brain?
inflammation
Where is the prefrontal cortex located?
in the frontal lobe, all the areas in front of the motor cortex
What is memory consolidation?
the process of creating long-term memories, usually by making short-term memories into more-stable long term memories
Smell doesn’t pass through the thalamus, but instead goes directly to which brain area?
the amygdala
What are hormones?
the chemical messengers of the brain
