Bio 201 - Human Anatomy & Physiology I Unit 4
Describe the four types of ion channels and explain how ion channels cause development of the resting membrane potential in neurons Ligand-gated
open in response to binding of specific chemical or ligand to a specific receptor
Describe the four types of ion channels and explain how ion channels cause development of the resting membrane potential in neurons Voltage-gated
open in response to changes in voltage across membrane
Describe the four types of ion channels and explain how ion channels cause development of the resting membrane potential in neurons Mechanically-gated
open or close in response to mechanical stimulation (pressure, stretch, or vibration)
Describe each of the following types of receptors, indicating what sensation it detects and giving an example of where it can be found in the body: photoreceptors
only in eye
Describe a simple stretch reflex
optimal length
Describe the gross anatomy of the spinal nerves Epineurium
outermost layer
Discuss the concept of cerebral lateralization
phenomenon in which many cognitive functions are unequally represented in right and left hemispheres
Describe the location and general function of the cerebellum
posterior and inferior portion of brain heavily involved in planning and coordination of movement (sports or instrument) divided into anterior, posteriorm and flocculondular
Include a description of the meninges and relative spaces that protect the spinal cord dura mater
only one meningeal layer
Describe the types of peripheral nerves and explain the differences between spinal nerves and cranial nerves sensory nerves
only sensory neurons
Briefly describe the three classes of memory (classified by length of time they are stored) Immediate
stored only for a few seconds
Describe the gross anatomy of the spinal nerves Endoneurium
surrounded by its own connective tissue
Describe each of the following types of receptors, indicating what sensation it detects and giving an example of where it can be found in the body: thermoreceptors
temperature change
Describe the functions of each of the horns of gray matter in the spinal cord lateral horn
control of viscera via ANS
Describe the structure and function of each component of the neuron Cell body
- metabolically active - manufactures all proteins needed for whole neuron
Describe the four components that make up the dicephalon Subthalamus
controls movement
List the number of spinal nerves detailing how many pairs are in each category
- 31 pairs of spinal nerve - 8 pairs of cervical nerves - 12 pairs of thoracic nerves - 5 pairs of lumbar and sacral nerves - 1 pair of coccygeal nerves
Describe the functions of cerebrospinal fluid as well as the details of its production, its circulation within the CNS, and its ultimate reabsorption into the bloodstream
- cushions brain and mains constant temperature within cranial cavity -removes waste and increases buoyancy of brain; keeps brain from collapsing under its own weight
Describe the major functions of the nervous system
- directs voluntary movement - regulates respiratory rate, blood pressure body temperature, sleep/wake cycle, blood pH
Describe the ventricles of the brain
- lined with ependymal cell - filled with cerebrospinal fluid - anterior horn, inferior horn, and posterior horn
Describe the structure and function of each component of the neuron Dendrites
- short balanced processes - receives input from other neurons
Explain the physiologic basis of the absolute and refractory periods
1) absolute - when no additional stimulus is able to produce an additional action potential 2) relative - follows immediately after absolute refractory period
Describe the events of chemical synaptic transmission in chronological order
1) an action potential in presynaptic neuron triggers voltage-gated calcium ion channels in axon terminal to open 2) influx of calcium ions causes synaptic vesicles to release neurotransmitter into synaptic cleft by exocytosis 3) neurotransmitter bind to receptors on postsynaptic neuron 4) ion channels open, leading to a local potential and possibly an action potential, if threshold is reached
List the four spinal nerve plexuses
1) cervical plexus 2) brachial plexus 3) lumbar plexus 4) sacral plexus
Compare and contrast myelination in the PNS and CNS
1) neurolemma - found on outer surface 2) number of axons myelinated-oligodendrocytes have multiple processes that can provide myelination for multiple axons for multiple axons (CNS), while a Schwinn cell only provides myelination for one axon (PNS) 3) timing of myelination - early in fetal development (PNS) much later in CNS
List the three ways synaptic transmission is terminated
1) some neurotransmitters diffuse away from synaptic cleft in ecf or can be reabsorbed into a neuron or an astrocyte 2) neurotransmitter can be broken down in synaptic cleft by enzymes 3) some neurotransmitters are reabsorbed into presynaptic neuron by a process called reuptake
Compare and contrast electrical and chemical synapses
1) synaptic vesicles - filled with chemical messengers 2) synaptic cleft - small-ecf filled space 3) neurotransmitter receptors-bind to neurotransmitter
Describe the four major categories of neurotransmitters Amino Acid
3 main types: 1) glutamate - most important 2-3) glycine and gaba - major inhibitory neurotransmitters
