exam 4 Flashcards
(185 cards)
1
Q
what are the components of a circulatory system
A
fluid, pump, vessels
2
Q
what does fluid, pump, and vessels do in circulatory system
A
fluid- carries transported molecules and cells
pump- moves the fluids
vessels-carry fluid between pump and body tissues
3
Q
open circulatory systems have
A
hemolymph moves through vessels that open into extracellular spaces
4
Q
in closed circulatory systems blood is pumped from a heart through
A
vessels that return blood to the heart
5
Q
in closed circulatory systems capillaries are the
A
primary structure distinguishing a closed from an open system
6
Q
circulatory fluids are divided into
A
plasma and cellular elements
7
Q
hematocrit is the percent of
A
blood volume occupied by cells
8
Q
plasma is an aqueous medium for transport of ____ ions, gases and ____ solutes
A
inorganic, organic
9
Q
plasma is
-90% ____
-6-8% plasma ____
A
water
proteins
10
Q
in blood
plasma = ___%
buffy coat or wbc=__%
erythrocytes or red blood cells= ____%
A
55%
<1%
45%
11
Q
what do erythrocytes do
A
transport oxygen from lungs or gills to tissues
12
Q
what do erythrocytes contain
A
hemoglobin
13
Q
characteristics of hemoglobin
A
oval shaped in most vertebrates
-BICONCAVE discs without nuclei or organelles in mammals
14
Q
spleen removes old
A
erythrocytes and stores healthy ones, platelets and lympocytes
15
Q
hemopoitec tissues (red bone marrow in birds and mammals) do what
A
generate new erythrocytes (erythropoiesis)
16
Q
what is secreted by the kidneys to stimulate erythropoiesis
A
erythropoiten
17
Q
leukocytes or white blood cells are key components of vertebrate
A
immune systems
18
Q
thrombocytes and platelets are involved in
A
blood clotting
19
Q
thrombocytes are living cells found in all vertebrates except
A
mammals
20
Q
what are cell fragments that circulate in mammalian blood and shed from megakaryocytes in bone marrow
A
platelets
21
Q
what are the 3 steps of hemostasis
A
vascular spasm, formation of platelet plug, blood coagulation
22
Q
what is a vascular spasm
A
immediate constriction of damaged blood vessel slows blood flow through vessel
23
Q
what is this?
-platelets stick to exposed collagen, then to each other
-secrete chemicals that induce vasoconstriction and enhance blood coagulation
A
formation of a platelet plug
24
Q
plasmin dissolves
A
clots
25
plasminogen is produced by the
liver
26
factor xII triggers a cascade of reactions leading to activation of
plasminogen to form plasmin
27
factor xII begins what
the clotting cascade
28
in the intrinsic pathway what begins the cascade and follows
XII-> IX-> VIII
IXa+VIIIa= Xa
29
what is factor IV
ionized calcium
30
what are the 5 pumping mechanisms
flagella, extrinsic muscle or skeletal pumps, peristaltic muscle pumps, chamber muscle pumps, auxillary hearts
31
what are auxillary hearts and why are they important fro insects
like extra hearts near gills or wings
-body parts supported by auxillary hearts need a lot of oxygen and energy
32
what is the heart in arthropods - hint they have open circulatory systems
tubular heart- long tube with muscle
33
what are ostia in arthropods
pore like openings that allow hemolymph to reenter the heart
34
where is the heart located in arthropods
dorsal side- back of body
35
how many chambers does a fish heart have
2-chamber
one atrium one ventricle
36
what is the blood flow in fish hearts
one continuous loop- single circulation system
37
in fish hearts deoxygenated blood from the body enters a collecting chamber called the
sinus venosus
38
in fish hearts after deoxygenated blood enters the sinus venosus, where does it go?
