Final AP BIO 141 Exam
A reflex arc is termed 1 when the receptor and effector organs of the reflex are on the same side of the spinal cord. For example, this effect occurs when the muscles in your left arm contract to pull your 2 hand away from a hot object.
1. ipsilateral 2. left
The cerebrum is divided into two halves
1. left hemisphere 2. right hemisphere
Efferent neurons are the neurons of the motor nervous system, conducting ____ output from the CNS to the effectors. All the motor neurons are _____
1. motor 2. multipolar
Overview of Conduction Pathways. 1. Sensory pathways transmit ascending information from sensory _____ to the _____. 2. Whereas, Motor pathways transmit descending information from the ____ to ____ and ____.
1. sensory receptors to the CNS. 2. from the brain to muscles and glands.
Match the location with the larger concentration or ions. 1. Extracellular -> 2. Intracellular ->
1. sodium 2. organic ions
Place the events in the correct sequence
1.) Action potential reaches synaptic knob 2.) Voltage-gated calcium channels open 3.) Calcium enters the synaptic knob 4.) Synaptic vesicles merge with synaptic knob plasma membrane 5.) Neurotransmitter is released by exocytosis 6.) Neurotransmitter crosses synaptic cleft 7.) Neurotransmitter attaches to receptors on a muscle, neuron, or gland cell.
Electrical impulse that travels from beginning with the postsynaptic membrane
1.) Dendrites 2.) Soma 3.) Axon Hillock 4.) Neurofibril node or Node of Ranvier 5.) Synaptic Knobs
EPSP in the correct order from beginning to end
1.) Excitatory neurotransmitter released from presynaptic neuron 2.) Neurotransmitter binds to chemically-gated sodium channels. 3.) Sodium channels open 4.) Sodium flows into neuron 5.) Inside of neuron becomes more positive 6.) EPSP propagates toward axon hillock.
Overview of Events in Skeletal Muscle Contraction
1.) Neuromuscular Junction: Excitation of a Skeletal Muscle Fiber: Release of neurotransmitteracetycholine (ACh) from synaptic vesicles and subsequent binding of ACh to ACh receptors. 2.) Sarcolemma, T-tubules, and Sarcoplasmic Reticulum: Excitation-Contraction Coupling: ACh binding triggers propagation of an action potential along the sarcolemma and T-tubules to the sarcoplasmic reticulum, which is stimulated to release Ca2+. 3.) Sarcomere: Crossbridge Cycling: Ca2+ binding to troponin triggers sliding of thin filaments past thick filaments of sarcomeres; as sarcomeres shorten, the muscle contracts
Generation of EPSP (receptive segment)
1.) Neurotransmitter released from presynaptic neurons binds to postsynaptic neuron receptors, which are chemically gated cation channels, causing them to open. 2.) Na+ flows into neuron (faster than K+ flows out). 3.) Inside of neuron becomes more positive (less negative); called EPSP (e.g., -68mV). 4.) EPSP moves toward the initial segment.
Generation of IPSP (receptive segment)
1.) Neurotransmitter released from presynaptic neurons binds to postsynaptic neuron receptors, which are either chemically gated K+ channels or chemically gated CI- channels, causing them to open. 2.) Either K+ flows out of or CI- flows into the neuron, depending on the type of channel stimulated. 3.) Inside of neuron becomes more negative; called IPSP (e.g., -72 mV). 4.) IPSP moves toward the initial segment.
____ pairs of cranial nerves extend from the brain.
12
neuromuscular junction (NMJ)
1a) A nerve signal triggers voltage-gated Ca2+ channels to open - Ca2+ enters synaptic knob and binds to synaptic vesicles. 1b) ACh is released by exocytosis into synaptic cleft. 1c) ACh binds to ACh receptors
Neuromuscular Junction: Excitation of a Skeletal Muscle Fiber
1a) Ca2+ entry at synpatic knob - A nerve signal is propagated down a motor axon and triggers the entry of Ca2+ into the synaptic knob; Ca2+ binds to proteins in synaptic vesicle membrane. 1b) Release of ACh from synaptic knob - Calcium binding triggers synaptic vesicle to merge with the synaptic knob plasma membrane and ACh is exocytosed into the synaptic cleft. 1c) Binding of ACh to ACh receptor at motor end plate - ACh diffuses across the fluid-filled synaptic cleft at the motor end plate to bind with ACh receptors.
Sarcolemma, T-tubules, and Sarcoplasmic Reticulum: Excitation-Contraction Coupling
2a) ACh binding causes Na+ to rapidly enter the skeletal muscle fiber and K+ to slowly exit the skeletal muscle fiber, which may result in an 2b) The EPP initiates an action potential along sarcolemma and T-tubules. 2c) Action potential triggers Ca2+ release from sarcoplasmic reticulum (SR) terminal cisternae.
Sarcomere: Crossbridge cycling (cycle repeats and sarcomere shortens)
3a) Ca2+ binds to troponin exposing myosin binding sites on actin. 3b) Attach: Crossbridge formation between myosin and actin. 3c) Pull: Power stroke motion of myosin heads pulls thin filament past it. 3d) Release: ATP binds to myosin head releasing myosin head from actin. 3e) Reset: ATP split and myosin head is reset.