Describe the differences between the endocrine system and the nervous system in terms of how they maintain homeostasis
Actions of endocrine systems are typically slow whereas actions of nervous systems are generally immediate
Describe the difference between ascending and descending tracts in the spinal cord
Ascending - carry various kinds of sensory information Descending - transmit motor information from specific regions in brain down spinal cord to specific regions in body Corticospinal - largest descending tract
Explain how axon diameter and myelination affect conduction velocity
Axons with larger diameter have faster conduction speeds because larger axons have a lower resistance to conduction Presence of absence of myelination gives rise to two types of conduction: saltatory and continuous conduction
Identify the areas of the cortex responsible for cognition and language
Broca's - frontal lobe / production of language Wernicke's - temporal lobe / understanding language and linking word with its correct symbolic meaning Aphasia - language deficit
Describe the location and functions of the limbic system
Found only within mammalian brains Involved in memory, learning, emotion, and behavior
Describe the five lobes of the cerebral cortex, and explain how motor and sensory functions are distributed among the lobes
Frontal - most anterior Parietal - posterior to frontal lobe Temporal - hearing, language, memory, and emotions Occipital - vision Insulas - taste and viscera
Describe the role of the hypothalamus and the reticular formation of the medulla in maintaining homeostasis of vital functions
Hypothalamus - closely associated with pituitary gland; reflects close relationship between these vital systems reticular formation - controls functions of many internal organs as well as aspects of behaviors Hypothalamus - regulates body temperature and feeding
Discuss the relationship between a neurotransmitter and its receptor
Most neurotransmitters can have both EPSP and IPSP depending on which postsynaptic neuron receptor they bind classified into four groups based on chemical structure
List the structures of peripheral nervous systems
PNS - consists of all nerves in the body outside the protection of the skull and vertebral column
Describe the structural basis for and the importance of the blood-brain barrier
Protective safeguard; separates CSF and brain ECF from chemicals and disease-causing organisms sometimes found in blood plasma - consists mainly of simple squamous epithelia (cells of blood capillaries, their basal laminae, and astrocytes
Briefly describe the six classes of mechanoreceptors and two types of thermoreceptors: merkel cell fibers
detect discriminative touch stimuli (skin of hands)
Briefly describe the six classes of mechanoreceptors and two types of thermoreceptors: lamellated corpuscles
detect high frequency vibratory and deep pressure stimuli
Identify and describe the cranial meninges and explain their functional relationship to the brain Epidural space
only allows passage of blood vessels
Briefly describe the three classes of memory (classified by length of time they are stored) Short term
stored for several minutes
Describe the types of peripheral nerves and explain the differences between spinal nerves and cranial nerves mixed nerves
contains both sensory and motor neurons
Identify and describe the cranial meninges and explain their functional relationship to the brain Subarachnoid space
contains major blood vessels of brain
Explain the major differences between the three functional divisions of the nervous system Motor
actions performed in response to integration 1) somatic - consists of neurons that transmit signals to skeletal - voluntary control 2) somatic - consists of neurons that carry signals to thoracic and abdominal viscera - regulates the secretion of certain glands, contraction of smooth muscle, and contraction of cardiac muscle in the heart - involuntary control
Describe the four types of ion channels and explain how ion channels cause the development of the resting membrane potential in neurons Leak channels
always opens and continuously allow ions to flow down concentrations gradients between cytosol and ECF
Explain the major differences between the three functional divisions of the nervous system Integrative
analyze and interpret - 99% of integrated sensory info is disregarded as unimportant
Include a description of the meninges and relative spaces that protect the spinal cord pia mater
anchors spinal cord
Describe the four major categories of neurotransmitters Biogenic
are a class of five neurotransmitters synthesized from amino acids a) norepinephrine b) epinephrine c) dopamine d) serotonin e) histamine
Describe the structure and function of each component of the neuron Axon
axon - each neuron has only one axon or nerve fiber that can generate and conduct an action potential may have the following distinct regions: axon hillock - a region where axon originates from the cell body axon collaterals - branches that extend from the main axon telodendria - smaller branches that arise from axon and axon collaterals near where these extensions end axon terminals (Synaptic bulbs) - arise from telodendria axolemma - plasma membrane that surrounds axon and its cytoplasm or axoplasm
Describe a crossed-extension reflex
balance and postural support
