A&P Test 3 (ch 9 and 11), Test 4 (chapter 12, 13,

1. What prevents Ach from causing continued muscle contraction?

- Acetylcholinesterase - diseases such as Botulism, Myasthenia gravis, Organophosphate insecticides, and nerve gases

structure and function of thick myosin filaments

- Composed of a tail which are two intertwined heavy polypeptide chains and two heads which are two smaller light polypeptide chains. - They form cross-bridges between thick myosin and thin actin filaments during contraction

1. What is muscular dystrophy? What causes the most common and serious form?

- a group of inherited muscle destroying diseases that appear doing childhood - females carry and transmit the abnormal gene which is expressed almost exclusively in males

1. Define neuromuscular junction, synaptic cleft, synaptic vesicle, acetylcholine, motor end plate, and junctional fold.

- a region where a motor unit comes in close contact with a muscle cell -an axon terminal and a muscle fiber are separated by this space -membranous sacs within the axon terminal - neurotransmitter is diffuse across the synaptic cleft -muscle fiber sarcolemma is shaped like a trough -deep folds that contain acetylcholine receptors

1. How do actin and myosin interact to produce muscle contraction?What is this mechanism of muscle contraction called?

- actin and myosin filaments overlap only slightly -> actin filaments slide past myosin filaments and overlap -> Myosin heads form cross-bridges with actin which bind to actin, detach, and bind again -> which then pulls actin filaments toward the center of the sarcomere - this is called the sliding filament model of contraction

list three places in the adult brain where the blood-brain barrier may be missing or reduced.Explain why the BBB is missing or reduced in these areas.

- choroid plexus- capillaries are porous - hypothalamus- lack of BBB allows hypothalamus to sample chemical composition of the blood to maintain homeostasis - vomiting center of brain stem - monitors blood for poisonous substances

List and describe the major fissures and sulci of the cerebral hemispheres.

- longitudinal fissure separates the cerebral hemispheres -transverse cerebral fissure separates the cerebrum and cerebellum -Central sulcus separates frontal lobe from parietal -parietal occipital sulcus separates parietal lobe from occipital lobe -lateral sulcus separates the temporal lobe from frontal and parietal lobe

1. What happens if the frequency (number) of stimuli is increased to a muscle?What is the name of the wave seen on the myogram?What is the result if the muscle stimuli are given so quickly that the muscle does not have any time to relax at all?

- multiple America nerve pulses are delivered in rapid succession and the muscle does not have time to completely relax - muscle twitch - more tension results

1. Describe the basic functions of tropomyosin and troponin.

- rod-shaped proteins that spiral around thin actin filaments and block myosin binding sites on actin - popular proteins or three parts. they bind to actin, bind tropomyosin/helps position tropomyosin on actin, and bind calcium ions

1. Define maximal stimulus and recruitment.

- the new stimulus that produces increase contractile force - multiple motor unit summation that increases in muscle tension or force and occurs with an increase in stimulus intensity

Define neuromuscular junction, synaptic cleft, synaptic vesicle, acetylcholine, motor end plate, and junctional fold

- the region where a motor neuron comes in close contact with a muscle cell - axon terminal and muscle fibers are separated in this space - membranous sacs in the axon terminal - a very important neurotransmitter - muscle fibers sarcolemma is shaped like a trough - contain acetylcholine receptors

An action potential is a brief reversal of membrane potential with a change in voltage from __ mV to __ mV.

-70, 30

describe how an action potential is generated

-An end plate potential is generated at the neuromuscular junction which causes a local depolarization which means it is positive inside the cell and negative outside the cell. -Generation and propagation of an action potential. This depolarizes adjacent membrane areas - Repolarization is when the sarcolemma is restored to its inside initial polarized state which means it's a negative inside and positive outside

The region that makes up most of the total brain mass is the ________________________.List some of the basic functions of this region.

-cerebrum - intelligence, reasoning, sensory perception, thought, memory, judgment, voluntary motor activities, visual and auditory activities, conscious perception of special senses such as vision hearing balance smell and taste

what are T tubules? What is the function of T tubules? How do T tubules relate to terminal cisternae of the sarcoplasmic reticulum?

-extensions of muscle cell sarcoma -conduct electrical nerve impulses deep into muscle fibers and to every sacomere - face form triads with two pair terminal cisternae that encircle each sarcomere

1. What actions are necessary for a skeletal muscle to contract?Which one of these actions is the final trigger for muscle contraction?

-must be stimulated by a nerve -must generate an action potential -must propagate an action potential -intracellular calcium levels most prized which is the final trigger for muscle contraction

what actions are necessary for a skeletal muscle to contract? Which of these actions is the final trigger for muscle contraction?

-must be stimulated by a nerve at the neuromuscular junction -must generate an action potential in its sarcolenma -must propagate an action potential along its sarcolemma -intracellular calcium levels must rise = the final trigger for muscle contraction

1. Describe the structure of the thick myosin filaments.What are the functions of the myosin heads?

-myosin is composed of a tail which are two intertwined heavy play with our two hands and two globular heads which are two smaller like polypeptide chains. -functions: form cross-bridges between thick myosin and thin actin filaments during contraction, binding sites for actin, binding sites for ATP, contain ATPase for enzymes

1. Describe the gray and white matter of the cerebral hemispheres.

-the outer cortex is made of gray matter -internal is made of white matter - islands of gray matter within the white matter

Nerve filaments pass through cribriform plate of ethmoid bone

1 - Olfactory Nerves

Sensory for smell

1 - Olfactory Nerves

Tissue Repair

1. Inflammation - release inflammatory chemicals, White blood cells, plasma, clotting proteins and antibodies seep into the injured are, Clotting occurs, & forms a scab, 2. Organization - clot is replaced by granulation tissue, Fibroblasts produce collagen fibers that bridge the gap, Macrophages phagocytize, & Surface epithelial cells multiply and migrate, 3. Regeneration - Scab detaches, Fibrous tissue matures and contracts, & Regenerating epithelium thickens with underlying scar tissue

what are the 4 requirements for skeletal muscle contraction

1. must be stimulated by a nerve at the neuromuscular junction 2. must generate an action potential in its sarcolenma 3. must propagate an action potential in its sarcolenma 4. intracellular Ca levels must rise = the FINAL TRIGGER for muscle contraction

Damage to both of these nerves (right and left) will cause death

10 - Vagus Nerve

Damage to one nerve causes deviation of tongue to side. If both nerves are damaged, the person cannot protrude tongue

10 - Vagus Nerve

Damage to this nerve causes difficulties with speech and swallowing

10 - Vagus Nerve

Damage to this nerve causes hoarseness, loss of voice, difficulty swallowing

10 - Vagus Nerves

Involved in regulating heart rate, respiration, and digestive activity

10 - Vagus Nerves

Motor to muscles of pharynx and larynx for swallowing and voice production

10 - Vagus Nerves

Parasympathetic motor to heart, lungs, abdominal viscera

10 - Vagus Nerves

Damage to this nerve results in difficulty shrugging shoulder

11 - Accessory Nerves

Motor to trapezius and sternocleidomastoid muscles à moves head and neck

11 - Accessory Nerves

Passes through the foramen magnum

11 - Accessory Nerves

Motor to tongue for manipulation of food during chewing and swallowing

12 - Hypoglossal Nerves

Motor to tongue for speech production

12 - Hypoglossal Nerves

Does not relay and synapse in the thalamus

2 - Optic Nerves

Constricts the pupil (parasympathetic)

3 - Oculomotor Nerves

Parasympathetic motor to ciliary muscles for focusing lens

3 - Oculomotor Nerves

Raises the upper eyelid

3 - Oculomotor Nerves

Motor to the inferior oblique eye muscle

3- Oculomotor Nerves

There are _ pairs of spinal nerves. Enlargements in the spinal cord where nerves serve the arms and legs are the ____ enlargement and the _____ enlargement.

31, cervical, lumbar

Sensory from skin of chin and anterior tongue (not taste buds)

4 - Trigeminal Nerves

Motor to the superior oblique muscle of the eye à moves eye down and laterally

4 - Trochlear Nerves

Which ventricle connects to the subarachnoid space and merges with the central canal of the spinal cord?

4th ventricle

Compression of this nerve causes excruciating pain in face (tic douloureux)

5 - Trigeminal Nerves

Has three branches or divisions

5 - Trigeminal Nerves

Main sensory nerve of the face

5 - Trigeminal Nerves

Sensory from teeth

5 - Trigeminal Nerves

Abducts the eyeball

6 - Abducens Nerves

Damage to this nerve causes Bell's palsy

7 - Facial Nerves

Damage to this nerve causes asymmetry of face, inability to close eye, inability to smile, decreased tearing, decreased salivation, decreased taste

7 - Facial Nerves

Has five branches

7 - Facial Nerves

Motor to muscles of mastication / chewing (digastric, masseter, etc)

7 - Facial Nerves

Parasympathetic motor to lacrimal glands

7 - Facial Nerves

Sensory for taste from anterior two-thirds of tongue (taste buds)

7 - Facial Nerves

Damage to this nerve results in loss of balance, dizziness, or deafness

8 - Vestibulocochlear Nerves

Sensory for hearing and equilibrium

8 - Vestibulocochlear Nerves

List the five categories of spinal nerves and the number of nerves in each category.

8 cervica, 12 thoraic, 5 lumbar, 5 sarcral, 1 coccygeal

Damage to this nerve causes decreased salivation, decreased taste in posterior mouth, difficulty swallowing

9 - Glossopharyngeal Nerves

Parasympathetic motor to parotid salivary glands (anterior to ear) à releases saliva

9 - Glossopharyngeal Nerves

Sensory for taste from pharynx and posterior tongue

9 - Glossopharyngeal Nerves

energy sources used during excercise

ATP stored in muscles is used first > ATP is formed from CP and ATP by direct phosphorylation > glycogen stored in muscles by anaerobic glycolysis > ATP is generated by the breakdown of several nutrient Energy Fuels by aerobic respiration

What is meant by excitation-contraction coupling?