flows into the atrium then pumped to ventricle
39
avian and mammalian hearts have
dual pumps
40
in avians and mammals 2____ receive the blood and 2 ___ pump blood
atria, ventricles
41
what are the two pumps separated by in mammalian and avian hearts
septum
42
the right half pumps oxygen ____ blood into the ___ circulation
depleted, circulatory
43
the left half pumps oxygen___ blood into the _____ system
rich, systemic
44
both sides of mammalian and avian hearts pump equal amounts of
blood
45
heart valves ensure what flow direction of blood
unidirectional- one way
46
right and left atrioventricular valves allow flow from _____ into ____ during ventricular filling
atria, ventricles
47
aortic and pulmonary valves allow flow from _____ into ____ during ventricular contraction
ventricles, arteries
48
thick muscular ____ is sandwiched between endocardium and ____
myocardium, epicardium
49
myocardium consists of interlacing bundles of _____ muscle fibers arranged ____
cardiac, spirally
50
cardiac muscle cells form branching fibers with adjacent cells joined end to end at
intercalated discs
51
what do intercalated discs contain
desmosomes and gap junctions
52
impulses spread to all cells joined by ____ ____ to form a functional synctium
gap junctions
53
the evolution of 2 separate circuits allow for a efficient solution of
high-pressure and low pressure pulmonary circuits
54
what are the 2 types of cardiac cells and how do they differ
myocardial autorythmic cells- myogenic, no true resting potential, SA and AV node, Bundle of His, and perjunke fibers
myocardial contractile cells- have actionpotential similar to neurons or skeletal muscle
55
neurogenic hearts require
external neural stimulus to beat- crustaceans
56
myogenic cells have
pacemaker cells
57
in myogenic hearts membrane of pacemaker cell slowly ____ due to increased ___ current (____ channels), decreased outward __ current, increased inward ___ current( T channels)
depolarizes, Na+, Funny, K+, Ca2+
58
in heart electrical activity, action potential is produced when
L-type Ca2+ channels open at threshold
59
what is the cardiac conduction systems first and second step
1. SA node fires
2. signal from SA reaches AV node and both atria contract simultaneously
60
after SA and AV node contract what occurs
signal slows down through AV node and delays signal to allow ventricles to fill
61
after a signal has been slowed in the AV node what occurs
signal travels quickly through AV bundles and perjunke fibers
62
calcium induced calcium release
influx of calcium releases calcium
🟢 CICR = DHP lets in Ca²⁺ (voltage-gated) → Ca²⁺ binds RyR2 (ligand-gated).
63
depolarization induced calcium release
*🔵 DICR = DHP changes shape (voltage-gated) → physically tugs RyR1 open (mechanically gated).
64
what is the p wave
first hump, atrial depolarization
65
what is the QRS complex
ventricular depolarization and atrial repolarization
66
what is the t wave
last hump- ventricular repolarization
67
in electrocardiogram there is a period of no current flow what does this represent
PR segment represents AV node delay
ST segement represents plateau phase
68
in the plateau phase what occurs
The inward Ca²⁺ current balances the outward K⁺ current, extending duration of action potential
69
what interval represents the start of the T wave and the next p wave
QT interval
70
the cardiac cycle consists of alternating periods of ____ and ____
systole and diastole
71
____ is the period of contraction and emptying
systole
72
_____ is the period of relation and filling
diastole
73
what is the lubb dubb sound
normal heart has 2 heart sounds
74
if the semilunar valves of heart are shut what sound will it make
dubb
75
in long animals such as giraffes why is their blood pressure so high
to pump blood all the way up necks to their brain
76
stroke volume in cardiac output is
how much blood the heart pumps per beat
77
pulse vs heart rate
heart rate- number of times heart contracts in min
pulse- surge of pressure produced by each heartbeat that can be felt
78
what is cardiac output
SVxHR= amount of blood ejected by ventricle
79
to keep cardiac output constant as we age, the heart rate ____ as the stroke volume____
increases, decreases
80
how do chronotropic agents affect cardiac output
heart rate
positive (increases) negative (decreases)
81
how do ionotropic agents affect cardiac output
stroke volume same for positive and negative
82
sympathetic stimulation raises ___ ____ and contraction strength of the myocardium
heart rate
83
parasympathetic (vagus stimulation) lowers heart rate via stimulation of ____ and ___ node
AV and SA
84
increased speed of pacemaker depolarization
increased heart rate
85
epinephrine and norepinephrine ___ ion flow through both funny channels and Ca2+ of pacemaker cells, what does this cause
increase, increase heart rate
86
parasympathetic postganglionic fibers release