Include a description of the meninges and relative spaces that protect the spinal cord arachnoid
base of spinal cord
List the structures of the central nervous systems
brain and spinal cord Cranial nerves - 12 pairs of nerves traveling back to or from brain Spinal nerves - 31 pairs of nerves traveling back back to or from spinal cord
Describe the structure and function of each type of neuron and explain how structure supports the function Motor
carry information away from cell body in CNS to muscles and glands mostly multipolar
Describe the structure and function of each type of neuron and explain how structure supports the function Sensory
carry information toward CNS
Discuss the structure and function of the four types of CNS neuroglial cells and the two types of PNS neuroglial cells. Be sure to relate the structure of each to its function Ependymal
ciliated cells that line hollow spaces found within CNS function to manufacture and circulate cerebrospinal fluid
Define and describe exteroceptors
close to body's surface
Describe the four components that make up the dicephalon Hypothalamus
collection of nuclei anterior and inferior to larger thalamus - regulation of autonomic nervous system, sleep/wake cycle, thirst and hunger, and body temperature
Describe the myelin sheath
composed of repeating layers of plasma membrane of a Schwinn cell or an oligodendrocyte
Describe the composition and function of the spinal cord
composed primarily of nervous tissue - relay station-brain can interact with body below head and neck - processing station - spinal reflex do not require higher level processing
Describe the gross anatomy of the spinal nerves Perineurium
connective tissues
Describe the location and general function of the brainstem
connects brain to spinal cord - basic involuntary homeostasis functions - control of certain reflexes - monitoring movement - integrating and relaying information to other parts of nervous system
Identify and describe the cranial meninges and explain their functional relationship to the brain Pia mater
deepest meningeal layer
Describe each of the following types of receptors, indicating what sensation it detects and giving an example of where it can be found in the body: chemoreceptors
depolarize in response to binding to specific chemicals
Describe each of the following types of receptors, indicating what sensation it detects and giving an example of where it can be found in the body: nociceptors
depolarize in response to noxious stimuli (pain receptors)
Briefly describe the six classes of mechanoreceptors and two types of thermoreceptors: tactile corpuscles
dermal papillae
Describe the concept of dermatomes, and explain why they are clinically significant in terms of referred pain
dermatomes - skin divided into different segments based on spiral nerves referred pain is generally located along a dermatome for a particular nerve
Briefly describe the six classes of mechanoreceptors and two types of thermoreceptors: ruffini endings
dermis, hypodermis, and ligaments
Describe each of the following types of receptors, indicating what sensation it detects and giving an example of where it can be found in the body: mechanoreceptors
encapsulated interoceptors or exteroceptors found in musculoskeletal system, skin, etc.
Describe the function of the cerebrum and its overall structure
enlarged superior portion of brain divided into 5 lobes - Frontal lobe - Parietal lobe - Temporal love - Occipital lobe - Insula
Define neuron
excitable cell type responsible for sending and receiving signals in form of action potential
Define each of the two types of memory and provide examples Declarative
fact (phone number)
Define and describe interoceptors
found within body's interior
Define node of Ranvier
gap between adjacent neuroglia
Explain the major differences between the three functional divisions of the nervous system Sensory
gather information about internal and external environments of the body 1) somatic - consists of neurons that carry signals from skeletal muscles, bones, joints, and skin. Also transmits signals from organs of vision, hearing, taste, smell, and balance (special sensory division) 2) visceral - consists of neurons that transmit signals from viscera (organs) such as heart, lungs, stomach, kidneys, and urinary bladder
Describe the four major categories of neurotransmitters Neuropeptides
group of neurotransmitters that have a wide variety of functions within nervous system - must be synthesized in cell body and transported to axon - substance p-pain and temperature - opioids - elicit pain relief and are nervous system depressants - neuropeptide y-feeding behaviors
Briefly describe the six classes of mechanoreceptors and two types of thermoreceptors: hair follicle receptors
hair to land
Describe the structure and function of each type of neuron and explain how structure supports the function Pseudounipolar
have only one fused axon that extends from the cell body and divides into processes: one process carries sensory information from sensory receptors to the cell body and the other process carries sensory information from the cell body to the spinal cord sensory neurons that carry information related to pain, touch and pressure
Discuss the structure and function of the four types of CNS neuroglial cells and the two types of PNS neuroglial cells. Be sure to relate the structure of each to its function Oligodendrocytes