Action potential is propagated across the sarcolemma in all directions and down T tubules

Sebaceous (oil) glands

Active at puberty - Sebum is lipids and cell fragments released by cell rupture (holocrine gland

Explain the "all-or-none phenomenon."

An action potential either happens completely or do it not happen at all. Based on whether or not the threshold is reached

How do inborn/intrinsic reflexes differ from learned reflexes? Give some examples.

An inborn/intrinsic reflex is faster predictable motor response to a stimulus; involuntary and unlearned versus a learned reflex which is the result from practice or repetition

What are the two ways in which cartilage grows

Appositional growth - secrete new matrix on the outside of existing cartilage & Interstitial growth - expanding cartilage from within

Which glial cells are located in the CNS?

Astrocytes, ependymal, microglia, and oligodendrocytes are in the CNS

ABCDs of Melanoma

Asymmetry, Border Irregularity, Color, Diameter

Tendon

Attaches muscle to bone

Describe the regeneration of PNS fibers.

Axon and myelin sheath distal to injury degenerate ->macrophages clean up debris distal to injury and release chemicals to stimulate Schwann cells to divide -> Schwann cells release growth factors and cell adhesion molecules -> Schwann cells proliferate and form a regeneration tube which guides axon sprouts -> the axon regenerates and a new myelin sheath forms

What is the normal response to the plantar reflex in a baby less than one year old? What is the normal response in a person greater than one year of age? What is the term for an abnormal response in a person older than one year of age? What does an abnormal response indicate?

Big toe moves up, curling of toes, Babinski sign, primary motor cortex (brain) & corticospinal tract damage

Describe how the structures mentioned in the previous question form CSF.

Blood plasma filters from capillaries to ependymal cell -> ependymal cells modify filtrate by using ion pumps -> cells release CSF to ventricles -> cilia keep CSF in constant motion

List the components of the central nervous system.

Brain, spinal cord

Cardiac muscle tissue (location, function, structure)

Branching striations, uninucleate - Function: involuntary movement of blood - Location: heart

The nervous system is divided into the ____ nervous system composed of the ___ and _____ and the ___ nervous system composed of nerves outside the ___.

CNS, brain, spinal cord, peripheral, CNS

Describe the formation and flow of CSF through the ventricles and into the blood circulation.

CSF is secreted by lateral ventricle choroid plexuses • CSF flows through interventricular foramina into third ventricle • Third ventricle choroid plexus adds more CSF • CSF flows through cerebral aquaduct to fourth ventricle • Fourth ventricle choroid plexus adds more CSF • CSF flows out median aperture and two lateral apertures • CSF fills subarachnoid space (Bathes external surfaces of brain and spinal cord) • CSF is reabsorbed by arachnoid villi into dural venous sinuses • Venous blood of dural venous sinuses drains into the internal jugular veins of the neck

Simple Epithelial Tissue (location, function, structure):

Cells in direct contact with basement membrane which allows molecules to diffuse easily - Functions: absorption, secretion, filtration - Location: air sacs of lungs

Blood tissue (location, function, structure)

Cells suspended in plasma; consists of RBC & WBC - Function: immunity, carry oxygen - Location: Blood vessels

Describe a choroid plexus.

Clusters of capillaries that hang from roof of each ventricle. It is surrounded by pia mater and the ependymal cells are joined by tight junctions

Nervous tissue (location, function, structure)

Composed of neurons and glial cells - Function: Receive and conduct electrical signals - Location: brain, spinal cord

Chromatin (location, function):

Composed of threadlike strands of DNA 30%, histone proteins 60%, and RNA 10% - Form nucleosomes - Coil and condense into chromosomes

Nucleus (location, function):

Contains blueprint for cellular proteins - Most cells are uninucleate - Mature blood cells are anucleate - Comprised of a nuclear envelope/membrane, nucleolus, and chromatin

How do cranial nerves and spinal nerves differ?

Cranial nerves carry impulses to and from the brain while spinal nerves carry impulses to and from spinal cord

Nucleoli (location, function):

Dark staining spherical bodies within nucleus - Synthesizes rRNA

How do dendrites and axons differ in relation to nerve impulse conduction?

Dendrites conduct short distance signals toward the cell body and axons generates and transmits nerve impulses along the its plasma membrane

Smooth ER (location, function):

Does not manufacture proteins - Functions in liver - lipid synthesis, lipid metabolism, cholesterol synthesis, breakdown glycogen, detox - Functions in testes - synthesize testosterone - Functions in intestinal cells - absorption, synthesis, and transport fats - Functions in skeletal & cardiac muscle - storage and release of Ca (sarcoplasmic reticulum)

Name two "feel good" neurotransmitters.

Dopamine, norepinephrine and epinephrine

Periosteum

Double layer membrane; outer is dense irregular connective and inner is osteogenic layer - Secured to underlying bone by Sharpey's/perforating fibers - Function: bone formation & destruction, nutrition & sensation, and anchoring points

Nuclear Envelope (location, function):

Double-membrane, outer layer is continuous with rough ER - Nuclear pores regulate transport of large molecules into & out of nucleus; mRNA

What ae the 2 types of sweat glands

Eccrine & Merocrine

Cytoskeleton (location, function):

Elaborate network of filamentous proteins throughout cytosol - Anchors to membrane proteins - Functions: cell support/shape, cell motility, movement of cell parts, intracellular transport

Which synapse type transmits impulses more rapidly? WHY?

Electrical synapses transmit impulses more rapidly for the release and binding of neurotransmitter

3 major regions of skin

Epidermis - made of stratified squamous epithelium & no blood supply, Dermis - made of fibrous connective tissue, Hypodermis - adipose tissue; not technically a region, thickest on areas w/ lots of wear and tear

Endoplasmic reticulum (location, function):

Extensive network that connects to the nuclear membrane - Helps in synthesis & packaging of proteins and other molecules - 2 regions: rough ER & smooth ER

Explain why myelinated axons conduct action potentials faster than unmyelinated axons.

Fewer channels needed and fewer delays equal faster action potential

Dermis (what type of tissue, what its made of, what accessory structures, what layer)

Fibrous connective tissue - Nerve fibers, blood vessels and lymphatic vessels - Hair follicles + arrector pili, nail roots, sebaceous glands, sweat glands - Papillary and reticular

Microvilli (location, function):

Fingerlike extensions of plasma membrane which increases surface area to allow for increased absorption

Stratified Squamous Epithelium (location, function)

Function: protection - Location: epidermis

Simple Cuboidal Epithelial Tissue (location, function):

Function: secretion & absorption - Location: kidney tubules

Transitional Epithelial (location, function)

Function: stretching - Location: urinary bladder

Adipose Tissue (location, function)

Functions: store energy (fat) - Location: hypodermis

Demyelination of peripheral nerves that usually occurs after a flu-like illness is called _________. Does this disease cause permanent disabilities?

Guillain-Barre syndrome Most people recover all neurologic function w/o medical treatment

Define: gyrus, sulcus, fissure.

Gyrus: elevated ridge Sulcus: shallow groove Fissure: deep groove; helps to separate larger regions of the brain

Bone tissue (location, function, structure)

Hard calcified collagen fibers, osteocytes in lacunae - Function: store calcium - Location: bones

_______ is involved in appetite, wakefulness, learning/memory and is also released from the stomach and inflamed tissues.

Histamine

how do actin and myosin interact to produce muscle contraction? What is the mechanism of muscle contraction called?

In the relaxation stage actin and myosin filaments overlap but in the contraction phase actin filaments slide past myosin filaments. Myosin heads form cross-bridges with actin. Myosin heads bind to actin, detach, and bind again. This pulls actin filaments toward the center of the sarcomere. It is called the sliding filament model of contraction

The main ions involved in the resting membrane potential are ___ and ____

K, Na

The negative interior of the neuron plasma membrane is due to more ___ leaking out and to large anionic ___ being unable to diffuse out of the cell.

K, Na

The plasma membrane of neurons is more permeable to __ than to ____ because there are more __ leakage channels that allow __ to diffuse out

K, Na, K, K

Cells of the epidermis

Keratinocytes - most numerous epidermal cells, arise from stratum basale, produce keratin, increased in areas with high friction, Melanocytes - in stratum basale, produce pigment melanin, Dendritic/Langerhans - arise from bone marrow, help activate immune system by presenting antigens to lymphocytes, Tactile/Merkel - located at epidermal-dermal junction, touch receptors, tackle cell + sensory nerve ending = tactile/Merkle disc

Serous membranes, parietal serosae, visceral serosa

Line ventral body cavities - Line internal body cavities - Cover internal organs

Where are ependymal cells located?

Lining the ventricles of the brain and the central canal of the spinal cord

Cytoplasm (location, function):

Located between plasma membrane and nucleus - Made of cytosol, organelles, and inclusions (chemical substances)

Apocrine sweat glands (abundance, location, secretions, and functions.)

Located in axillary and anogenital areas - In dermis - Secrete by exocytosis (sweat + lipids + proteins) - Function at puberty under androgen (testosterone) influence

Centrosome (location, function):

Located near nucleus - Microtubule organizing center; forms the mitotic spindle during cell division & forms bases of cilia and flagella

What is the Immediate threat of burns

Loss of body fluids, proteins, and electrolytes

What maintains the normal RMP and how does it maintain it?

Maintained by the Na-K pump. Transports 3 Na out of cell and 2 K into cell

What are the 3 pigments that contribute to skin color?