Lumbar Nerves (L1-L5)
5 pairs
Sacral Nerves (S1-S5)
5 pairs
Cervical Nerves (C1-C8)
8 pairs
Nervous tissue
A body tissue that carries electrical messages back and forth between the brain and every other part of the body.
Muscle tissue
A body tissue that contracts or shortens, making body parts move.
connective tissue
A body tissue that provides support for the body and connects all of its parts
Describe the anatomical position
Body erect; feet flat, facing forward; eyes facing forward; arms to the side, palms facing forward with thumbs pointing out.
What is the Digestive System responsible for
Breaking down ingested material, absorbing nutrients from this material, and eliminating undigested material
cross section of spinal cord
CENTRAL CANAL, GREY MATTER, WHITE MATTER, POSTERIOR MEDIAN SULCUS, ANTERIOR MEDIAN FISSURE, DORSAL HORN, VENTRAL HORN, DORSAL ROOT, DORSAL ROOT GANGLION, VENTRAL ROOT, and SPINAL NERVE
____ bathes the exposed surfaces of the central nervous system.
CSF
Two directional terms are often used to describe relative position of brain anatomy. Posterior is synonymous with ____.
Caudal meaning "toward the tail"
Divisions of the Nervous System
Central Nervous System (CNS) and Peripheral Nervous System (PNS)
Microscopic anatomy of Spinal cord
Cervical, Thoracic (or brachial), lumbar, sacral cord
Mental
Chin
Proximal
Closer to the origin of the body part or the point of attachment of a limb to the body trunk
Nucleus or center
Clusters of neuron cell bodies within gray matter that are either close to the surface or deep within the brain.
The central nervous system (CNS) communicates with the body through _______ pathways that extend through the spinal cord.
Conduction pathways
What can the Dorsal Cavity (posterior) be subdivided into
Cranial and Spinal Cavities
What is the Endocrine System responsible for
Creates and secretes hormones, occurs slowly and lasts a longer period of time
Sarcomere: Crossbridge Cycling
Crossbridge cycling is initiated by the release of Ca+ from the sarcoplasmic reticulum. This allows myosin heads to bind to actin to pull thin filaments past thick filaments. This process is the sliding filament theory.
Structure and Organization of a Skeletal Muscle Fiber
(a) A skeletal muscle fiber is composed predominately of myofibrils, which extend the length of the muscle fiber. (b) A myofibril is composed of bundles of myofilaments (protein filaments) and is enclosed within segments of the sarcoplasmic reticulum by invaginations of the scarcolemma called T-tubules; both contain voltage-gated Na+ channels and voltage-gated K+ channels. (d) The triad is a T-tubule flanked by two terminal cisternae of the sarcoplasmic reticulum. In this region, the T-tubule membrane contains voltage-sensitive Ca2+ channels and the terminal cisternae membrane contains both ca2+ release channels and Ca2+ pumps.
Which of the following pumps can you find in the plasma membrane?
-Ca2+ -Na+/K+
Epithelia
-Forms the surface of the body -Line body cavities and hollow organs -Constitute most gland tissue -Substances entering or leaving the body must cross the epithelia
Gray matter is composed of ___ horns 1. _____ contains sensory axons and interneurons. 2. _____ contains cell bodies of somatic motor neurons. 3. _____ contains cell bodies of autonomic motor neurons.
-Gray matter is composed of 3 horns. -Posterior contains sensory axons and interneurons. -Anterior contains cell bodies of somatic motor neurons. -Lateral contains cell bodies of autonomic motor neurons.
Lumbar
-L1 to L5 -gives rise to the femoral nerve
Telencephalon are
-Lateral ventricles -Cerebrum
Gray Matter
-Marked by low myelination -Anterior horn -Lateral horn
What chemicals create the charges?
-Potassium (K+) that's in the ICF or inside of cells. -Sodium (Na+) most commonly electrocytes/ions found usually in ECF.
Sensory pathways use what 3 neurons?
-Primary -Secondary -Tertiary
Temporal lobe (retracted)
-Primary auditory cortex -Auditory association area -Primary olfactory cortex
Sacral
-S1 to S5 -gives rises to the sciatic nerve
Diencephalon
-Third ventricle -Structures: Epithalamus, thalamus, hpyothalamus
The time when there is complete insensitivity of the plasma membrane to another stimulus
-absolute refractory period
Functions of Skeletal Muscle
-body movement -maintenance of posture -protection and support -regulating elimination of materials -heat production
Considered types of effectors are...
-cardiac muscle -skeletal muscle -glands
Epimyseum
-dense irregular connective tissue covering of the muscles. -Infiltrated by nerves and blood vessels
Skeletal muscle physiology involves three major events:
-excitation -excitation-coupling -cross-bridge cycling
White matter
-fasciculus gracilis -contains myelinated axons -tectospinal tract -posterior funiculus
Myelencephalon
-fourth ventricle (inferior part); part of central canal. -Medulla oblongata
Metencephalon
-fourth ventricle (superior part) -Structures: Pons, cerebellum
Myelin is critical to nervous system function since it provides insulation for the neuronal axons and facilitates rapid propagation of neural impulses.