have radiating processes with flattered sacs that wrap around axons of nearby neurons to form myelin sheath
Describe the gross anatomy of the spinal nerves Posterior root ganglion
houses cell bodies
Identify and describe the cranial meninges and explain their functional relationship to the brain Subdural space
houses veins that drain blood from brain
Describe the types of peripheral nerves and explain the differences between spinal nerves and cranial nerves cranial nerves
in head and neck
Define and describe proprioceptors in terms of the general location of each in the body and the origin of the stimuli that each receives
in musculoskeletal system
Describe the reticular formation
one of the most complex regions of the brain - collection of over 100 nuclei in central core of three brainstem subdivisions - output is sent throughout entire brain and spinal cord
Describe the functions of each of the horns of gray matter in the spinal cord anterior horn
involved in somatic motor functions (skeletal muscle contraction)
Define ion channel
ions cannot diffuse through lipid component of plasma membrane
Discuss the structure and function of the four types of CNS neuroglial cells and the two types of PNS neuroglial cells. Be sure to relate the structure of each to its function Astrocytes
large star-shaped cells who many processes terminate in structures called end-feet a) anchor b) transport nutrients and gases c) assist in formation of blood-brain barrier - impenetrable d) repair damage
Describe the location and general function of the diencephalon
located at the center of the brain responsible for - processing, integrating, and relaying info to different parts of the brain - homeostatic functions - regulation of movement - biological rhythms
Describe the four components that make up the dicephalon Thalamus
main entry route of sensory data into cerebral cortex
Describe resting membrane potential
membrane potential becomes more negative until it reaches resting membrane potential resting membrane potential - voltage present when a cell is at rest - typical neuron has a resting membrane potential of -70mV 1) Ion concentration gradients favor diffusion of potassium ions out of cell and sodium ions into cells 2) cytosol loses more positive charges that it gains
Identify the cranial nerves by name and number, classify each as sensory, motor, or mixed and describe the specific functions of each pair of cranial nerves Facial (VII)
mixed (sensory & motor)
Identify the cranial nerves by name and number, classify each as sensory, motor, or mixed and describe the specific functions of each pair of cranial nerves Glossopharyngeal (IX)
mixed (sensory & motor)
Identify the cranial nerves by name and number, classify each as sensory, motor, or mixed and describe the specific functions of each pair of cranial nerves Trigeminal (V)
mixed (sensory & motor)
Identify the cranial nerves by name and number, classify each as sensory, motor, or mixed and describe the specific functions of each pair of cranial nerves Vagus (X)
mixed (sensory & motor)
Interpret a graph showing the voltage-versus-time relationship of an action potential, and relate the terms, depolarize, repolarize, and hyperpolarize to the events of an action potential Hyperpolarization
more negative a change from -70 to -80 mV
Identify and describe the cranial meninges and explain their functional relationship to the brain Dura mater
most durable
Briefly describe the three subdivisions of the brainstem: Medulla oblongata
most inferior structure of the brainstem
Describe the types of peripheral nerves and explain the differences between spinal nerves and cranial nerves motor nerves
mostly motor neurons
Identify the cranial nerves by name and number, classify each as sensory, motor, or mixed and describe the specific functions of each pair of cranial nerves Abducens (VI)
motor
Identify the cranial nerves by name and number, classify each as sensory, motor, or mixed and describe the specific functions of each pair of cranial nerves Accessory (XI)
motor
Identify the cranial nerves by name and number, classify each as sensory, motor, or mixed and describe the specific functions of each pair of cranial nerves Hypoglossal (XII)
motor
Identify the cranial nerves by name and number, classify each as sensory, motor, or mixed and describe the specific functions of each pair of cranial nerves Oculomotor (III)
motor
Identify the cranial nerves by name and number, classify each as sensory, motor, or mixed and describe the specific functions of each pair of cranial nerves Trochlear (IV)
motor
Describe the gross anatomy of the spinal nerves Anterior root
motor neurons
Briefly describe the six classes of mechanoreceptors and two types of thermoreceptors: proprioceptors
movement & position
Interpret a graph showing the voltage-versus-time relationship of an action potential, and relate the terms, depolarize, repolarize, and hyperpolarize to the events of an action potential Repolarization
potassium ion channels open, allows positively charged potassium ions to flow out of cell more negative
Define each of the two types of memory and provide examples Nondeclarative
procedural or skills (how to enter your phone number)
Describe the functions of each of the horns of gray matter in the spinal cord posterior horn
process incoming somatic and visceral sensory information
