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