Exam 3 terms Flashcards

1
Q

myology

A

the study of muscles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

striations

A

Cross-banded appearance of muscle tissue under the microscope, indicating the presence of sarcomeres.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Fascicle

A

a bundle of myofibers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

sarcolemma

A

plasma membrane of a muscle cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

sarcoplasm

A

cytoplasm of muscle cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

sarcoplasmic reticulum (SR)

A

smooth endoplasmic reticulum (ER)of muscle cells. SR is well-developed in skeletal muscle myofibers and is wrapped in a highly organized pattern around myofibrils

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

terminal cisternae

A

Repeated expanded sections of the SR that lie adjacent to T-tubules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

transverse tubules (T-tubules)

A

are narrow membranous tunnels formed from and continuouswith the sarcolemma. Functionis to transmit action potentialsfrom surface to interior of myofibers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

triad

A

one T-tubule + two adjacent terminal cisterns of SR

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

myofibril

A

Myofibrils are elongated strands of protein complexes found inside myofibers.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

sarcomere

A

Myofibrils are organized into longitudinally repeated subunits called “sarcomeres”, which are composed of alternating light and dark zones.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

I-Band

A

Light zonesare called I-Bands containing only thin myofilaments (one of the components of a sarcomere).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

A-Band

A

Dark zonesare called A-Bandscontainingthick myofilaments and overlapping thin myofilaments (one of the components of a sarcomere)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Z-Disk

A

a dense line composed of -actinin that attaches the thin myofilaments of adjacent sarcomeres.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

titin

A

performs two functionsin sarcomeres: 1)It helps hold the thick filaments in proper alignment, and 2)its elasticity helps return a stretched sarcomere to its original resting length.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

H-Zone

A

area within the A-band where only thick filaments exist

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Bare zone

A

middle portion of H-zone lacking myosin heads

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

M-line

A

a dark line in the middle of the bare zone that contains proteins that are critical for organization and alignment of the thick filaments

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

thick myofilaments

A

contain myosin and titin; consist of approximately 2500 myosin moleculeswith their tails wound together and myosin heads projecting outward toward surrounding thin filaments.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

thin myofilaments

A

are made of proteins: Nebulin, F-Actin, Tropomyosin, & Troponin.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

nebulin

A

a structural protein that lies alongside thin filaments and attaches the thin myofilamentsto the Z-disks.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

F-Actin (filamentous actin)

A

is a filamentous polymer consisting of G-actin (globular actin) subunits arranged in twoF-actin strands that twist together to form a helix.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

G-Actin

A

The “pearl” on the thin filament; each on contains a myosin binding site.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Tropomyosin

A

filamentous protein that lies in the groove between the F-actin strands. Each tropomyosin molecule spans seven G-actin subunits.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

Troponin

A

a Ca2+-binding protein that binds at regular intervals along tropomyosin molecules

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

Neuromuscular junction (NMJ)

A

is the synapse where the nervous system communicates with skeletal muscles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

synaptic cleft

A

Space between the end of the synaptic bulb and the sarcolemma of the myofiber. 20 to 30 nm (10-9meters)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

motor endplate

A

A specialized region of the sarcolemma of the myofiber where the synaptic bulb of the alpha-motor neuron sits. This region of the sarcolemma is made up of a series of membrane folds containing a high density of nicotinic cholinergic receptors.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

nicotinic receptor

A

Nicotinic receptorson the myofibers are ligand-gated Na+,K+channels that open when ACh binds to them, allowing Na+to flow into the myofiber and K+to flow out.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Dihydropyridine (DHP) receptor

A

In the triads, the T-tubules contain voltage-sensing dihydropyridine (DHP) receptors that are mechanically linked to Ca+2-release channels called ryanodine receptors (RyR) in the adjacent sarcoplasmic reticulum (SR).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
31
Q

Ryanodine receptor (RyR)

A

In the triads, the T-tubules contain voltage-sensing dihydropyridine (DHP) receptorsthat are mechanically linked to Ca+2-release channels calledryanodine receptors(RyR)in the adjacent sarcoplasmic reticulum (SR).