-it provides insulation for the neuronal axons and facilitates rapid propagation of neural impulses
Major Organelles of the Cell Body
-large nucleus -cytoplasm -mitochondria -nissl boddies (RER and ribosomes) -cytoskeleton
Thoracic
-nerves innervate intercostals -T1 to T12 -contains no enlargement
The cells of the nervous system that produces myelin are the
-oligodendrocytes
A time when there is a decrease in the sensitivity of the plasma membrane to further stimulation
-refractory period
The time when a stronger than threshold stimulus is needed to initiate another action potential.
-relative refractory period
Triggers of acute episodes of multiple sclerosis are
-stress, infections, and pregnancy
angular gyrus function
1) Involved in mathematical calculation 2) Contributes to cognitive functions 3) Reading and writing
Interneurons (or ____1___ neurons) lie entirely within the CNS. They recieve stimulation from many other neurons and carry out the integrative function of the nervous system. The most numerous types of neurons are ___2___
1. Association 2. Interneurons
The brain is composed of four major regions:
1. Cerebrum 2. Diencephalon 3. Brainstem 4. Cerebellum
Types of Membrane potential:
1. RMP (resting membrane potential) 2. Depolarization - "localized" change in membrane potential @ MEP. 3. Action potential (nerve impulses) - and continuation of depolarization -> muscles will contract! 4. Repolarization - returns to RMP state depends on movement of K+ back into cell.
functional segments:
1. Receptive segment (dendrite-soma, most times) 2. Initial segment (just distal to the axon hillock) 3. Conductive segment (axon) 4. Transmissive segment (synapse) 5. Tropic segment (the soma)
What are the 10 Characteristics of Life
1. Responsiveness 2. Conductivity 3. Growth 4. Respiration 5. Digestion 6. Absorption 7. Secretion 8. Excretion 9. Circulation 10. Reproduction
Afferent neurons are the neurons of the sensory nervous system. They are responsible for conducting ____ input from both somatic sensory and visceral sensory receptors. Most sensory neurons are ____.
1. Sensory 2. Unipolar
Distribution of White Matter 1. White matter is organized into three pairs of ____. 2. Most of which contain ____ (ascending) tracts and ____ (descending) tracts.
1. White matter is organized into three pairs of funiculi. 2. Most of which contain Sensory (ascending) tracts and Motor (descending) tracts.
Neurons are classified functionally according to the direction the _____ travels relative to the ___.
1. action potential 2. CNS
A reflex arc is ____1___ when the sensory impulses from a receptor organ cross over through the spinal cord to activate effector organs in the ___2__ limb.
1. contralateral 2. opposite
Place the events of a chloride-based IPSP in order from earliest to latest
1. inhibitory neurotransmitter binds postsynaptic chemically gated chloride channels. 2. chloride moves from outside the cell to inside. 3. the inside of a postsynaptic cell becomes more negative 4. the local chloride current become weaker as it moves away from the neurotransmitter blinding site
____ occurs when the inside of the cell becomes more positive (less negative) than the resting membrane potential
Depolarization
What are the 2 major body cavities
Dorsal (posterior) and Ventral (anterior)
Negative feedback loop
Dynamic state within narrow ranges Response allows for the narrow fluctuations around a "set point"Brings a deviation (change) in a physiological event back to normal (= reverses change)
Neuromuscular Junction: Excitation of skeletal muscle
Excitation involves the arrival of a nerve signal to stimulate release of the neurotransmitter acetylcholine (ACh) contained within synaptic vesicles.
Sarcolemma, T-tubules, and Sarcoplasmic Reticulum: Excitation-Contraction Coupling of skeletal muscle
Excitation-contraction coupling links excitation of the muscle by the motor neuron to muscle contraction through the sarcolemma, T-tubules, and sarcoplasmic reticulum.
Gross Anatomy of the Spinal Cord
Extends from the Foramen Magnum to L1 or L2 Cervical and lumbar enlargements (plexuses) contain the cell bodies of the many spinal nerves to the limbs Cauda Equina The Nerve roots of lumbar and sacral Spinal nerves. Ascending and descending white matter tracts carry information to/away from brain
conductive segment of a neuron (3)
Extends the full length of the axon - voltage-gated Na+ channel and Voltage-gated K+ channel
CN 111: Oculomotor nerve
Eye muscle movement (motor output)
Orbital
Eyes
Which of the following ions have leak channels on the plasma membrane?
K+ Na+
The RMP is chiefly a consequence of the movement of ions across the plasma membrane through ______ (both K+ ____ and Na+ _________).
Leak channels.
Coronal (Frontal) Plane
Lengthwise plane running from side to side, separating the body from anterior to posterior
Inferior
Lower on the body, farther from the head
What are 4 terms related to organs
Lumen, Central and Peripheal, Medullary and Cortical, and Basal and Apical
What can the Thoracic Cavity be subdivided into
Mediastinum and Pleural Cavities
somatic motor division
Motor output that is consciously or voluntarily controlled; effector is skeletal muscle.