Melanin - only true skin pigment, protects the nuclei of skin cells from UV rays, Carotene - yellow orange pigment, Hemoglobin - red color of oxygenated blood

Peroxisomes (location, function):

Membrane bound sac that contain very strong enzymes (oxidases & catalases) to breakdown and detox harmful substances - Neutralize free radicals; converted to hydrogen peroxide which is converted to water - Energy metabolism; breakdown fatty acids - Liver and kidney cells have many peroxisomes

Lysosome (location, function):

Membrane bound vesicles containing digestive enzymes - Digest harmful substances, autophages, intracellular digestion

Elastic cartilage (location, function, structure)

Mix of elastic and collage - Function: maintain shape but flexible - Location: ear

Eccrine/Merocrine sweat glands (abundance, location, secretions, and functions.)

More numerous than apocrine sweat glands - Abundant on palms of hands, soles of feet, forehead - In dermis - Secrete sweat by exocytosis - Function of sweating

Hyaline cartilage (location, function, structure)

Most abundant, mainly collagen - Function: support, cushion - Location: epiphyseal plates

Why are tumors of neurons rare?

Most mature neurons do not undergo mitosis

Areolar connective tissue (location, function, structure)

Most widely distributed CT - Loose web-like arrangement of all 3 fibers; cells obtain nutrients and release wastes - Function: storage - Location: under epithelial tissue

Cilia (location, function):

Moves materials along surface with brushing/sweeping motion - Moves mucus in trachea or egg through oviduct to uterus

Skeletal muscle tissue (location, function, structure)

Multinucleate cells, striations - Functions: voluntary movement - Location: attached to bone or skin

Name the specific spinal nerve and corresponding plexus that matches the description. Motor to biceps brachii to flex the elbow

Musculocutaneous in brachial plexus

Describe the structural composition of the blood-brain barrier.

Must pass through three layers before they reach brain neurons: Endothelium of capillary walls which are tight junctions between endothelial cells, Continuous basal lamina surrounding capillaries, and the Perivascular feet of astrocytes

The Action Potential - During the resting state prior to an action potential, all gated __ and __ channels are closed. During step 1 or ________, _______ channels open and ___ flows into the axon. During step 2 or ______, channels open and __ flows out of the axon. Because some ___ channels remain open, ___ continues to flow out of the axon, causing a _____. The resting membrane potential is reestablished by ______ pumps.

Na, K, resting stage, leakage, Na, depolarization, K, K, K, hyperpolarization, Na/K

How do neurons and glial cells differ?

Neurons transmit electrical signals while glial cells surround, support, nourish, and protect neurons.

What is a direct-acting neurotransmitter?

Neurotransmitters that bind to channel linked receptor and open ion channels that cause rapid, simples, brief responses

A special rough endoplasmic reticulum in neurons is called _________________________.

Nissl bodies

Short uninsulated gaps between adjacent Schwann cells are called _______ Action potentials can jump from one gap to another, bypassing the myelinated areas, and speeding up transmission of nerve impulses. This type of nerve conduction is called ______ conduction. As a result, transmission of nerve impulses is ______ in myelinated axons than in unmyelinated axons.

Nodes of Ranvier, saltatory, faster

Cells of bone

Osteogenic - stem cell, Osteoblasts - matrix synthesizing responsible for bone growth, Osteocytes - mature bone cell that maintains the bone matrix, Osteoclasts - bone resorbing cell

Microscopic Anatomy of Compact Bone

Osteon - structural unit, Lamellae - collagen fiber running in alternate directions to withstand stress, Central/Haversian canal - contain blood vessels and nerves, Perforating (Volkmann's) canals - Connect blood vessels and nerves to the central canals, Osteocytes become trapped in lacunae, Canaliculi (extensions of osteocyte cytoplasm and gap junctions), Trabeculae - lattice-like arrangement that aligns along lines of stress to resists stress

Dense Regular Connective Tissue (location, function, structure)

Packed collagen fibers ( wavy appearance) - Very few blood vessels, long time to heal - Function: connects muscle to bone (tendon) and connects bone to bone (ligaments)- Location: tendon, ligaments

The 2 layers of the Dermis

Papillary layer: Made of areolar connective tissue, Contains Meissner's corpuscles (touch receptors), Free nerve endings (pain receptors) Reticular layer: Dense irregular connective tissue, Nourished by cutaneous plexus (network of blood vessels), Most collagen fibers run in bundles parallel to skin

Name an example of a stretch reflex.

Patellar (knee-jerk) reflex

Which layer of the meninges clings to the brain?

Pia mater

1. Functionally, synapses may be either _______ or ______. Describe each type of synapse.

Presynaptic, Postsynaptic a. Presynaptic - conducts impulse toward synapse b. Postsynaptic - conducts impulse away from synapse

Flagella (location, function):

Propels the cell forward with undulating/whiplike motion - Found in sperm cells

List six functions of the skin.

Protection • Body temperature regulation • Cutaneous sensation (respond to stimuli outside the body) • Metabolic functions • Blood reservoir • Excretion

1. Multipolar neurons found in the cerebellum are called __________________________ cells.The tree-like pattern of cerebellar white matter is called the _________________________.

Purkinje, Arbor vitae

anerobic glycolysis

R - glucose from glycogen breakdown and blood P - 2 ATP, 2 pyruvate (converted to lactic acid if Oxygen present) energy source - glucose oxygen use - none energy duration - 30-40 seconds

aerobic cellular respiration (reactants, products, energy source, oxygen use, energy duration)

R - glucose from glycogen breakdown and blood P - 32-36 ATP, Carbon dioxide, and water energy source - glycogen, glucose, pyruvic acid, free fatty acids and proteins (last resort) oxygen use - required energy duration - hours

direct phosphorylation of ADP (reactants, products, energy source, oxygen use, energy duration)

R -CP & ADP P - creatine and ATP energy source - CP oxygen use - none energy duration - 15-20 seconds

List the components of a reflex arc.

Receptor -> sensory neuron -> CNS integration center -> motor neuron -> effector

What is gray matter?

Regions of the brain and spinal cord containing cell bodies, dendrites, and unmyelinated axons

What is white matter?

Regions of the brain and spinal cord containing myelinated axons

What is the function of the blood-brain barrier?

Regulates which substances can and cannot enter the interstitial fluid of the brain

Tissue repair (requirements & major steps)

Requires cell division and migration - Regeneration & fibrosis

Reticular Connective Tissue (location, function, structure)

Reticular fibers form networks (stroma) with fibroblasts and lymphocytes - Function: structural framework - Location: lymph nodes

Which glial cells are located in the PNS?

Schwann cells and satellite cells are in the PNS

Describe the process of myelination in the PNS.

Schwann cells surround an axon -> Schwann cell rotates surround the axon wrapping its plasma membrane in layers -> the Schwann cell cytoplasm and nucleus are forced between the membranes -> overlapping layers form myelin sheath and the neurilemma

In the peripheral nervous system _____ cells produce ____ a fatty insulating material that forms a shiny white protective layer around axons

Schwann,, myelin

______ is involved in nausea, mood, and migraine headaches.

Serotonin

Simple Columnar Epithelial Tissue (location, function, structure)

Single layer that may contain goblet cells (secrete mucus) - Functions: absorption & secretion - Location: intestines

Pseudostratified Ciliated Columnar Epithelial Tissue (location, function, structure)

Single layer that varies in height on basement membrane - May contain cilia and goblet cells - Function: mucus secretion & movement - Location: trachea

Mitochondria (location, function):

Site of aerobic cellular respiration & produces ATP - Muscles, kidney, & liver have a lot b/c they use a lot of energy - Contain their own DNA, RNA, & ribosome; reproduce themselves

Ribosomes (location, function):

Site of protein synthesis - Ribosomes read message in mRNA and link amino acids together to form proteins - 2 types = free and bound ribosomes

Cutaneous membranes, mucous membranes, serous membranes

Skin - Line body cavities open to exterior (digestive, respiratory, urogenital) - Line ventral body cavities closed to exterior

Arrector pili

Smooth muscle connected to hair follicle in papillary layer - Contractions force sebum out of hair follicle to skin surface

What is the difference between somatic sensory fibers and visceral sensory fibers?

Somatic sensory fibers transmit impulses from skin, skeletal muscles, bones, and joints to detect touch, pain, taste, smell, vision, sound and body position. Visceral sensory fibers transmit impulses from visceral organs of the thoracic ad abdominal and from blood vessels to detect chemical composition, pH, and stretch.

Golgi apparatus ( function):

Stacked and flattened membranous sacs; cis face is receiving & trans face is shipping - Modifies and packages proteins and lipids made by ER

Functions of hypodermis

Stores fat (energy) - Anchors skin to underlying muscle - Provides cushioning/shock absorber - Provides insulation

Layers of the Epidermis (thick skin)

Stratum basale - single row of stem cells (immature keratinocytes) that divide by mitosis to produce new keratinocytes, Stratum spinosum - keratinocytes appear to have spine bc of prekeratin filaments attached to desmosomes, abundant in melanin granules and epidermal dendritic cells, Stratum granulosum - last living layer; Keratinization begins (Cells flatten, Nuclei and organelles disintegrate, & Accumulate two types of granule), Keratohyaline granules help form keratin and Lamellar granules that contain water-resistant glycolipid that acts as a water barrier, Stratum lucidum -thick skin only; clear, flat, dead keratinocytes unable to receive nutrients, Stratum corneum - 3/4 of epidermal thickness; thick layer of dead flattened, anucleate keratinized plasma membrane sacs. Functions include Protection from abrasion, penetration, water loss, Barrier against biological, chemical, physical assault

_____ reflexes are important in maintaining posture, muscle tone, and balance. These reflexes receive and send impulses on the same side of the body, so they are ______. They are the only ________ reflexes in the human body.

Stretch, ipsilateral, monosynaptic

Which layer of the meninges contains cerebrospinal fluid?