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
32
Q

Acetylcholinesterase

A

an enzyme found in synaptic cleft, rapidly degrades ACh

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
33
Q

Motor unit

A

consists of an -motor neuron and all of the myofibers (muscle cells) that it stimulates.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
34
Q

Twitch contraction

A

A brief response of a single motor unit. A twitch contraction is the muscle movement generated in response to a single AP moving down an -motor neuron and stimulating its myofibers.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
35
Q

myoglobin

A

is an O2-storage protein found in muscle cells. This protein contains an iron-containing heme group which gives slow-twitch muscle its red appearance.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
36
Q

slow-twitch muscle fibers

A

Red muscle; have slow contraction and relaxation but are very resistant to fatigue and small diameter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
37
Q

fast twitch/glycolytic fibers

A

White muscle; have a fast contraction and relaxation time but fatigue quickly and large diameter.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
38
Q

fast twitch/oxidative fibers

A

Pink muscle; have fast contraction and relaxation with intermediate fatigue level and diameter.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
39
Q

summation

A

is the process of adding together individualtwitch contractions to increase the overall strengthof muscle contraction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
40
Q

Multiple motor unit summation (recruitment)

A

occurs when multiple
motor units are stimulated to contract simultaneously in a muscle, thus increasing the overall strength of a muscle contraction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
41
Q

Wave (frequency) summation

A

frequency of an individual motor unit is increased so that the overall tension is greater

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
42
Q

tetany or tetanus

A

“steady state of muscle contraction” wave summation results in sustained contraction

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
43
Q

tetanus “lock jaw”

A

is pathological condition caused by Clostridium

tetani toxin.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
44
Q

motor nucleus

A

A given skeletal muscle is served by a group of motor neurons, whose cell bodies are grouped together in the spinal
cord (or brainstem) to form a motor nucleus. Found in the ventral horn of gray matter.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
45
Q

Fatigue

A

Decrease in work capacity of a muscle caused by work itself.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
46
Q

Rigor

A

is extreme fatigue that occurs when ATP is completely depleted in
a myofiber.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
47
Q

rigor mortis

A

Rigor mortis is the stiffening of a dead body that occurs a few hours after death of an animal. Body becomes stiff because ATP is not being produced by cells and Ca+2 leaks from SR

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
48
Q

phasic smooth muscles

A

undergo periodic cycles of contraction and relaxation. So, the major function of phasic smooth muscle is to develop
force, shorten, and then relax similar to skeletal muscles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
49
Q

tonic smooth muscles

A
contract continuously (tonically) to maintain an organ’s dimensions against an imposed load or to keep a sphincter
closed.
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
50
Q

dense bodies

A

Actin myofilaments are attached to dense bodies, which serve a function
similar to Z-disks in skeletal muscles.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
51
Q

attachment plaques or membrane-dense areas

A

are dense bodies associated with inner surface of membranes of smooth muscle cells.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
52
Q

multi-unit smooth muscle

A

cells are NOT electrically connected by gap junctions. Each smooth muscle cell is individually stimulated at neuroeffector junctions by ANS motor neurons. (iris & ciliary body)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
53
Q

contact junctions

A

allow rapid and precise nervous system control of these smooth muscles. found in multi unit smooth muscle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
54
Q

single unit (unitary) smooth muscle

A

“Visceral type”- Found in walls of viscera (internal organs). 99% of all smooth muscle is this type.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
55
Q

diffuse junctions

A

(80 to 120 nm synaptic cleft). Diffuse junctions are slow to activate. found in unitary smooth muscles

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
56
Q

calmodulin

A

a Ca2+ binding protein similar to troponin

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
57
Q

myosin light chain kinase (MLCK)

A

Ca2+ calmodulin complex binds to and activates this that phosphorylates the myosin light chain called the regulatory chain, which is found associated with the myosin head.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
58
Q

macronutrient (fuel)

A

An organic compound (lipids, carbohydrates, and proteins) that can be broken down (degraded or catabolized) in the body to produce usable energy (e.g. ATP)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
59
Q

metabolism

A

the sum of all physical and chemical changes that take place within an organism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
60
Q

anabolism

A

(Biosynthesis) -all processes in which simpler substances are assembledinto more complex substances,usually requiring energy input

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
61
Q

catabolism

A

(Degradation) -all processes in which complex substances are broken down into simpler substances, usually with the concomitant release of energy

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
62
Q

Adenosine triphosphate (ATP)

A

ATP is “energy currency” ATP + H2O ADP + Pi+ ENERGY for work

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
63
Q

ingestion

A

is to take into the body through the mouth.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
64
Q

digestion

A

Breakdown of food into smaller physical and chemical units that can be eventually be absorbed from the lumen of the GI tract into bloodstream.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
65
Q

mechanical digestion

A

Breakdown of food based on movements ofthe GI tract

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
66
Q

chemical digestion

A

Breakdown of food based on enzyme-catalyzed hydrolysis reactions occurring in lumen of GI tract.