CN VI: Abducens Nerve
Motor: eye movement, lateral rectus muscle
What does the Respiratory System permit
Movement of air into and out of the lungs and allows for exchange of respiratory gases (oxygen and carbon dioxide)
Skeletal Muscle Relaxtion
Muscle returns to the resting state through the natural elasticity of the muscle fiber.
Plasma membrane of entire neuron
Na+/K_ pump Na+ leak channel K+ leak channel
CN V: Trigeminal Nerve
Name the cranial nerve (CN) that is responsible for the muscles of mastication and facial sensation.
peripheral nervous system
Nerves and ganglia
primary somatosensory cortex
Receives and interprets somatic information from receptors for touch, proprioception, and pain.
Organization of the Nervous System
Receptor -> Sensory NS -> CNS -> Motor NS -> Effector
Endocrine and Nervous System
Respond to changes in the environment and body.
Reproductive System
Responsible for reproduction and development
What does the Lymphatic System do
Responsible for returning materials from the tissue spaces back to the blood and plays a role in the immune system
Two directional terms are often used to describe relative position of brain anatomy. Anterior is synonymous with ______
Rostral meaning "toward the nose"
condyle
Rounded process that usually articulates with another bone
What are the 3 Main Body Planes
Sagittal, Coronal (Frontal), and Transverse (Horizontal)
CN V11: Facial Nerve
Sensory Function: Taste Somatic Motor Function: muscles for facial expression, digastric (posterior belly), stylohyoid, stapedius Parasympathetic motor function: Increases secretion from lacriminal gland of eye, submandibular and sublingual salivary glands.
somatic sensory division (sensory NS)
Sensory input that conciously perceived from receptors (e.g., eyes, ears, and skin)
visceral sensory division (sensory NS)
Sensory input that is not consciously perceived from receptors of blood vessels and internal organs (e.g., heart)
CN X: Vagus Nerve
Sensory: throat, thoracic and abdominal viscera Motor: vocalization, swallowing, and autonomic control of viscera
lateral sulcus
Separates temporal lobe from parietal and frontal lobes
Acromial
Shoulder
Cranial
Skull
Plantar
Sole of Foot
CN 1V: Trochlear Nerve
Somatic Motor Function: superior oblique extrinsic eye muscle
CN X1: Accessory
Somatic motor function: most pharyngeal muscles; all laryngeal muscles
Astrocyte function and location
Starlike shape due to projections from their surface.. Have contact with both neurons and capillaries (smallest blood vessels). Most abundant glial cells in the CNS and constitute 90% of the nervous tissue/ - Help form the blood-brain barrier - Regulate interstitial fluid composition. - Form structural support - Assist neuronal development - Occupy the space of dying neurons
Extension
Straightening a body part
Initial segment "trigger zone"
Summation of EPSPs and IPSPs includes both spatial summation of two or more presynaptic neurons and temporal summation of one presynaptic neuron; rapidly releasing neurotransmitter determines if threshold (-55 mV) is reached.
Initial segment
Summation of graded potentials; initiation of action potential
Most researchers believe that MS results from a combination of genetic and environmental factors. One peculiar observation regarding environment is the fact that the incidence increases as one gets further from the equator.
TRUE
Insula
Taste (gustatory) area
What can the Abdominopelvic be subdivided into
The Abdominal and Pelvic Cavities
Extensibility of Muscle Tissue
ability to extend/ lengthen of muscle tissue without damage
Elasticity of muscle tissue
ability to return to original shape after being stretched
Contractile Protein
actin and myosin -generate force during contraction
Thin filaments are composed of
actin, tropomyosin, troponin
Transmissive segment
action potential causes release of neurotransmitter; axon terminal
Tarsal
ankle
One of the horns of Gray Matter ___ contains cell bodies of somatic motor neurons.
anterior
The motor neurons conduct action potentials through the anterior root of the spinal cord.
anterior root
The _______ pathway transmits stimuli related to crude touch, pressure, pain, and temperature to the cerebrum (parietal lobe).
anterolateral
sensory nerves
The nerves that carry sensations of touch, taste, heat, cold, pain, and other modalities from the body to the central nervous system.
symptoms of multiple sclerosis come and go. This is because
The oligodendrocytes are constantly renewing the myelin sheaths, so they are able to temporarily repair some of the damage
Define the term homeostasis.
The process of maintaining a constant internal environment (temperature, water content, available energy, available oxygen and concentration of wastes in the blood).
General Functions of Spinal Cord and Spinal Nerves
The spinal cord and spinal nerves serve as a pathway for sensory and motor nerve signals and are responsible for reflexes.
membrane potential
The voltage across a cell's plasma membrane.
Spinal Nerve Identification and Gross Anatomy
There are 31 pairs of spinal nerves: - 8 pairs of cervical nerves. - 12 pairs of thoracic nerves. - 5 pairs of lumbar nerves. - 5 pairs of sacral nerves. - 1 pair of coccygeal nerves.
The opening of either chemically gated K+ channels gated CI- channels (which allows negatively charged chloride ions [CI-] to enter the neuron) cause the inside of the neuron to become more negative (-70 mV to -71 mV)
This change in MP in the negative direction is called hyperpolarization.
