Test 3 Info Flashcards
Smooth muscle contraction is under ______ control of the nervous system
involuntary
Single unit muscle cells contract _____.
together
in unison
Thin filaments in smooth muscle cells contain the proteins ______ (2)
Actin
Tropomyosin
Caveolae
Invaginations of the plasma membrane
Increase the surface area of the sarcolemma of smooth muscle
Dense plaque
Points where intermediate filaments are anchored to the inner surface of the sarcolemma of smooth muscle
Varicosity
A vesicle (bead) that stores norepinepherine at the terminal branches of ganglionic sympathetic neurons
The z discs that anchor the sarcomere on either end in skeletal muscle are ____ from smooth muscle cells
absent
Do smooth muscle cells have transverse tubules?
No
Smooth muscle cells have a single, centrally located
nuleus
Examples of locations for smooth muscle:
1) In the wall of the small intestine
2) Around blood vessels
3) In the wall of the uterus
In smooth muscle, thin filaments are attached to ____ by elements of the cytoskeleton
dense bodies
Smooth muscle contraction is ___, resistant to ___ and usually sustained for ______ periods of time.
slow
fatigue
extended
Locations for multiunit smooth muscle:
1) Arrector pili muscles
2) Iris of the eye
The sarcolemma of smooth muscle cells has small invaginations called ____
caveolae
During contration of smooth muscle, ____ binds to calcium and activates myosin light chain kinase
calmodulin
The mechanism of contraction in smooth muscle involves a calcium-binding protein called _____
calmodulin
Autonomic motor neurons that control smooth muscle contraction have bulbous swellings called ____ that contain synaptic vesicles.
varicosities
Ohm’s Law
Voltage = Current * Resistance Current = Voltage/Resistance Resistance = Current/Voltage
_____ occurs when the inside of the cell becomes more positive than the resting membrane potential
Depolarization
What 2 things must happen in order for a chemical signal to change the membrane potential of a neuron?
1) Change in # of open ion channels
2) Change in ion flow across the membrane
Compare properties of neuron to electrical currents:
1) Charged particles
2) Voltage
3) Resistance
4) Current
1) Ions
2) Membrane potential
3) Plasma membrane
4) Flow of ions through ion channels
The opposition to the movement of electrical charge is known as ____
resistance
Voltage is a measure of relative _____ _____.
Potential energy
2 basic causes of the development of the resting membrane potential
1) Na+ leak channels
2) K+ leak channels
The resting membrane potential is measured in _____
millivolts (mV)
In the initial segment, an action potential is generated if the membrane potential reaches the ___ ___
threshold value
Current
Movement of charged particles
What channels open and in what order do they open to develop an action potential?
1) Voltage gated Na+
2) Voltage gated K+
What type of channels are essential for the generation of an action potential?
Voltage gated channels
Graded potential
Temporary change in membrane potential which lasts only as long as the stimulus that causes it and can vary in size
Opening of what 2 types of channels would likely lead to hyperpolarization of a neuron?
1) voltage gated potassium channel
2) chemically gated chloride channel
What 2 things would follow after threshold voltage is reached due to sodium ions entering through a voltage gated Na+ channel?
1) Membrane potential would reverse (become positive)
2) More voltage gated sodium channels would open
What is the typical resting membrane potential of a neuron?
-70 mV
What is a central function of neuron physiology?
Creating electrical current
Transmitting electrical current
3 Cranial meninges (from deepest to superficial)
1) Pia mater
2) Arachnoid mater
3) Dura mater
Cerebral aqueduct
connects the third and fourth ventricles through the midbrain
Functions of the Cerebrospinal Fluid
1) Environmental stability
2) Buoyancy
3) Protection
Arachnoid villi
.
Cavities within the brain are called
ventricles
Which of the meninges is the strongest?
Dura mater
The fourth ventricle merges with the ___ ___ in the spinal cord
central canal
There are ____ ventricles in the brain
4
There are ___ lateral ventricles
2
First and second ventricles are lateral
Meninges
Protective membranes that SURROUND, STABILIZE and PARTITION parts of the brain
The lateral ventricles communicate with the ____ ventricle through an opening called the ____ foramen
third
interventricular
What 3 substances can pass through the blood brain barrier (BBB)
1) some anesthetics
2) nicotine
3) alcohol
____ bathes the exposed surfaces of the CNS
Ceribrospinal fluid (CSF)
Blood-brain barrier
Keeps the neurons in the brain from being exposed to
1) variations in levels of ions and hormones
2) drugs
3) waste products in the bloos
CSF circulates in
1) the ventricles
2) subarachnoid space
CSF is produced by secretion of a fluid from
Ependymal cells
Gray matter is
Nonmyelinated
Cell bodies
White matter is
Myelinated
Axons
How many cranial nerves?