Subarachnoid space

List six important functions of bones.

Support, protection, movement, storage, blood cell formation, triglyceride/energy storage

Rough ER (location, function):

Synthesizes proteins via attached ribosomes, transfer to Golgi apparatus - Products manufactured by the rough ER (proteins, membrane integral proteins, & phospholipids) - Abundant a& prominent in secretory cells, antibody-producing cells, and liver cells

How does an action potential propagate along an axon?

The electrical current in one region of an axon brings the next region of the axon to threshold, initiating another action potential in the region

Why is fat very important in the diets of infants and toddlers?

The myelin/myelin sheaths are made of fat used to surround the axons

1. Describe the divisions of the nervous system.Which division conducts impulses to skeletal muscles?

The nervous system is divided into the central nervous system which contains the brain and spinal cord and the peripheral nervous system which contains neurons outside the central nervous system. The somatic nervous system conducts impulses to skeletal muscles

Why do organophosphate insecticides and nerve gases cause tetanic muscle spasms and overstimulation of autonomic functions (salivation, lacrimation, urination, diarrhea, emesis)?

They block the action of ACh

Why are chemical synapses often called electro-chemical synapses?

They can convert electrical signals to chemical signals that travel across the synapse to the postsynaptic neuron which is converted back into an electrical signal

Why are microglia so important to the CNS?

They can transform into phagocytic macrophages which helps because immune system cells cannot enter CNS

Dense Irregular Connective Tissue (location, function, structure)

Thick and irregular collagen fibers - Function: strength - Location: dermis of skin

Fibrocartilage cartilage (location, function, structure)

Thick collagen fibers - Function: absorb compressive shock - Location: menisci

Why does the nerve axon depend on its cell body?

To recycle and renew its proteins and membrane components.

Smooth muscle tissue (location, function, structure)

Uninucleate, no striations - Functions: involuntary movement of substances - Location: hollow organs

1. What is a motor unit? How does motor unit size relate to muscle size and control?

a motor unit consists of a motor neuron and all the muscle fibers it supplies. large weight-bearing muscles have large motor units as smaller muscles with fine motor control have small motor units

what is a motor unit? How does a motor unit size relate to muscle size and control?

a motor unit consists of a motor neuron plus all the muscle fibers it supplies. large weight-bearing muscles have large motor units and smaller muscles with fine control have small motor units

What is the basic function of the cerebellum?

a. "finetune" skeletal muscle movements, interpret proprioceptive input, adjust posture, and maintain balance

Name the four ventricles of the brain and list the connections between the ventricles.

a. 1st and 2nd 2 c-shaped lateral ventricles in cerebral hemispheres separated by thin membrane called septum pellucidum b. 3rd ventricles which communicates by the interventricular foreman c. 4th ventricle connects to 3rd ventricle by cerebral aqueduct and connects to subarachnoid space by median aperture and the lateral apertures

Name the five regions of spinal nerves.

a. 8 cervical (C1-C8) b. 12 thoracic (T1-T12) c. 5 lumbar (L1-L5) d. 5 sacral (S1-S5) e. 1 coccygeal (Co1)

How does the nervous system distinguish a weak stimulus from a strong stimulus, such as a pin prick from a knife wound?

a. A stronger stimulus generates more nerve impulses

1. What causes rigor mortis?

a. ATP cannot be replenished because it is used up in muscle contraction by calcium flowing into dying cells - Myosin heads cannot detach from actin

Damage to which multimodal association area could result in mental and personality changes including decreased reasoning abilities, decreased attentiveness, lack of initiative and persistence, indecision, poor judgment, recklessness, and decreased inhibitions?

a. Anterior Association Area

List the three parts of the multimodal association areas.

a. Anterior association area (prefrontal cortex) b. Posterior association area c. Limbic association area

1. Knoblike projections of arachnoid mater that protrude through the dura mater are called __________________________________________. These projections allow CSF to be absorbed into the ______________________________.

a. Arachnoid villi / granulations b. dural venous sinus blood

1. What is the only energy source used directly for muscle contraction?List the steps of muscle contraction that require this energy source.

a. Attach myosin heads to actin to form cross-bridges and to detach myosin heads from actin in the sliding filament mechanism b. Transport calcium back into the sarcoplasmic reticulum at end of contraction c. Detach myosin heads from actin and reset/cock myosin heads

List the three structural types of synapses that may occur between two neurons.

a. Axodendritic - synapse and dendrite b. Axosomatic - synapse and soma c. Axoaxonic - synapse and axon

List the three basic components of a chemical synapse.

a. Axon terminal of presynaptic neuron b. synaptic cleft c. neurotransmitter receptors on the postsynaptic membrane

1. What area of the frontal lobe controls muscles involved in speech production and becomes active as a person prepares to speak?

a. Broca's Area

What are the most important functions of the medulla oblongata?

a. Cardiovascular Center, Respiratory center

Which part of the brain initiates skeletal muscle movement?

a. Cerebellum

Describe cerebellar processing for motor activity. (How does the cerebellum fine-tune motor activity to provide smooth, coordinated skeletal muscle movements?)

a. Cerebellum -> superior peduncles -> midbrain -> thalamus -> cerebral cortex

List the four basic regions of the adult brain. List the components in each region.

a. Cerebral hemispheres - cerebrum b. Diencephalon - thalamus, hypothalamus, epithalamus c. Brain stem - midbrain, pons, medulla d. Cerebellum

Which two areas of the adult brain have an outer layer of gray matter in addition to the central gray matter and surrounding white matter? What is this outer layer of gray matter called?

a. Cerebrum and cortex b. Outer cortex

Describe the three types of gated channels.

a. Chemically gated- open when a specific chemical or neurotransmitter binds b. Voltage gated- open and close in response to changes in membrane potential c. Mechanically gated- open and close in response to physical deformation of receptors

Differentiate between the three types of white matter fibers of the cerebrum.

a. Commissures - connect gray matter of the two hemispheres b. Association fibers - connect different parts of the same hemisphere c. Projection fibers - connect cerebral cortex with lower brain or spinal cord

Pons means "bridge." How does this meaning relate to the basic functions of the pons?

a. Connect higher brain centers to the spinal cord, Relay impulses between motor cortex and cerebellum

List three reasons that the brain stem is so important and necessary for life functions.

a. Controls automatic reflexes and functions necessary for survival b. connects higher and lower neural centers (cerebrum, diencephalon, cerebellum to the spinal cord) c. Contains nuclei of 10 of the 12 pairs of cranial nerves

List and explain seven functions of the hypothalamus.

a. Controls the autonomic nervous system - Blood pressure, heart rate, respiration, etc b. Regulates many endocrine system functions c. Center for emotional response d. Regulates body temperature e. Regulates food intake f. Regulates water balance and thirst g. Regulates sleep-wake cycle (influences pineal gland -> melatonin)

Describe two important midbrain nuclei and their functions.

a. Corpora quadrigemina - contain visual reflex centers which coordinate head and eye movements when follow a moving object & auditory relay centers which transfer information from receptors in ear to sensory cortex b. Substantia nigra - prevent unwanted body movements & produce the neurotransmitter dopamine

What are the functions of the meninges?

a. Cover and protect the CNS b. Protect blood vessels and enclose venous sinus c. Contain cerebrospinal fluid d. Form partitions in the skull

What is the decussation of the pyramids and where is it located? What is its significance?

a. Crossover point of the corticospinal tracts b. where medulla joins spinal cord c. Each cerebral hemisphere controls voluntary movements of muscles on the opposite side of the body (contralateral)

Define adaptation of receptors, and give an example.

a. Decrease in sensitivity and nerve impulse generation in the presence of a constant stimulus b. Ex: When turn light on in dark room, you are initially shocked, but photoreceptors adapt

What would happen to the Premotor Cortex were damaged?

a. Decreases in speed, accuracy, agility of typing but does not impair movement; skill could be "relearned"

Neurotransmitters must be removed from the synaptic cleft so the postsynaptic membrane is not continuously stimulated and is able to respond to new signals. List three ways the neurotransmitter may be removed from the synaptic cleft.

a. Degradation of enzymes (acetylcholinesterase) either in the synaptic cleft or the post synaptic membrane b. Reuptake by astrocytes or axon terminal c. Diffusion away from the synaptic cleft and later destroyed

Explain lateralization of cortical function.What is meant by cerebral dominance?What is meant by the quote "Only left-handed people are in their right minds"?

a. Division of labor between hemispheres b. Designates the hemisphere that is dominant for language

What is contained in the dorsal, ventral, and lateral horns of the spinal cord?

a. Dorsal horns - Interneurons receiving somatic & visceral sensory input and sensory fibers b. Ventral horns - Somatic motor neurons c. Lateral horns - Cell bodies of autonomic sympathetic motor neurons

What is contained in the dorsal and ventral roots of the spinal cord?

a. Dorsal root - sensory neurons enter SC b. Motor root - Motor neurons (somatic and autonomic) exit SC

List the three layers of the meninges (from outermost to innermost).List and describe the spaces related to these layers.

a. Dura mater, arachnoid mater, and pia mater b. Epidural space - between skull and dura mater, Subdural space - between dura mater and arachnoid mater, Subarachnoid space - between arachnoid mater & pia mater

Define: exteroceptor, interoceptor, proprioceptor. Give an example or location of each.

a. Exteroceptors - respond to stimuli outside body (on or near body surface). Found in most special sense organs b. Interoceptors (visceroceptors) - respond to stimuli in internal viscera and blood vessels c. Proprioceptors - respond to stretch stimuli in internal structures. Found in skeletal muscles, tendons, joints, ligaments

List the cranial nerves that innervate the salivary glands (two nerves).

a. Facial 7 and Glossopharyngeal 9

List the cranial nerves involved in taste sensation (three nerves).

a. Facial 7, Glossopharyngeal 9, and Vagus 10

Describe the septa that are formed by the inward extensions of the dura mater.

a. Falx cerebri - splits the left and right cerebral hemispheres. It attaches to crista galli of ethmoid bone and to internal occipital crest. b. Falx cerebelli - divides left and right cerebellum c. Tentorium cerebelli - horizontal fold over cerebellum

1. Which area of the frontal lobe controls voluntary eye movements involved in reading, binocular vision, and following a moving object?What muscles are controlled by this area of the cerebral cortex?

a. Frontal Eye Field b.