The direction of change (whether the membrane potential becomes more positive or more negative) is dependent upon the type of chemically gated channel that opens. Example, the opening of chemically gated cation channels allows more Na+ (positively charged ion) to enter the neuron (thank K+ to exit), causing the inside of the neuron to become more positive (-70 mV to -69 mV)
This change in MP in the positive direction is called depolarization.
What can the Ventral Cavity (anterior) be subdivided into
Thoracic and Abdominopelvic Cavities
epithelial tissue
Tissue that covers outside of the body and lines organs and cavities and insides.
nervous tissue function
Transmit electrical signals from sensory receptors and to effectors (muscles and glands) which control their activity
What does the Cardiovascular do
Transport materials throughout the body through a series of closed vessels
Motor pathways use at least two motor neurons: one or more upper neurons and a lower motor neuron.
Upper motor neuron: cell body located in cerebral cortex or a brainstem nucleus. Lower motor neuron: cell body located in anterior horn or a brainstem nucleus.
Action potential arriving at the presynaptic terminal cause _____ -gated calcium channels to open
Voltage
transmissive segment (synaptic knobs)
Voltage-gated Ca2+ channels and Ca2+ pumps -signal is transmitted to another cell -arriving action potential causes release of a neurotransmitter that will have an excitatory or inhibitory effect on a neuron, muscle, or gland
Medullary
Inner region of organ
CN X11 hypoglossal
Intrinsic and extrinsic tongue muscles
___ matter is peripherally located and composed of myelinated axons.
White matter
Respiratory, Digestive, and Urinary System
Work together for processing, regulation, and maintenance in the body
Cardiovascular and Lymphatic System
Work together for transportation and defense in the body
Skeletal and Muscular System
Works together to provide support and produce body movements
anterior median fissure
a groove along the anterior midline of the spinal cord that incompletely divides it into symmetrical halves
posterior median sulcus
a shallow vertical groove dividing the spinal cord throughout its whole length in the midline posteriorly.
Sarcomere
a structural unit of a myofibril in striated muscle, consisting of a dark band and the nearer half of each adjacent pale band. -Contractile unit of muscle fiber
Popliteal
area behind the knee
Endomysium
areolar onnective tissue surrounding a muscle fiber -more delicate coverings function to electrically insulate the muscle fiberStr
Lateral
away from the midline
Distal
away from the point of attachment
anterior horn of gray matter
cell bodies of somatic motor neurons
perikaryon or soma
cell body of a neuron
Neuron Structure
cell body, dendrites, axon
Neuroglia
cells that support and protect neurons
the fourth ventricle merges with the ____ in the spinal cord.
central canal
Mesencephalon (midbrain)
cerebral aqueduct
Neurotransmitters
chemical messengers that cross the synaptic gaps between neurons.
Thoracic
chest or thorax
The voltage-gated Na+ channels ____ when the cell reaches +30mV.
close
the somatic sensory division detects stimuli that are ___ detected.
consciously
frontal lobes function
control skilled voluntary movements of limbs and trunk coordinate muscles involved in speech control voluntary movements of eyes and eyelids concentration, problem-solving, and planning
Wernicke's area
controls language reception - a brain area involved in language comprehension and expression; usually in the left temporal lobe
frontal eye field
controls voluntary movement of the eyes
Response to a withdrawal reflex; causes extension of the opposite limb
crossed-extensor reflex
Perimysium
dense irregular connective tissue surrounding a fascicle (bundle of muscle fibers)
sensory nervous system
detects stimuli and transmits information from receptors to the CNS
monosynaptic reflex
direct communication between sensory and motor neuron (stretch reflex)
Sagittal Plane
divides body into left and right
central sulcus
divides frontal and parietal lobes
The net diffusion of a given ion is dependent upon its ____ ______.
electrochemical gradient
contractility of muscle tissue
enables muscle cells to cause body movement and to perform the other functions of muscles.
An individual axon is wrapped in a connective tissue covering called ___.
endoneurium
CSF is produced by secretion of a fluid from the ___ cells.
ependymal
The ____ space is external to the dura mater and contains adipose connective tissue and blood vessels
epidural
Gross structure of skeletal muscle
epimysium, perimysium, endomysium
The diencephalon is organized into the:
epithalamus, thalamus, and hypothalamus (which are essentially internal structures)
Characteristics of Skeletal Muscle
excitability, conductivity, contractility, elasticity, extensibility
characteristics of neurons
excitability, conductivity, secretion, extreme longevity, amitotic
Postsynaptic potentials that result in the neuron becoming more positive (i.e., depolarized) are more specifically called ____.
excitatory postsynaptic potentials (EPSPs)
deeper grooves are named
fissures
Extracellular fluid (ECF)
fluid outside the cells; includes intravascular and interstitial fluids
Intracellular fluid (ICF)
fluid within the cell; synonym for cellular fluid
Sensory and motor axons are ___.