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
67
Q

absorption

A

Passage of digested components of food from lumen of GI tract into the blood (or lymph)for distribution to all the cells of the body.

68
Q

defecation

A

The elimination of indigestiblesubstances from the GI tract as feces

69
Q

mastication

A

is the process of chewing

70
Q

bolus

A

is a soft, flexible food mass that can be easily swallowed

71
Q

salivary amylase (ptyalin)

A

begins breakdown of starches into maltose and dextrins; (limited in horses, and absent in ruminants and carnivores)

72
Q

deglutition

A

“swallowing” is the process that movesthebolus of food from the mouth to the stomach

73
Q

chyme

A

thin liquid layer formed by mixing the bolus with gastric juice.

74
Q

peptic (chief or zymogenic) cells

A

secretes pepsinogen

75
Q

zymogen

A

a pre-enzyme

76
Q

pepsinogen

A

is a zymogen (an inactive precursor) of pepsin

77
Q

pepsin

A

is a protease, which is an enzyme that digests proteins. Pepsin requires an acidic pH to catalyze the digestion of proteins

78
Q

parietal (oxyntic) cells

A

secrete HCl & intrinsic factor

79
Q

intrinsic factor

A

essential for Vitamin B12absorption

80
Q

gastrin

A

a hormone secreted by G-cells Gastrin stimulates increased gastric motility and the secretion of gastric juice rich in HC

81
Q

segmentation

A

is a process involving the alternating contraction and relaxation within a single segment of the GI tract. (for mixing)

82
Q

acinar cells

A

constitute 99% of pancreatic cells and the exocrine portion of the pancreas. Acinar cells produce the secretions that form pancreatic juice.

83
Q

sphincter of Oddi

A

is a valve around the hepatopancreatic ampulla that controls the flow of pancreatic juice and bile into the duodenum

84
Q

Enterokinase (enteropeptidase)

A

enzyme produced by the duodenal mucosa. converts trypsinogen to trypsin

85
Q

pancreatic amylase

A

hydrolyzes starches into maltose, maltotriose, and dextrins

86
Q

pancreatic lipase

A

is the principal triglyceride-digesting enzyme in an animal; Triglyceride →2 fatty acids+ monoglyceride

87
Q

ribonuclease (RNase)

A

hydrolyzes RNA

88
Q

deoxyribonuclease (DNase)

A

hydrolyzes DNA

89
Q

secretin

A

Stimulates sodium bicarbonate secretion by acinar cells.

90
Q

cholecystokinin (CCK)

A

stimulates secretion of pancreatic juices, also stimulates opening of sphincter of Oddi.

91
Q

intestinal brush border enzymes

A

are enzymes produced by the absorptive SI epithelial cells and associated with the microvilli (brush border)of these cells.

92
Q

endopeptidase

A

enzymes that hydrolyze internal peptide bonds within proteins thus breaking proteins into smaller peptides

93
Q

exopeptidase

A

enzymes that hydrolyze the peptide bonds that attachthe C-or N-terminal amino acids to a proteinor peptide thus releasing individual amino acids

94
Q

trypsin

A

Pancreatic endopeptidase that hydrolyzes proteins into peptides.

95
Q

chymotrypsin

A

Pancreatic endopeptidase that hydrolyzes proteins into peptides.

96
Q

carboxypeptidase

A

Pancreatic exopeptidase that hydrolyzes peptide bond that attaches the carboxyl-terminal amino acid to the peptide

97
Q

aminopeptidase

A

exopeptidase that hydrolyzes peptide bonds that attach amino-terminal amino acids to peptides

98
Q

dipeptidase

A

splits dipeptides into amino acids.

99
Q

Alpha-dextrinase

A

A brush border enzyme that clips of one glucose unit at a time from smaller fragments of starch and alpha-dextrins.