List four functions of CSF.

a. Gives buoyancy to the brain b. Provide liquid cushion to protect CNS c. Nourishes the brain and removes waste products d. Carries chemical signals from one part of brain to another

List the cranial nerves involved in swallowing (three nerves).

a. Glossopharyngeal 9, Vagus 10, and Hypoglossal 12

Describe the two potentials graded potentials and action potentials, explain how they differ from each other, and explain how they relate to each other.

a. Graded- short distance localized membrane potential change. Spreads depolarizes or hyperpolarizes b. Action- main way to send long distance signals

What is gray matter and white matter? Describe the distribution of gray matter and white matter in the brain and spinal cord.

a. Gray matter - motor neuron cell bodies, interneuron cell bodies, dendrites, unmyelinated axons b. white matter - myelinated axons c. in the spinal cord, the central cavity is surrounded by gray matter and the external is whit matter. In the brain,

Describe the gray matter and white matter distribution in the spinal cord.

a. Gray matter is located in the core b. White matter is located outside

Conditions that obstruct the flow of CSF or prevent the reabsorption of CSF can lead to a build-up of excess CSF called _______________________.Compare the effects of this disorder on the brain of an infant and the brain of an adult.

a. Hydrocephalus b. In a newborn, the head enlarges because skull bones have not fused yet c. In an adult, increasing fluid compresses blood vessels to brain and damages brain tissue

Define ipsilateral, contralateral, monosynaptic, polysynaptic

a. Ipsilateral - receptor and effector organs are on the same side of spinal cord b. Contralateral - sensory impulse cross over in spinal cord to activate effector organs on the opposite side of the body c. Monosynaptic - sensory axon synapse directly on motor neurons, w/ no interneurons involved d. Polysynaptic - sensory axons synapse with one or more interneurons, which then synapse with motor neurons

At what level of the vertebral column does the spinal cord end?

a. L1 or L2 vertebra

Describe the two types of ion channels found in neuron plasma membranes.

a. Leakage / nongated channels - always open b. Gated channels - protein changes shape to open/close channel in response to specific signals

Which multimodal association area provides the emotional impact that makes an event significant and establishes memories of the event?List three components of the MAA.

a. Limbic Association Area b. Anterior association area (prefrontal cortex) • Posterior association area • Limbic association area

1. Describe the reticular formation structurally and functionally.

a. Loosely organized core of gray matter that runs vertically through the brainstem which has motor and sensory components b. Reticular activating system (RAS) • Keeps cerebral cortex conscious, alert, and excitable • Filters out repetitive, familiar, or weak stimuli • Arouses us from sleep • Allows us to sleep under conditions of little or no stimuli

Define: mechanoreceptor, thermoreceptor, photoreceptor, chemoreceptor, nociceptor.

a. Mechanoreceptors - respond to touch, pressure, vibration, stretch, and itch b. Thermoreceptors - respond to temperature changes c. Photoreceptors - respond to light energy (Retina of eye) d. Chemoreceptors - respond to chemicals (Smell, taste, changes in blood chemistry) e. Nociceptors - respond to pain-causing stimuli (Extreme heat or cold, excessive pressure, inflammatory chemicals)

List the components of the brain stem.

a. Mid brain b. Pons c. Medulla oblongata

List the three regions of the brain stem.

a. Midbrain • Pons • Medulla oblongata

What is contained in a spinal nerve?

a. Mixed nerves - contain sensory & motor fibers

Name a monosynaptic reflex. Name a polysynaptic reflex.

a. Monosynaptic -patellar (knee-jerk) reflex b. Polysynaptic - withdrawal reflex

The cerebral cortex contains three "functional" areas. List these three "functional" areas and their basic functions.

a. Motor areas - control voluntary movement • Primary (somatic) motor cortex • Premotor cortex • Broca's area (motor speech area) • Frontal eye field b. Sensory areas - provide conscious awareness of sensation • Primary somatosensory cortex • Somatosensory association cortex • Visual areas • Auditory areas • Olfactory cortex • Gustatory cortex • Visceral sensory area • Vestibular (equilibrium) cortex c. Association areas - integrate and store information • Anterior, posterior, limbic

Describe the three structural classifications of neurons, and give locations of each type.

a. Multipolar - many processes extend from the cell body. All are dendrites except for a single axon. Found in cerebrum, cerebellum (pretty much all over) b. Bipolar - two processes extend from the cell body. One is a fused dendrite and the other is an axon. Found in only retina of eye, olfactory mucosa of nose, and sensory neurons of inner ear c. Unipolar - one process extends from the cell body and forms central and peripheral processes which together comprise an axon. Found in dorsal root ganglia of PNS

What is the neurilemma? Do all myelinated axons have a neurilemma?

a. Neurilemma - when the cytoplasm and nucleus form a thick outermost bulge in the Schwann cell b. no

List some symptoms of hypothalamic dysfunction.

a. Obesity • Body wasting • Sleep disturbances • Dehydration • Emotional imbalances • "Failure to thrive"

List the cranial nerves involved in moving the eyeball (three nerves).

a. Oculomotor 3, Trochlear 4, and Abducens 6

Which sense does not relay through the thalamus? Where does olfaction relay?

a. Olfaction b.

1. What are the basal nuclei? What is the general function of the basal nuclei?

a. Paired masses of gray matter deep within the cerebral white matter b. Help regulate motor output & inhibit antagonistic or unnecessary movements

List three sensations that are perceived in the insula lobe.

a. Perception of taste, perception of visceral sensations, and conscious awareness of balance

Which multimodal association area has a role in recognizing patterns and faces and provides awareness of ourselves and our surroundings in space?What might happen in a person with damage to this MAA?

a. Posterior Association Area b.

Does the blood-brain barrier prevent all substances and molecules from entering the brain?Explain.

a. Prevents metabolic wastes, proteins, toxins, most drugs, potassium ions from entering brain b. Allows nutrients and any lipid-soluble substances to enter

List three functions of the myelin sheath.

a. Protects and insulates axons b. Speeds up transmission of nerve impulses (saltatory conduction) c. Help damage or severed PNS axons regenerate (CNS axon can't regenerate)

What is a multimodal association area? What does a MAS allow us to do?

a. Receive inputs and send outputs from multiple sensory areas b. give meaning to information, store it, compare it, and decide an action

List three levels of neural integration involved in relaying sensory information to the brain.

a. Receptor level - sensory receptors b. Circuit level - ascending pathways c. Perceptual level - neuronal circuits in cerebral cortex

1. How does interaction between the limbic system and the prefrontal cortex affect us?

a. Relationship between our feelings and our thoughts (cognitive)

1. Which system of the brain helps you filter out noises in the cafeteria when you are trying to study?

a. Reticular activating system

When can axon transport be detrimental or harmful?

a. Retrograde axon transport can be harmful to the body because some viruses and bacterial toxins use this to reach the cell body and damage neurons

1. What triggers the sliding filament mechanism?

a. Rise in intracellular calcium

1. What happens when nerve impulses stop stimulating the muscle fiber?

a. Sarcoplasmic reticulum stops releasing calcium b. Already released calcium is pumped back into SR c. Troponin-tropomyosin complexes shift back to original d. Sarcomere stretches back to its original resting length

List four things that protect the brain.

a. Skull/cranium bone b. Meninges (membranes c. Cerebrospinal fluid (watery cushion) d. Blood brain barrier

What are somatic reflexes? What are autonomic/visceral reflexes?

a. Somatic reflexes activate skeletal muscle and mediated by only the spinal cord (spinal reflex) b. Automatic/visceral reflexes activates visceral effectors (cardiac muscle, smooth muscle, glands). They involve brain and spinal cord

What are the conus medullaris, filum terminale, and cauda equina?

a. Spinal cord terminates at L1 - L2 in tapering cone-shaped structure b. attaches to posterior coccyx and anchors spinal cord c. Collection of spinal nerves at inferior end of vertebral canal

How are sensory receptors classified?

a. Stimulus type, Location, and Structural complexity

describe the three paired fiber tracts that connect the cerebellum to the brain stem.

a. Superior cerebellar peduncles - connects cerebellum to midbrain b. Middle cerebellar peduncles - connects pons to cerebellum (voluntary motor activities) c. Inferior cerebellar peduncles - Connect the medulla to the cerebellum (sensory information)

What parts of the body are supplied by spinal nerves?

a. Supply all parts of body except head and part of neck

What is synaptic delay? How does it affect nerve transmission in monosynaptic versus polysynaptic pathways?

a. Synaptic delay - time required for a neurotransmitter to be released, diffuse across the synaptic cleft and bin d to receptors b. Nerve transmission on monosynaptic pathways require only 2-3 neuron while polysynaptic require more neurons due to the fact that they perform higher mental functions

1. What happens after the action potential is propagated across the sarcolemma?

a. T tubules transmit action potential deep into the muscle cell. Triggers the release of calcium ions from terminal cisternae of the sarcoplasmic reticulum

List the five branches of the facial nerve.

a. Temporal, zygomatic, buccal, mandibular, cervical

List the three components of the diencephalon.

a. Thalamus • Hypothalamus • Epithalamus

What conditions are required for a PNS axon/fiber to regenerate?