found in mixed nerves
Interneurons (association neurons)
found in neural pathways in the CNS, connect sensory and motor neurons -most abundant
The ___ ventricle is located between the pons/medulla and the cerebellum
fourth ventricle
Antecubital
front of elbow (anterior)
neurofibril nodes (nodes of Ranvier)
gaps between neurolemmocytes
prevents contracting muscles from applying tensions to tendons
golgi tendon reflex
The folds of brain tissue are called
gyri
Skeletal muscle tissue exhibits a ____ metabolic demand for energy.
high
Foramen (foramina plural)
hole in a bone
Lumen
hollow areas of organs
motor speech area
in the frontal lobe, translates thoughts into speech
The Cerebrum is ____ to the cerebrum
inferior
Postsynaptic potentials the result in the neuron become more negative (i.e., hyperpolarized) are called ______.
inhibitory postsynaptic potentials (IPSPs)
motor nervous system
initiates and transmits information from the CNS to effectors
polysnaptic reflex
interneuron facilitates sensory-motor communication (ex: withdrawal reflex)
Conductivity
involves sending an electrical change down the length of the plasma membrane as voltage-gated channels open sequentially during an action potential.
The diffusion of ____ into the cell or out of the cell causes a change in membrane potential
ions
One of the horns of Gray Matter ___ contains cell bodies of autonomic motor neurons.
lateral
When K+ diffuses out of a cell, the cell becomes ____ depolarized.
less
Neurotransmitter combine with their receptor sites and cause ___-gated ion channels to open
ligand
arachnoid mater (meninges / spinal cord)
middle layer
When Na+ diffuses into the cell, the cell becomes more ___ depolarized
more
A motor neuron conducts action potentials from the spinal cord to an effector organ.
motor neuron
autonomic motor system
motor output that is not consciously or is involuntarily controlled; effectors are cardiac muscle, smooth muscle, and glands.
Many dendrites and a single axon
multipolar neuron
stretch reflex
muscle contraction in response to stretching within the muscle
muscle fibers aka
myofibers
Umbilical
navel
Cervical
neck region (C1 to C7)
K+ diffusing out of the cell has a _____ feedback effect on the initial polarization.
negative
Although there's K+ inside the ICF it's ______.
negatively charged.
Calcium ions diffuse into the cell and cause synaptic vesicles to release
neurotransmitters
examples of neurotransmitters
norepinephrine, serotonin, dopamine, acetylcholine
The voltage-gated Na+ channels ___ when the cell membrane reaches threshold level as a result of a stimulus.
open
intercalated Disc
part of the sarcolemma that connects cardiac tissue, and contains gap junctions and desmosomes
premotor cortex function
planning and movement -plans and coordinates learned, skilled motor activities involving skeletal muscles.
Sarcolemma
plasma membrane of a muscle fiber
Na+ diffusing into the cell causes more Na+ gates to open, which is a ____ feedback loop.
positive
One of the horns of Gray Matter ____ contains sensory axons and interneurons.
posterior
The _______ lemniscal pathway transmits stimuli of fine proprioception, discriminitive touch, precise pressure, and proprioception pressure to the cerebrum (parietal lobe)
posterior funiculus-medial
The sensory neurons conduct action potentials through the posterior root of the spinal cord.
posterior root
Neurotransmitters diffuse from the ____ terminal across the synaptic celft
presynaptic
Golgi tendon reflex
produces muscle relaxation and lengthening in response to contraction -polysnaptic reflex
Conductive segment
propagation of action potential
Satellite cell functions
protects and regulates nutrients for cell bodies in ganglia - electrically insulates PNS cell bodies
Thick filaments are composed of
protein myosin
3 structures of a feedback loop/feedback mechanism
receptor, integrating center, and effector
When the neuron is at rest, the membrane potential is more specifically called the ______. The ____ of a neuron is typically -70 mV, but can range between -40 mV and -90 mV
resting membrane potential (RMP)
For example, this occurs when you step on a sharp object with your left foot and then contract the muscles in your ____ leg to maintain balance as you withdraw from the damaging object.
right
Transverse (Horizontal) Plane
runs horizontally from right to left, dividing the body into superior and inferior parts
motor nerves (efferent)
sends information to muscles to carry out central nervous system commands
CN 1X - Glossopharyngeal
sensory and taste from posterior of tongue, part of the pharynx, visceral from carotid bodies; one pharyngeal muscle (stylopharyngeus); increases secretion from parotid salivary gland
contralateral reflex
sensory impulses enter one side of the spinal cord and motor impulses exit on the opposite side
Functions of the nervous system
sensory input, integration, motor output - collect information, process and evaluate information, initiate response to information
A sensory neuron conducts action potentials from the stimulus site to the spinal cord.
sensory neuron
A stimulus is detected by a ______.
sensory receptor
The two lateral ventricles are separated by a thin membrane partition called the ____.
septum pallucidum
muscle tissue types
skeletal, smooth, cardiac
somatic sensory pathway
skin, muscles, and joints
visceral sensory pathway
small intestines, heart, and urinary bladder
Facet
smooth, nearly flat articular surface
parietal lobe function
somatic sensory processing
The _____ pathway transmit stimuli from proprioceptors to the cerebellum.