Define sensory transduction
process where stimulus is converted into an electrical signal
Describe reflex responses in terms of the major structural and functional components of a reflex are
programmed, automatic responses to stimuli - protective negative feedback loops
Describe a tendon reflex
protect
Briefly describe the three subdivisions of the brainstem: Pons
regulation of movement, breathing, reflexes, and complex functions associated with sleep and arousal
Describe the structure and function of each type of neuron and explain how structure supports the function Interneurons
relay information within CNS between sensory and motor neurons makes up most of neurons in body; multipolar, communicating with many other neurons
Compare and contrast continuous and saltatory conduction
saltatory - occurs in myelinated axons where insulated properties of myelin sheath increase efficiency and speed of signal conduction action potentials only depolarize nodes of Ranvier and "jump over" Continuous - in unmyelinated axons where every section of axolemma from trigger zone to axon terminal must propagate an axon potential slows conduction speed as each successive section of axon must depolarize
Describe the four components that make up the dicephalon Epithalamus
secretes melatonin
Identify the cranial nerves by name and number, classify each as sensory, motor, or mixed and describe the specific functions of each pair of cranial nerves Olfactory (I)
sensory
Identify the cranial nerves by name and number, classify each as sensory, motor, or mixed and describe the specific functions of each pair of cranial nerves Optic (II)
sensory
Explain the differences between the sensory and motor divisions of the peripheral nervous system
sensory - consists of sensory neurons a) somatic sensory division - detects both internal and external stimuli b) visceral sensory division - relays internal information from organs of abdominopelvic and thoracic cavities motor - consists of motor neuron s a) somatic motor divisions - voluntary motor functions b) visceral motor division (ANS) - involuntary motor functions
Describe the gross anatomy of the spinal nerves Posterior root
sensory neurons
Briefly describe the three subdivisions of the brainstem: Midbrain
shortest and most superior brainstem region
Discuss the structure and function of the four types of CNS neuroglial cells and the two types of PNS neuroglial cells. Be sure to relate the structure of each to its function Microglia
small and scarce cells that are activated by injury into wandering phagocytic cells (macrophages) ingest disease-causing microorganisms, dead neurons, and cellular debris
Describe the gross anatomy of the spinal nerves Fascicles
small group of bundled axons
Make a complete comparison between local potentials and action potentials Local
small local changes in potential of a neuron's plasma membrane serves as vital triggers for long-distance action potentials
Define Excitatory Postsynaptic Potential (EPSP)
small local depolarization
Define Inhibitory Postsynaptic Potential (IPSP)
small local hyperpolarization
Describe the four major categories of neurotransmitters Acetylcholine (ACh)
small molecule neurotransmitter widely used by nervous system cholinergic synapses binds to ACh and largely excitatory
Describe the four major categories of neurotransmitters Acetylcholine (ACh)
small molecule neurotransmitter widely used by nervous system nervous
Interpret a graph showing the voltage-versus-time relationship of an action potential, and relate the terms, depolarize, repolarize, and hyperpolarize to the events of an action potential Depolarization
sodium channels open, allowing positively charged sodium ions to flow into cell more positive a charge from -70 to -60 mV
Identify and describe the cranial meninges and explain their functional relationship to the brain Arachnoid mater
some degree of elasticity
Describe the types of peripheral nerves and explain the differences between spinal nerves and cranial nerves spinal nerves
spinal cord
Further discuss the anatomy of a spinal nerve to include the relationships between the root, nerve, ramus, and plexus
spinal nerve - short - both carry somatic motor and sensory information 1) posterior ramus - posterior side 2) anterior ramus - anterior side
Briefly describe the three classes of memory (classified by length of time they are stored) Long-term
stored for days, weeks, or even lifetime
Make a complete comparison between local potentials and action potentials Action
uniforms, rapid depolarization and repolarization of membrane potential only generated in trigger zones
Differentiate between gray matter and white matter in the brain and spinal cord
white - in both brain and spinal cord; consists of myelinated axons brain - inside | spinal cord - outside gray - in both brain and spinal cord; neuron cell bodies, dendrites, and unmyelinated axons
Describe the structure and function of each type of neuron and explain how structure supports the function Multipolar
with a single axon and multiple dendrites, make up over 99% of all neurons
Describe the structure and function of each type of neuron and explain how structure supports the function Bipolar
with one axon and one dendrite and a cell body between them found in eye and olfactory epithelium in nasal cavity
Describe a flexion reflex
withdraw limb from painful stimuli