a. The cell bod must be intact b. Some neurilemma must remain c. Distance between severed ends is not too great

List some other regulatory functions of the medulla.

a. Vomiting • Hiccupping • Swallowing • Coughing • Sneezing • Salivation

1. What role does calcium play in muscle contraction?

a. When calcium levels rise, Calcium binds to troponin, causing troponin to change shape

1. Why does chronic emotional stress sometimes cause visceral or psychosomatic illnesses?

a. b/c the hypothalamus is the main control center for visceral function & emotional response

Cerebrospinal fluid is derived from ____________________. It is formed by structures that hang from the roof of each ventricle of the brain. These structures that form CSF are called __________________________.

a. blood plasma b. choroid plexuses

Where do sensation and perception of stimuli occur?

a. cerebral cortex of the brain

What is the largest commissure that allows that right and left cerebral hemispheres to communicate?

a. corpus callosum

Unencapsulated (free) nerve endings are abundant in which two tissue types?List and define four types of free nerve endings.

a. epithelia and connective tissue b. Thermoreceptors (cold and heat receptors), Nociceptors (sensations perceived as painful), Itch receptors (located in dermis), and Light touch receptors (tactile discs and hair follicle receptors)

List two neurotransmitters that are involved in transmitting pain impulses.List two natural pain inhibitors.

a. glutamate and substance P b. Endorphins (increase when exercise) & Enkephalins (increase during labor)

Inflammation of the meninges is called ___________________________. It may be caused either by ______________________ or __________________________.Which cause is more severe?

a. meningitis b. viral infection, bacterial infection c.Bacterial meningitis

1. Why can odors trigger emotions or be associated with memories?

a. olfactory bulbs and tracts arises from rhinencephalon

What is a reflex? What is the primary function of a reflex?

a. rapid, automatic, involuntary response to stimulus b. It is a survival mechanism which allows a quick response w/o waiting for brain

Action potential conduction in myelinated axons is called ______ conduction. Explain this type of nerve conduction.

a. saltatory b. Action potentials only triggered at Nodes of Ranvier and jump from node to node

Motor areas of the cerebral cortex control _______________________________ movement and are contained in the posterior part of the _____________________________ lobe.List the four motor areas of the cerebral cortex.

a. volutary, frontal b. Primary (somatic) motor cortex • Premotor cortex • Broca's area • Frontal eye field

The periosteal layer and the meningeal layer of the dura mater are fused, but they separate to form a large blood-filled modified vein called the __________. What drains into this "vein"? Where does this vein drain?

a.dural venous sinuses b. a. Drain venous blood from the brain into the internal jugular veins of the neck

Botulism causes muscle weakness, paralysis, and autonomic problems (droopy eyelids and face, difficulty swallowing and speaking, difficulty lifting head, muscular paralysis, diaphragmatic paralysis, decreased salivation, double vision, dilated pupils). The botulinum toxin inhibits the release of the neurotransmitter _______

acetylcholine

Some brain areas of Alzheimer's patients have been found to be deficient in the neurotransmitter _______

acetylcholine

1. The first neurotransmitter identified was _______. What is the primary function of this neurotransmitter?

acetylcholine Released at neuromuscular junction

What parts of the body are supplied by the spinal nerves?

all parts except head and part of neck

1. What causes the striations in skeletal muscle fibers when viewed under the microscope?

alternating light and dark bands in myofibrils

1. A component of the limbic system that recognizes and assesses danger and anger and that elicits the fear or aggression response is the ______________________.

amygdala

The most abundant glial cells in the CNS are _____

astrocytes

Which glial cells help form the blood-brain barrier?

astrocytes

what are the three ways in which ATP is needed for muscles to contract

attach myosin heads to actin to form cross-bridges and detach mice and heads from acting in the sliding filament mechanism transport calcium back into the sarcoplasmic reticulum at the end of contraction deatch myson has from actin and reset myosin heads so relaxation can occur and muscle can be ready for another contraction

characteristics of skeletal muscle

attached to bone or to skin multinucleate voluntary movement striated

aponeneurosis

attaches muscle to skin

origin

attachment of a muscle that remains relatively fixed during muscular contraction - immovable pr less movable bone

Insertion

attachment to movable bone

Name the specific spinal nerve and corresponding plexus that matches the description. Motor to deltoid muscle to abduct the upper arm

axillary nerve in brachial plexus

List the five major nerves that arise from the brachial plexus.

axillary, musculocutaneous, median, ulnar, radial

A graded potential is converted to an action potential at the _______ of the neuron.

axon hillock

Dorsal rami innervate the ________________ muscles and skin of the ________________.All ventral rami except ___________________ form plexuses. Instead of forming plexuses, these rami form the _____________________________________ nerves between the ribs.Which areas are supplied by these nerves?

back, back, anterolateral thorax, intercostal, •Intercostal muscles between ribs •Muscle and skin of anterolateral thorax •Abdominal wall

1. Why do you have to exercise vigorously for 30 minutes before you start burning fat?

bc it is used as a last resort as fuel to be broken down

functions of troponin

binds to actin, binds to tropomyosin / helps position tropomyosin on actin, binds calcium ions

functions of troppmyosin

blocks myosin binding sites on actin

Name the nerve plexus that matches the description: Five major nerves arise from this plexus and supply the arm

brachial plexus

Name the nerve plexus that matches the description: Sensory from skin of neck, back of head, and shoulders

brachial plexus

Name the nerve plexus that matches the description: Damage to this plexus can cause sensory loss, weakness, paralysis, and movement difficulties in the arm and hand

brachial plexus

Name the nerve plexus that matches the description: Innervates the upper limb (arm)

brachial plexus

Name the nerve plexus that matches the description: Most complex plexus

brachial plexus

Define tract

bundles of neuron processes/axon in CNS

Define nerve

bundles of neuron processes/axon in PNS

what cause the striations in skeletal muscle fibers when viewed under the microscope

caused by the repeating series of light and darknbamds in a myofibril

1. Alcohol consumption can impair your _____________________ resulting in poor judgment. It can impair your _________________________ resulting in loss of balance, proprioception deficits, and difficulty walking.

cerebellar function, cerebellum

Sensory and motor fibers entering and leaving the cerebral cortex are contralateral, but fibers entering and leaving the cerebellum are __________________________.

cerebral

The basal nuclei interact with the _________________________________ to influence muscle movements.Name two "movement" disorders that are associated with these two areas.

cerebral cortex Huntington's disease, Parkinson's disease

Name the nerve plexus that matches the description: Motor to muscles of the anterior neck

cervical plexus

Define nucleus

clusters of neuron cell bodies in CNS

Define ganglion

clusters of neuron cell bodies outside the CNS in the PNS

Name the specific spinal nerve and corresponding plexus that matches the description. Sensory and motor to anterior/lateral lower leg and dorsal foot (dorsiflexes foot, extends toes)

common/peroneal sciatic nerve in sarcal plexus

structure of thin actin filaments

composed of two strands of actin protein subunits twisted into a helix and contain sites for myosin head attachment during contraction. Looks like a twisted double strand of pearls

1. Describe the structure of the thin actin filaments.

composed of two strands of actin protein subunits twisted into a helix that contain sites for myosin head attachment during contraction

The RMP is generated because there are differences in the _____ of ions in the intracellular and extracellular fluids, and there are differences in the _____ of the plasma membrane to these ions.

composition, permeability

skeletal muscle tone

constant slightly contracted state of all muscles functions: keeps muscles trim healthy and ready to respond to stimulation, help stabilize joints, and helps maintain posture

The largest tract that allows the right and left cerebral hemispheres to communicate is the ___________________________________.

corpus callosum

what is the process by which direct phosphorylation of ADP by CP happens

creatine kinase transfers P from creatine phosphate to ADP to yield creatine & ATP

a high energy molecule stored in muscle and used to regenerate ATP

creatine phosphate (CP)

Sarcoplasm

cytoplasm of a muscle cell

How do muscle contractions help maintain body temperature?

dangerous heat levels are prevented by radiation of heat from the skin and sweating

what causes Parkinson's disease?

decreased dopamine production by substantia nigra

Most general sensory receptors are modified _______ endings of sensory neurons. Based on structure, these are called _______ receptors.

dendritic , sensory

What would happen if a surgeon accidentally cut both phrenic nerves?

diaphragm is paralyzed -> respiratory arrest

what are the 3 ways ATP is generated in muscle fibers

direct phosphorylation of ADP by CP anaerobic glycolysis aerobic / cellular respiration

The neurotransmitter that is deficient in Parkinson's disease and increased in schizophrenia is _______

dopamine

1. Cell bodies of sensory neurons are located in _____ roots. Cell bodies of motor neurons are located in the ______ roots.

dorsal, ventral

1. Each spinal nerve connects to the spinal cord by a ____________ root and ____________ root. Each root forms from _______________ that are attached to the spinal cord.

dorsal, ventral, rootlets

1. Describe the relationship of a nerve axon and a muscle fiber at the neuromuscular junction.

each axon branches into axon terminal that end in neuromuscular junction at a single muscle fiber

The least common type of functional synapse is the ______ synapse. The most common type of functional synapse is the ______ synapse.

electrical , chemical

"Natural opiates" that inhibit the transmission of pain signals to the brain make up the neurotransmitter category called ______. Which specific neurotransmitter increases during labor contractions?

endorphins, Enkephalin

Which glial cell helps produce and circulate cerebrospinal fluid?

ependymal

Describe Ependymal cells, including structure and function

epithelial cells that have many cilia. Functions include lining internal cavities of the brain and spinal cord, help produce cerebrospinal fluid, and cilia help circulate the CSF

characteristics of muscle tissue

excitability, contractility, extensibility, elasticity

Characteristics of epithelial tissue -

exhibit apical-basal polarity, Apical surfaces may be smooth and have microvilli or cilia, Basal surface lies on the basal lamina, Bound together by specialized contacts, Attached to a basement membrane, Supported by connective tissue, Avascular but innervated, & High rate of regeneration by cell division