spinocerebellar
ipsilateral reflex
stimulus and response are on the same side of the body
the simplest reflex; muscles contract in response to a stretch
stretch reflex
The ____ space lies between the ____ mater and pia mater and contains cerebrospinal fluid (CSF)
subarachnoid
A potential ______ spaces lies between the dura mater and arachnoid mater
subdural
Shallow depressions between the folds of the brain are called
sulci
functions of the osseous tissue and bone structure
support, protection, storage, blood cell production, and leverage
apical surface
surface of an epithelial cell that faces away from the basement membrane
prefrontal cortex
the frontmost portion of the frontal lobes, especially prominent in humans; important for attention/concentration, working memory, decision making, appropriate social behavior, and personality
Synapse
the junction between the axon tip of the sending neuron and the dendrite or cell body of the receiving neuron
The brainstem has 3 regions:
the midbrain, pons, and medulla oblongata
Articular Surface
the point where two bones come together
primary motor cortex
the region of the posterior frontal lobe that contains neurons that control movements of skeletal muscles
basal surface
the surface near the base or interior of a structure; nearest the lower side or bottom of a structure; near basement membrane
dura mater (meninges / spinal cord)
thick, outermost layer of the meninges surrounding and protecting the brain and spinal cord
Femoral
thigh
Superior
toward the head
Medial
toward the midline
The role of neurotransmitters is to...
transmit an impulse across a synapse to another cell.
one process with two branches; one extending to the CNS, one extending to the periphery
unipolar neuron
Motor pathways use ___ and ___ motor neurons
upper and lower
Brachial
upper arm
The cavities within the brain are called ___.
ventricles
CN11 Optic
vision
occipital lobe function
visual processing
initial segment (axon hillock)
voltage-gated Na+ channels and voltage-gated K+ channels
Removes a body part from a painful stimulus
withdrawal reflex
Carpal
wrist
Pumps move substances against a concentration gradient, a process that requires energy. Channels instead provide the means to move a substance with a concentration gradient. Neurons contain the following major types of channels:
• Channels that are always open, allowing continuous diffusion of a specific ion from a region of high concentration to a region of low concentration are leak channels.
Flexion
decreases the angle of the joint and reduces the distance between the two bones
Pia mater (meninges / spinal cord)
(innermost layer) internal layer, clings to the surface of the brain
Excitabilty
(responsiveness, irritability); the ability of muscle tissue to recieve and respond to a stimulus, that is any change in the environment either inside or outside the body
Cortex
(superficial layer of gray matter) outermost covering of the brain consisting of densely packed neurons, responsible for higher thought processes and interpretation of sensory input
withdrawal and crossed extensor reflex
(withdrawal) Painful stimulus triggers withdrawal reflex, then afferent neurons send signals to efferent neurons controlling muscles on the opposite side to compensate. -Crossed-extensor reflex occurs in response to the withdrawal reflex, by stimulating the extensor muscles in the opposite limb and thereby ensuring the opposite limb supports the body's weight. -polysnaptic reflex
Pumps move substances against a concentration gradient, a process that requires energy. Channels instead provide the means to move a substance with a concentration gradient. Neurons contain the following major types of channels:
* Channels that are normally closed that open in response to the binding of a neurotransmitter are chemically gated channels. When open, they allow a specific ion to diffuse across the plasma membrane.
Innervation of Skeletal Muscle Fibers
- A motor unit consists of a motor neuron and all the muscle fibers it innervates and controls. - The neuromuscular junction is the location where a motor neuron innervates a muscle fiber.
Microscopic Anatomy of Skeletal Muscle
- A skeletal muscle fiber is multinucleated cell. - The sarcolemma, T-tubules and sarcoplasmic reticulum have specialized membrane pumps and channels that participate in muscle excitability, conductivity, and initiation of muscle contraction. - Skeletal muscle fibers are filled with myofibrils that house thick and thin protein filaments, which are composed of myosin and actin protein, respectively. - Myofilaments are arranged in repeating, functional units called sarcomeres. - Other specialized structural and functional proteins of muscle tissue fibers include connectins (titin) and dystrophin. - Numerous mitochondria, glycogen stores, myoglobin, and creatine phosphate all function to help meet the high energy demands of skeletal muscle tissue.
sensory pathways
- Nerve signals ascend to the brain in sensory pathways. - posterior pathways travel in the posterior and lateral funiculi of the spinal cord.
Motor Pathways
- Nerve signals descend from the brain in motor pathways. - Motor pathways travel through the anterior and lateral funiculi of spinal cord.
Microglial cells (CNS)
- Phagocytic cell that moves through the CNS. - Protects the CNS by engulfing infectious agents and other potentially harmful substances.
Gross Anatomy of Skeletal Muscle
- Skeletal muscle is ensheathed by 3 connective tissue layers: an epimysium, a perimysium, and endomysium. - Tendons or aponeuroses are extensions of these three layers of connective tissue that attach muscle ends to other structures. - Skeletal muscle is highly vascularized, and it is innervated by motor neurons that exert voluntary control of muscle.
Sensory pathways to the cerebrum use up to three neurons: a primary, secondary, and a tertiary neuron.
- Tertiary neuron: cell body located in thalamus. - Secondary neuron: cell body located in posterior horn or a brainstem nucleus. - Primary neuron: cell body located in posterior root ganglion.