100
Q

maltase

A

A brush border enzyme that splits maltose and maltotriose into two or three molecules of glucose

101
Q

sucrase

A

A brush border enzyme that splits sucrose (common table sugar) into glucose and fructose

102
Q

lactase

A

A brush border enzyme that hydrolyzes lactose (milk sugar) into glucose and galactose

103
Q

micelle

A

a way to transport fats; soap bubbles are a form of micelles; After forming micelles with bile salts, long-chain fatty acids and monoglycerides are absorbed into intestinal epithelial cells by simple diffusion..

104
Q

chylomicrons

A

Once inside intestinal epithelial cells, fatty acids and monoglycerides are resynthesized into triglycerides. These triglycerides, along with cholesterol,are then incorporated into protein-coated spherical masses called chylomicrons.

105
Q

lipoprotein lipase

A

(an enzyme found on the endothelial cells lining these tissues) catalyzes breakdown of triglycerides into fatty acids (FA) and glycerol

106
Q

feces

A

consists of water, inorganic salts, sloughed-off epithelial cells, bacteria, products of bacterial decomposition, and undigested components of food

107
Q

Haustral churning

A

(haustrum = pouch of colon) involvesa haustrum relaxingand filling up until it becomes distended. Once it distends to a certain point, the walls contract and squeeze the contents into the next haustrum

108
Q

ruminants

A

are animals that regurgitate and remasticate their food.

109
Q

Rumination

A

Process of bringing food material from the forestomach back to mouth for further mastication

110
Q

Regurgitation

A

Bolusof foodis brought back to the mouth from the reticulum and rumen

111
Q

Remastication

A

Bolus (cud) is re-chewed 100 times or more.

112
Q

Reinsalivation

A

Saliva is added to regurgitated bolus.

113
Q

Redeglutition

A

Bolus is swallowed after remastication.

114
Q

Fermentation

A

The anaerobic breakdown of organic substances (primarily plants materials) in foods by bacteria and other microorganisms.

115
Q

Cellulose

A

Only digestible by microbes (estimated to represent more than 50% of all chemical energy in plants) hemicellulose, pectins, and fructosans.

116
Q

Volatile fatty acids (VFAs)

A

short chain fatty acids that are products of bacterial fermentation

117
Q

eructation

A

“belch without the noise”. During rumination, cattle produce 30-50 liters of gas per hour and sheep produce about 5 liters/hour. occurs once per minute

118
Q

Rumen(paunch)

A

Primary functions of the rumen are mixing, soaking, fermentation of ingested foods, and absorption of volatile fatty acids (VFA)

119
Q

Reticulum(honeycomb)

A

When feed, water,and saliva enter the reticulorumen through esophageal opening, heavy objects (grain, rocks, nails) fall into reticulum, while lighter material (grass, hay) enters the rumen

120
Q

hardware disease

A

Sharp objects like nails or wire that collect in the reticulum can cause this the can puncture the reticulum, diaphram, and pericardium of heart.

121
Q

omasum (Bookstomach, many plies)

A

Omasum is a site of: 1)continued fermentation, and 2)absorption of VFAsand bicarbonate before digesta enters abomasum.

122
Q

abomasum(true stomach)

A

Performs glandular stomach functions

123
Q

forestomach

A

Higher part of the GI tract; reticulum and rumen

124
Q

Intercalated discs

A

Area where each cardiac muscle cell physically contacts neighboring muscle cells; contain gap junctions and desmosomes

125
Q

autorhythmic cells

A

The heart’s AP conduction system consists of weakly contractile cardiac muscle that are specialized for generation and distribution of AP throughout the myocardium.

126
Q

slow response APs

A

used in autorhythmic(pacemaker) cells of the sinoatrial (SA) node, internodal pathway, atrioventricular (AV) node, bundle of His, and bundle branches

127
Q

fast response APs

A

are used in the normal contractile cardiac muscle cellsand Purkinje fibers of the heart

128
Q

Sinoatrial (SA) node

A

contains autorhythmic cells called pacemaker cells that spontaneously initiate slow response action potentials at a rate of ≈100 times/min does not require excitation by nervous system

129
Q

pacemaker cells

A

autorhythmic cells in SA node

130
Q

myogenic pacemaker

A

is made of muscles cells; creates slow response APs

131
Q

I_f-channels

A

Slow response APs are created in pacemaker cells by these “funny channels”. leak Na+ until Vm = (-50mv)

132
Q

T-type voltage-gated Ca2+ channels

A

(T stands for transient). Ca+2 will flow through these channels eventually bringing the cell to threshold(≈-40 mV).