A sensory homunculus demonstrates that the most sensitive body regions with the greatest number of receptors are the _____________, ____________, and ___________________.

face, lips, fingertips

A motor homunculus of the primary motor cortex illustrates that the most precise motor control is in the __________________, __________________, and __________________.

face, tongue, hands

The largest nerve of the lumbar plexus is the ________________ nerve.

femoral

Name the specific spinal nerve and corresponding plexus that matches the description. Motor to anterior thigh muscles (quadriceps etc) to extend the knee and flex the hip

femoral nerve in lumbar plexus

a muscle cell is also called a muscle _____

fiber

Describe Satellite cells, including structure and function

flattened cells that surround neuron cell bodies in ganglia

functions of myosin heads

form cross-bridges between thick myosin and thin actin filaments during contraction binding sites for thin actin filaments binding sites for ATP contain ATPase enzymes that split ATP for energy

Charateristics of smooth muscle

found in hollow organs uninucleate involuntary movement nonstriated

muscles contract with varying force and for different periods of time in response to stimulus varying ____ & _____

frequencies, intensifies

Increasing the strength of a stimulus does not increase the strength of an action potential but, instead increases the ______ of action potentials produced so that the stimulus (such as pain) is perceived to be more intense.In other words, a stronger stimulus does not generate a taller or bigger action potential. Instead, it generates more action potentials.

frequency

List the five lobes of the cerebrum. What are the basic functions of each lobe?

frontal - voluntary motor functions concentration planning verbal communication decision-making making and personality parietal - General sensory functions such as touch textures and shapes temporal - hearing and smelling (interpretation and storage) occipital - processes incoming visual information and stores visual memories insula (island) - memory and interpretation of taste

1. Damage to the primary visual cortex results in __________________________.If the visual association area is damaged, the person can see, but he cannot ___________.

functional blindness, comprehend

1. Approximately 20% of cells in the nervous system are neurons. The other 80% are ____ cells that support, protect, and nourish neurons.

glial

Name the specific spinal nerve and corresponding plexus that matches the description. Can be injured by poorly administered injection in buttock muscles

gluteal nerves in sacral plexus

Membrane potentials can be either localized short-distance signals called ___ potentials or long-distance signals called ____ potentials.

graded, action

Glycosome

granules of stored glycogen

1. Most limbic system output relays through the ____________________________.

hypothalamus

All neurons in the cerebral cortex are ____________________________.

interneurons

Proteins in the plasma membrane act as channels for the movement of ______.

ions

Describe Oligodendrocytes, including structure and function

large cells with bulbous body and sender processes and wrap around CNS neuron axons. Functions to produce myelin sheath in CNS which protects, insulates, and speeds up nerve conduction

Which axons will conduct action potentials more quickly? Larger diameter axons or smaller diameter axons Unmyelinated axons or myelinated axons

larger diameter axons, myelinated axons

phases of muscle twitch on a myogram

latent - muscle tension no shortening contraction - muscle shortens and tension increases relaxation- calcium is pumped back, myosin detaches, tension declines, and muscle lengthens

1. The "emotional brain" is the ____________________ system. Where is this "functional" brain system located? List some components of this system.

limbic a. Encircle the corpus callosum and thalamus b. Cingulate gyrus, Hippocampus and parahippocampal gyrus, amygdala, olfactory bulbs and tracts

Name the nerve plexus that matches the description: Femoral nerve arises from this plexus

lumbar plexus

Name the nerve plexus that matches the description: Motor to the anterior/medial thigh muscles and abdominal wall muscles

lumbar plexus

All encapsulated nerve endings are _______. List and define five types of encapsulated nerve endings.

mechanoreceptors a. Meissner's (tactile) corpuscles - discriminative & light touch, Pacinian (lamellar) corpuscles - deep pressure (first applied) & vibration (on/off), Ruffini endings - deep continuous pressure, Muscle spindles - muscle stretch, Golgi tendon organs - stretch in tendons, Joint kinesthetic receptors - stretch in articular/joint capsules (joint position/motion)

Name the specific spinal nerve and corresponding plexus that matches the description. Compressed in carpal tunnel syndrome

medial nerve in brachial plexus

Name the specific spinal nerve and corresponding plexus that matches the description. Injury causes difficulty with pincer grasp (gripping between thumb and index finger)

median nerve in brachial plexus

Name the specific spinal nerve and corresponding plexus that matches the description. Motor to muscles that pronate forearm, flex wrist/fingers, and oppose thumb

median nerve in brachial plexus

Most CNS tumors form from ___ or __ _. WHY?

meninges, glial cells They are in supporting tissues that can undergo mitosis

Which glial cell would be found in abundance on a histology slide of infected brain tissue?

microglia

Describe Astrocytes , including structure and function

most abundant glial cell, many cell processes. Functions include forming blood-brain barrier, structural framework, aids in development of neurons and synapses in fetal brain, divide and occupy empty spaces left by dead

The most abundant structural neuron type in the human body is the _____ neuron. 99% of neurons in the body are this type and function as _____.

multipolar, interneurons

All motor neurons are ____ neurons. Interneurons are ____ neurons.

multipolar, multipolar

Which cell types have excitable membranes and are able to send action potentials?

muscle cells

which happens more quickly- muscle contraction or relaxation

muscle contraction

eccentric contraction

muscle lengthens example: calf muscle as you walk up a steep hill

isotonic contraction

muscle shortens because muscle tension exceeds load which produces a movement example: walking, lifting a book, swinging a tennis racket

1. Why must ATP be regenerated quickly?

muscles store only enough ATP for 4-6 seconds worth of activity

The medulla oblongata contains nuclei of cranial nerves _____, _____, _____, and ______.What might be some symptoms related to damage of these nuclei?

nerves vestibulocochlear (8), glossopharyngeal (9), vagus (10) and hypoglossal (12).

structure and function of the sarcoplasmic reticulum

network of smooth endoplasmic reticulum surrounding each myofibril stores and releases calcium to initiate muscle contraction

1. Describe the structure and functional role of the sarcoplasmic reticulum.

networks of smooth endoplasmic reticulum stores calcium and releases calcium to initiate muscle contraction

1. A nerve cell is called a _____________________________. It is made of three basic parts: the _____________________ or _____________ that contains the DNA and organelles, ________________ that receive signals, and an ________________ that transmits signals.

neuron,cell body, soma,

When an action potential arrives at the axon terminal, synaptic vesicles release a ______ by _____. This substance diffuses across the ______ cleft and binds to receptors on the ______ membrane, causing a response in the receiving membrane.

neurotransmitter, synaptic vesicles, synaptic, postsynaptic neuron

What is an indirect-acting transmitter?

neurotransmitters that binds to a G protein-linked receptor and acts through an intracellular second messenger that cause slow, complex, long-lasting responses

1. Is all of the energy released during muscle contraction converted to useful work?

no

1. Does increasing the stimulus intensity or strength beyond the maximal stimulus produce a stronger contraction? Explain.

no all the muscle motor units are recruited

isometric contraction

no shortening; muscle tension increases but does not exceed load example: trying to lift a car, pushing on a wall, maintaining upright position , holding a heavy object

The neurotransmitters released by the sympathetic division of the autonomic nervous system are _____ and ________.

norepinephrine, epinephrine

Name the specific spinal nerve and corresponding plexus that matches the description. Sensory and motor to medial thigh (adducts thigh)

obturator nerve in lumbar plexus

Name the specific spinal nerve and corresponding plexus that matches the description. Sensory from skin of anterior thigh and medial leg from knee to foot

obturator nerve in lumbar plexus

The primary visual cortex and the visual association area are located in the _____________ lobe. The primary visual cortex receives visual information from the ___________________ retina. The visual association area uses past visual experiences to interpret visual information and recognize and appreciate objects seen.

occipital, contralateral

The cell bodies of which two cranial nerves are located in special sense organs?

olfactory and optic

There are 12 pairs of cranial nerves. Which ones are purely sensory? Which ones are motor? Which ones are both sensory and motor?

olfactory and optic

Myelin sheaths in the central nervous system are produced by neuroglial cells called _____

oligodendrocytes

load

opposing force exerted on a muscle by the weight of the object to be removed

Damage to the primary motor cortex (such as may happen with a stroke) paralyzes muscles on the __________________ side of the body, but only __________________ control is lost because muscles can still contract reflexively.

opposite, voluntary

Merocrine gland -

package products into vesicles and secrete by exocytosis

1. Severe injury to the reticular activating system results in _____________

permanent unconsciousness (coma).