Oligondendrocytes
- The cells that make the myelin sheath in the CNS - Allows faster action potential propagation along axons in the CNS.
Supplying Energy for Skeletal Muscle Metabolism
- The major means to supply energy to skeletal muscle are limited amounts of ATP, phosphate transfer, glycolysis, and aerobic cellular respiration. - The duration and intensity of activity determine the primary means of supplying ATP.
receptive segment of neuron
- dendrites and cell body - chemically gated chennels (cation channels, K+ channels, and CI- channels)
Ependymal cells (CNS)
- line the cavities of the brain (ventricles) and spinal cord (central canal) - Assists in production and circulationof cerebrospinal fluid (CSF)
Neurolemmocytes (Schwann cells)
- myelinates and insulates axons in the PNS - Allows for faster action potential propagation along an axon.
Cervical
- nerves innervate muscles of the neck -C1 to C8 -has neurons that innervate the upper limbs
Graded potentials are established in the _____ segment by the opening of _____ channels.
- receptive segment - chemically gated channels: cation channels, chemically gated K+, chemically gated CI-
What is the Urinary System responsible for
- removing: metabolic wastes and chemicals in excess (including drugs) - reabsorbing water and nutrients
The meninges include:
- the pia mater - arachnoid mater - dura mater
Protection and support of the spinal cord includes:
- the vertebral column - meninges - a cerebrospinal fluid (CSF)
Which of the following are true of neurolemmocytes?
- they create the myelin sheath in the PNS - They are also called Schwann cells
meatus or canal
A passageway through the substance of a bone
positive feedback loop
A response that intensifies a change in the body Then, change abruptly ends EX. Childbirth
Rule of Nines
A system that assigns percentages to sections of the body, allowing calculation of the amount of skin surface involved in the burn area. 9% on each arm perineum area 1% 18% on each lower lumb front and back upper areas are 18% each
Conductive Segment
Action Potential: Depolarization: Opening of voltage-gated Na+ channels in response to reaching threshold. Na+ moves into axon. Repolarization: Opening of voltage-gated K+ channels that immediately follows depolarization to reestablish RMP. K+ moves out of axon. Nerve Signal: Propagation of Action Potential: Action potential are propagated at neurofibril nodes (in myelinated axons) and are propagated from the initial segment to the synaptic knob.
Axillary
Armpit
Transmissive Segment: Release of Neurotransmitter
Arrival of a nerve signal at the synaptic knob triggers the opening of voltage-gated Ca2+ channels. Ca2+ enters the synaptic knob, causing the subsequent release of neurotransmitter from synaptic vesicles by exocytosis.
Skeletal Muscle Fibers at Rest
At rest, skeletal muscle fibers have an RMP of -90 mV with more Na+ outside the cell and more K+ inside the cell.
Patellar
Front of Knee
What is the Nervous System responsible for
Generating and interpreting nerve impulses, occurs rapidly and lasts a short period of time
_____ matter is centrally located and composed of neuron cell bodies, dendrites, unmyelinated axons, and glial cells.
Gray matter
Inguinal
Groin
CN V111 - Vestibulocochlear
Hearing (cochlear branch); equilibrium (vestibular branch)
lateral horn of gray matter
I Function: contain cell bodies of motor neurons to supply muscles and glands
CN1
Olfactory (smell)
Cortical
Outer region or layer of an organ
Palmar
Palm of hand
Graded potentials that occur in the postsynaptic neurons are specifically called ____.
Postsynaptic potentials
Integumentary System
Protects the body, keeps harmful material out, regulates body temperature, senses and responds to the environment, and creates important chemicals
Spinal Cord Gross Anatomy
The adult spinal cord traverses the vertebral canal and typically ends at the level of the L1 vertebra.
When is a body in anatomical position
The body is erect, or standing, posture with arms at the sides and palms foreward
Receptive Segment
binding of neurotransmitter released from presynaptic neuron; production of graded potentials
One dendrite and one axon
bipolar neuron
there is ___ brain barrier that prevents harmful materials in the brain
blood
Osseous
bone tissue
location of osseous tissue
bones
central nervous system
brain and spinal cord
Mammary
breast
Gluteal
buttock
Pumps move substances against a concentration gradient, a process that requires energy. Channels instead provide the means to move a substance with a concentration gradient. Neurons contain the following major types of channels:
• Channels that are always open, allowing continuous diffusion of a specific ion from a region of high concentration to a region of low concentration are leak channels. • Channels that are normally closed that open in response to the binding of a neurotransmitter are chemically gated channels. When open, they allow a specific ion to diffuse across the plasma membrane. • Channels that are normally closed, but open in response to changes in electrical charge across the plasma membrane are voltage-gated channels. When open, they allow a specific ion to diffuse across the membrane.
Pumps move substances against a concentration gradient, a process that requires energy. Channels instead provide the means to move a substance with a concentration gradient. Neurons contain the following major types of channels:
• Channels that are normally closed, but open in response to changes in electrical charge across the plasma membrane are voltage-gated channels. When open, they allow a specific ion to diffuse across the membrane.