12 PAIRS
The 4 Major Regions of the Brain
1) Cerebrum
2) Diencephon
3) Brainstem
4) Cerebellum
Cerebrum
Divided into LEFT and RIGHT CEREBRAL HEMISPHERES
5 Lobes of the cerebral hemispheres
1) Frontal lobe
2) Temporal lobe
3) Occipital lobe
4) Parietal lobe
5) Insula lobe
Gyrus
Hump of a brain fold
On either side of suci
Sulcus
SHALLOW depressions of brain folds
Between gyri
Fissure
DEEP groove in brain
3 Important Sulci
1) Lateral sulcus
2) Central sulcus
3) Parieto-occipital sulcus
Example of a fissure and where it is located
Longitudinal fissure
Between R/L hemispheres
Location of Lateral Sulcus
Between TEMPORAL lobe (below) and FRONTAL/PARIETAL lobes (above)
Relatively horizontal
Location of Central Sulcus
Between FRONTAL lobe and PARIETAL lobe
Relatively verticle
Location of Perieto-occipital Sulcus
Between PARIETAL and OCCIPITAL lobes
Insula lobe
INSIDE brain
Ganglion
Cluster of neuron cell bodies in the PNS
Center
Group of CNS neuron cell bodies with a common function
Nerve
Bundle of AXONS extending through the PNS
Nerve Plexus
Network of nerves
Tract
CNS AXON bundle in which the axons have similar function and share a common origin and destination
Funiculus
Group of TRACTS in a specific area of the spinal cord
Pathway
Centers and tracts that connect the CNS with body organs and sytems
Functions of the cerebrum
Seat of intelligence
1) Information processing
2) Language
3) Personality
4) Conscience
Function of Cerebellum
1) Coordinate motor activities
Parts of the diencephalon
1) Thalamus
2) Hypothalamus
3) Epithalamus
Function of Thalamus
Processing and relay center
Functions of the Hypotalamus
Homeostasis
1) Body temperature
2) Food and water intake
3) Sleep and circadian rhythms
4) Emotional responses
5) Memory
Parts of Epithalamus
1) Pineal gland
2) Habenula
Function of Pineal gland
Endocrine organ (hormones)
Function of Habanula
Relay center
3 Parts of the Brainstem
1) Midbrain
2) Pons
3) Medulla Oblongata
Function of the Midbrain
(part of brainstem)
1) Visual reflexes
2) Auditory reflexes
Function of the Pons
(part of brainstem)
1) Contains ascending and descending fiber tracts
2) Where cerebellar hemispheres are attached
Function of the Medulla Oblongata
(part of brainstem)
1) ALL nerve fibers going between brain and spinal cord pass through
2) Nuclei for Respiration
3) Nuclei for Blood pressure
4) Nuclei for Heartbeat
3 Sensory Cranial Nerves
1) Olfactory (I)
2) Optic (II)
3) Vestibulocochlear (VIII)
5 Motor Cranial Nerves
1) Oculomotor (III)
2) Trochlear (IV)
3) Abducens (VI)
4) Accessory (XI)
5) Hypoglossal (XII)
4 Mixed Cranial Nerves
1) Trigeminal (V)
2) Facial (VII)
3) Glossopharyngeal (IX)
4) Vagus (X)
12 Cranial Nerves in order
1) Olfactory (on)
2) Optic (our)
3) Oculomotor (oak)
4) Trochlear (tree)
5) Trigeminal (Thomas)
6) Abducens (accidentally)
7) Facial (forgot)
8) Vestibulocochlear (valuable)
9) Glossopharyngeal (gold)
10) Vagus (very)
11) Aaccessory (absentminded of)
12) Hypoglossal (him)
12 Cranial Nerve mnemonic
On Our Oak Tree Thomas Accidentally Forgot Valuable Gold Very Absentminded of Him
Olfactory Nerve
I - On
Type SENSORY
Function SMELL
Optic Nerve
II - Our
Type SENSORY
Function VISION
Oculomotor Nerve
# III - Oak Type MOTOR Functions 1) Eyeball movement 2) Raise upper eyelid 3) Pupil constriction 4) Visual focusing
Trochlear Nerve
IV - Tree
Type MOTOR
Function EYEBALL MOVEMENT (lateral and inferior)
Trigeminal Nerve
# V - Thomas Type MIXED Functions 1) Sensory nerve for face 2) CHEWING
Abducens Nerve
VI - Accidentally
Type MOTOR
Function EYEBALL MOVEMENT (lateral)
Facial Nerve
#VII - Forgot Type MIXED Functions 1) Taste 2) Facial expression 3) Control lacrimal (tears) glands 4) Control salivary (saliva) glands
Vestibulocochlear Nerve
# VIII - Valuable Type SENSORY Functions 1) Hearing 2) Equilibrium
Glossopharyngeal Nerve
# IX - Gold Type MIXED Functions 1) Taste 2) Swallowing 3) Control salivary glands 4) Regulate respiration/blood pressure due to sensory association w/ receptor in neck
Vagus Nerve
X - Very
Type MIXED
Functions
1) Sensory signals from motor signals to pharynx, diaphragm, cardiac & smooth muscles
Accessory Nerve
#XI - Absentminded of Type MOTOR Functions 1) Swallowing 2) Sternocleidomastoid & Trapezius muscles
Hypoglossal Nerve
XII - Him
Type MOTOR
Function TOUNGE MOVEMENTS