Name the specific spinal nerve and corresponding plexus that matches the description. Irritation of this nerve causes hiccups

phrenic nerve in the cervical plexus

An important part of the epithalamus is the ________________ gland. What is its function?

pineal a. Secretes melatonin which helps regulating

The hypothalamus connects to the _________ _________ by a stalk called the infundibulum.

pituitary gland

Sarcolemma

plasma membrane of a muscle cell

Neurons, like all cells, have a resting membrane potential which is due to a difference in charge across the membrane. The outside of the membrane is more ______ compared to the inside of the membrane which is more ______. The RMP of neurons is approximately ___ mV on the inside of the plasma membrane. The ability of neurons to rapidly change their RMP in response to a stimulus allows neurons to conduct electrical nerve impulses known as _____.

positively, negatively, -70, action potential

The primary somatosensory cortex is contained in the ____________________ gyrus of the __________________ lobe. It receives sensory information from general somatic receptors in the ___________ and from proprioceptors in ___________________________________. Each hemisphere receives sensory input from the ___________________ side of the body.

postcentral, parietal, skin, skeletal muscles, joints, tendons, left

The primary motor (somatic) motor cortex is located in the ______________________ gyrus of the ________________ lobe. ________________________ neuron cells with long axons project to the contralateral side of the spinal cord, forming motor tracts called pyramidal or _____________________ tracts. These neurons control ________________ movement of _________________ muscles on the opposite side of the body.

precentral, frontal, large, corticospinal, voluntary, skeletal

The anterior association cortex or ______________ cortex is located in the _________ lobe. Its abilities develop slowly and depend on feedback from our ______________ environment.List some abilities that the AAC is involved with.

prefrontal, frontal, social a. Intellect, cognition (complex learning abilities), recall, personality, judgment, reasoning, persistence, planning, initiative, abstract ideas, decision making, conscience

Just anterior to the precentral gyrus in the frontal lobe is the ___________________ cortex. It helps plan or coordinate motor movements by sending impulses to the _______________ ________________ cortex and to the _____________ ______________. It choreographs basic movements into more complex or skilled motor activities. Name one example of a complex task that this area helps control.

premotor, primary motor, spinal cord a. Playing musical instrument, typing

A nerve axon may also be called a nerve ____________________.

process

what are the most important functions of muscle

produce movement of Bones facial muscles and fluids maintain posture and body position stabilize joints generate heat

Receptors that monitor muscle position and movement are called _____. Information about the length of muscles is relayed to the nervous system by receptors called __________. Information about the amount of tension in a muscle is relayed to the nervous system by receptors called ________.

proprioceptors, muscle spindles, Golgi tendon organs

Functions of epithelial tissue -

protection, absorption, filtration, excretion, secretion, and reception of sensory signals

Name the specific spinal nerve and corresponding plexus that matches the description. Injury results in inability to extend the wrist (wrist drop)

radial nerve in brachial plexus

Name the specific spinal nerve and corresponding plexus that matches the description. Motor to muscles that supinate forearm, extend elbow/wrist/fingers

radial nerve in brachial plexus

Myasthenia gravis is an autoimmune disease that causes muscle weakness and paralysis by destroying ______ for acetylcholine.

recetors

Myoglobin

red pigment that stores oxygen

1. The main sensory component of the reticular formation is the __________ system. What is its function?

reticular activating a. Keeps cerebral cortex conscious, alert, and excitable

Name the nerve plexus that matches the description: A nerve of this plexus controls urination, defecation, and erection

sacral plexus

Name the nerve plexus that matches the description: Innervates buttock, posterior thigh, lower limb, pelvic structures, and perineum

sacral plexus

the functional unit or the smallest contractile unit of skeletal muscle is a ______

sacromeres

Which glial cell would be found surrounding cell bodies of neurons in a dorsal root ganglion?

satellite cells

Name the specific spinal nerve and corresponding plexus that matches the description. Lies under the gluteus maximus muscle

sciatic nerve in sarcal plexus

Name the specific spinal nerve and corresponding plexus that matches the description. Innervates entire lower limb (except anteriomedial thigh)

sciatic nerve in the sacral plexus

Name the specific spinal nerve and corresponding plexus that matches the description. Longest and thickest nerve of the body

sciatic nerve in the sacral plexus

A specific autoimmune disease attacks oligodendrocytes and myelin sheaths and causes myelin degeneration in the CNS. The areas of demyelination are replaced by scar tissue or ______. The disease is called __________.

sclerosis, multiple sclerosis

All bipolar neurons are _____ neurons.

sensory

1. Dorsal roots of the spinal cord contain __________________________ fibers/axons whose cell bodies are located in the ________________________________. Ventral roots of the spinal cord contain __________________________ fibers/axons whose cell bodies are located in the _______________________________ of the spinal cord.

sensory, dorsal root gangliia, motor, ventral horn

1. The peripheral nervous system is divided into the ______ division that carries information to the CNS and the ______________________ division that carries information away from the CNS.

sensory, motor

The two types of neurons in the peripheral nervous system are ____ neurons that respond to a stimulus and send information about this stimulus to the CNS and ____ neurons that transmit information from the CNS to muscles and glands.

sensory, motor

When testing stretch reflexes, a positive result indicates that the _____ and _____ connections between the muscle and the spinal cord are intact.

sensory, motor

Two neurotransmitters involved in sleep/wakefulness and appetite are ______ and _______

serotonin, histamine

cocentric contraction

shortening of muscle example: picking up a book, kicking a ball

Describe Microglial, including structure and function

small oval cells with long thorny processes. Functions include transform into phagocytic macrophages and migrate toward injured/dead/endangered neurons

The motor division of the peripheral nervous system is divided into the _________________ division that controls _________________ muscle and the ____________________ division that controls _______________ muscle, _______________ muscle, and ______________.

somatic nervous system, skeletal, autonomic nervous system, cardiac, smooth, glands

The ____________________ ____________________ cortex receives information from the primary somatosensory cortex and integrates that information to produce an understanding of an object being felt (size, shape, texture, parts) and to recognize that object without even seeing it.

somatosensory association

Some receptors do not adapt, but instead respond continuously to _______ at a constant rate. They do not adapt because they need to be responsive for stimuli. Give three examples of receptors that do not adapt.

stimuli a. Equilibrium receptors of inner ear, nociceptors, proprioceptors

Energy sources during exercise

surge of power - direct phosphorylation longer bursts of energy- anaerobic glycolysis prolonged activity that requires endurance - aerobic respiration

The autonomic division is further divided into the ______________________ division that is responsible for the ________________ or ________________ response in times of stress and the ___________________________________ division that maintains automatic internal body functions during rest.

sympathetic, fight, flight, parasympathetic

The area between a neuron and its target cell (muscle, gland, or another neuron) is known as a _____

synapse

Simple general sensory receptors detect the two T's and two P's. They detect sensations related to ______, _______, ________, and ______ .Structurally, they are classified as unencapsulated (free) nerve endings________________ or _______________.

tactile sensation, temp monitoring, pain sensation, proprioception, unencapsulated (free) nerve endings, encapsulated nerve endings

The olfactory cortex in located in the medial aspect of the _______________________ lobe.

temporal

The primary auditory cortex and the auditory association area are located in the _________________ lobe. They work together to allow us to hear and interpret sound and to store memories of sounds.

temporal

what is the difference between a tendon and a ligament

tendon: connects muscle to bone ligament: connects bone to bone

The ______________ is called the "gateway to the cerebral cortex."Why is this part of the brain called this?

thalamus Relay station for info coming into cerebral cortex

excessive post-exercise oxygen consumption & functions

the amount of oxygen that must be inhaled following exercise to restore pre-exercise conditions functions: Refreshes oxygen reserves, glycogen stores, and ATP and CP reserves. Converts lactic acid to pyruvic acid, glucose, or glycogen (in the liver > gluconeogenesis)

muscle tension

the force exerted by a contracting muscle on an object

1. Describe how an action potential is generated.

the local depolarization find acetylcholine to open chemically gated ion channels. sodium and feast in and potassium is diffused out and this produces a local change in membrane potential. the generation and propagation of an action potential across the sarcolenma. repolarization restores the sarcolemma to its original membrane potential which means potassium goes out so the cell can return to a negative charge

threshold

the minimum voltage needed to generate an action potential in a muscle fiber and produce a single contraction (twitch)

describe the divisions of the nervous system. Which division conducts impulses to skeletal muscles?

the nervous system is consisted of the cqentral nervous system which is the brain and spinal cord the peripheral nervous system are the neurons outside the CNS. the somatic nervous system conducts impulses to skeletal muscles

muscle fatigue & causes

the physiological inability of a muscle to contract caused ionic balances mainly potassium and sometimes prolong exercises * lack of ATP not a cause

muscle twitch

the response of a muscle (motor unit) to a single brief threshold stimulus

Peripheral nervous system axons may regenerate after injury, but central nervous system neurons do not regenerate after injury. Why don't CNS neurons regenerate?

they cannot undergo mitosis

1. If the spinal cord is cut or transected at any level, there will be total loss of ______________ and _________________ functions below the level of the cut.If the spinal cord is cut in the cervical region, all four limbs are paralyzed. This is called _________________________.If the spinal cord is cut between T1 and L1, both lower limbs will be paralyzed. This is called _________________________.

thigh, leg

An action potential cannot be produced in a neuron unless a stimulus is strong enough to cause the neuron to reach _____

threshold

Name the specific spinal nerve and corresponding plexus that matches the description. Sensory and motor to posterior leg and plantar foot (extends thigh, flexes knee/toes, plantar flexes foot)

tibial nerve in scaitic nerve

Name the specific spinal nerve and corresponding plexus that matches the description. Sensory from skin of the pinky finger

ulnar nerve in brachial plexus

Name the specific spinal nerve and corresponding plexus that matches the description. Causes "funny bone" tingling when you hit your elbow

ulnar nerve in the brachial plexus

Most sensory neurons are ___ neurons whose cell bodies are located in _____

unipolar, ganglia of PNS

graded muscle responses

variations in the degree of muscle contraction based on demands placed on muscles and needed for control of skeletal movement *responses are graded by changing the frequency or strength of the stimulus

Hollow cavities or chambers in the brain that are continuous with the spinal cord are called _______. The cells that line these cavities are called _______cells.

ventricles, ependymal

Complex sense organs that contain nervous sensory cells and other types of cells are associated with the special senses of ____, ____, _____, _____, and ____ . These complex sense organs are located in the____, _____, ____, and _____.

vision, hearing, equilibrium, smell, taste, eyes, ears, nose, mouth.

Degeneration of the distal end of a severed axon is called _____ degeneration.

wallerian

characteristics of cardiac muscle

walls of heart uninucleate involuntary movement striated

Describe Schwann cells, including structure and function

wrap around PNS axons and from myelin sheaths