133
Q

L-type voltage-gated Ca2+ channels

A

(Lstands for Long-lasting) when Vm reaches threshold open leading to the rapid depolarization of these cells as Ca+2 flows into the cells and depolarizes their membrane

134
Q

Systole

A

=contraction

135
Q

Diastole

A

=relaxation (dilate)

136
Q

internodal pathway

A

To excite ventricular muscle cells, AP from SA node travels through this

137
Q

Atrioventricular (AV) node

A

is the only electrical connection between atria and ventricles. also has pacemaker (depolarizes 40-60/min)

138
Q

Atriaventricular bundle (bundle of His)

A

From the AV node, slow response APs move here

139
Q

Bundle branches

A

Action potential spreads from AV bundle into the right and left bundle branches, which run through interventricular septum, to apex of the heart and up both sides of the heart

140
Q

Purkinje fibers

A

branch off of the bundle branches and conduct fast response AP (described below)into the contractile muscle cellsof the ventricular myocardium and papillary muscles

141
Q

Ca2+ induced Ca2+ release

A

Ca+2 flows into the cell from the ECF and stimulates opening of ryanodine receptor channels in the SR causing flow of Ca+2 out of the SR, creating Ca+2 sparks.

142
Q

electrocardiogram (ECG or EKG)

A

The EKG is a composite of action potentials produced by all the heart muscle fibers during each heartbeat

143
Q

P wave

A

= Atrial depolarization, which is spread of AP over atria

144
Q

QRS complex

A

=Ventricular depolarization, which is the spread of AP over the ventricles (Atrial repolarization is hidden within the large QRS complex. )

145
Q

T wave

A

=Ventricular repolarization,which occurs just before ventricles start to relax.

146
Q

hemodynamics

A

are the principles that describe the movement of blood in the circulatory system.

147
Q

resistance

A

primarily due to the friction between flowing blood and the walls of blood vessels (influenced by; Length of the tube (l), Viscosity of the fluid (n), & Radius of the tube (r)

148
Q

laminar flow

A

When blood flows in a long smooth vessel it streamlines into layers with the contents of each layer staying the same distance from the vessel wall.

149
Q

velocity of flow

A

is the distance that a fixed volume of blood travels in a given period of time (cm/sec or cm/min) v=Q/A

150
Q

mean arterial pressure

A

is blood pressurein thelarge arteries averaged over time

151
Q

diastolic blood pressure

A

When turbulence subsides (Korotkoff sounds no longer heard) ( when ventricles relax)

152
Q

systolic blood pressure

A

turbulent blood flow is heard when cuff pressure falls below the maximum

153
Q

Sphygmomanometer

A

Used to measure blood pressure

154
Q

Total peripheral resistance (TPR)

A

= Rarteries+ Rarterioles+ Rcapillaries+ Rvenules+ Rveins

155
Q

cardiac output (CO)

A

The amount of blood ejected by the left (or right) ventricle into the aorta (or pulmonary trunk) per minute.

156
Q

Stroke volume (SV)

A

(volume per beat) ×Heart Rate (HR; beats/min)

157
Q

heart rate (HR)

A

beats/min

158
Q

Frank-Starling law

A

The volume of blood ejected by the ventricle (SV) depends on the volume present in the ventricle at the end of ventricular diastole

159
Q

End diastolic volume (EDV)

A

Same as the Frank-Starling Law

160
Q

Preload

A

same as end diastolic volume and Frank-Starling law

161
Q

skeletal muscle pumping (milking)

A

Contraction of skeletal muscles pumps blood in the veins back to the heart. Valves in the veins keep the blood moving toward the heart.

162
Q

Respiratory pump

A

caused by movements of the diaphragm during breathing.

163
Q

Cardiovascular center (CVC)

A

ANS control of CO comes primarily from here (CVC) located in medulla oblongata (and pons) of the brainstem.

164
Q

Cardiac accelerator nerves

A

Sympathetic neurons extend from the CVC down the spinal cord and emerge out of sympathetic trunk ganglia) as the cardiac accelerator nerves that innervate the SA and AV nodes, and most portions of the ventricular myocardium

165
Q

baroreceptors

A

pressure receptors in the aorta and carotid arteries

166
Q

chemoreceptors

A

in the aorta and carotid arteries monitor chemical changes in blood (pH, CO2, O2) and under certain conditions can initiate neural reflex pathways that control HR