Acetylcholine (cholinergic)
87
sympathetic and parasympathetic preganglion fibers release
acetylcholine
88
sympathetic postganglionic fibers release
norepinephrine (adregernic)
89
how is the adrenal medulla a modified sympathetic ganglion
releases epinephrine and norepineprine
90
what three variables govern stroke volume
preload (venous return)
contractility (ionotropic agents)
afterload
91
how are preload and contractility similar
if these increase so does SV
92
what is preload
how much myocardium is stretched
filling balloon more before squeezing
93
what is the frank sterling law of the heart
heart ejects more blood as it receives
94
exercise increases ___ return which increases preload- more blood ___ from the heart
venous, ejected
95
what is contractility or ionotropy
how hard myocardium contracts for a given preload
squeezing balloon harder
96
positive ionotropic agents increase
contractility
97
what is afterload
blood pressure in aorta
-trying to squeeze through a tighter nozzle
98
what are the factors of ventricular failure
low SV, higher preload=dilated ventricle
The heart is filling but failing to eject → classic sign of ventricular (systolic) failure
99
what is intrinsic control in terms of control of stroke volume
direct correlation between SV and end-diastolic volume
-frank starling
100
how does extrinsic control control the stroke volume
sympathetic stimulation enhances contractility of heart
101
the heart recieves its blood supply through the
coronary circulation
102
coronary blood flow ____ during activity
increases
103
the chemical reactions that make life possible occur in what type of solution
aqueous
104
what is this? a compound that dissociates into ions when dissolved in water
electrolyte
105
diffusion is moving water____ its concentration gradient
down
106
if solutes are separated by a selectively permeable membrane water moves from
lower osmolarity to side of higher osmolarity
107
in osmoconformers seawater is ____ in comparison to cells and tissues
isoosmotic
108
most marine and freshwater bony fishes and terrestrial animals are
osmoregulators
109
in osmoregulation seawater is ____ to their tissues
hyperosmotic- more solute than their tissues
110
marine fishes must do what to replace the loss of water out of the gill epithelium
drink a lot of water and then actively pump ions out into the seawater
111
how does a freshwater fish achieve homeostasis
excrete large amount of water in urine and dont drink
112
how do land animals replace loss of water
drinking water or getting it from food
113
excess amino acids and nucleic acids are broken down into
ammonia
114
why is ammonia toxic to cells
it raises the ph
115
birds, reptiles, and terrestrial arthropods convert ammonia to
uric acid
116
mammals and adult amphibians, enzyme catalyzed reactions convert ammonia to less toxix
urea then excrete it in urine
117
in freshwater and marine bony fish, what diffuses right across the gills into surrounding water along the concentration gradient
ammonia
118
how are urea and uric acid similar
high energy cost of synthesis
119
how are urea and ammonia similar
excrete in urine, diffuses across gills or kidneys in mammals
120
ammonia characteristics
requires a lot of water loss but little energy
diluted to nontoxic concentrations
"ammonotely"
121
urea characteristics
more expensive metabolically, less toxic than ammonia, middle ground
122
uric acid characteristics
most expensive metabolically, highly insoluble
123
how do sharks stay isoosmotic to seawater
low ions prevent toxic salt overload
high urea keeps osmotic pressure high without relying on salts
124
since shark blood has less ions than the sea water, what is their mode of excretion if it actively done
low to high in active transport
so from blood to seawater if excreted
125
how do sharks excrete salt
rectal gland secretes concentrated salt solution
126
first step of salt excretion
Na+/K+ ATPase pumps Na+ out of epithelia cells across basolateral into interstitial fluid and K+. in
1. Create the gradient
127
after Na+ is pumped out of epithelial cells into interstitial fluid, what happens next
Na+, 2Cl-, and K+ enter the cell, powered by that Na+ gradient
symport
using gradient to load cell with Cl-
128
after the symport in salt excretion what happens
Cl- exits into the lumen (apical membrane)
-high Cl- in lumen to get excreted
129
after Cl- is moved into the lumen and is negative what happens
Na+ follows
so NaCl secretion into the lumen
130
examples of active transport utilization in salt excretion process
primary active transport- Na+/K+ ATPase on basolateral membrane
Secondary active transport- using that gradient to cotransport Na,K,and 2Cl into cell
131
what is the movement of Na+ K+ and Cl- after cotransporter step
passive.
Cl- exits into lumen after being moved in
Na+ follows Cl-
K+ diffuses into interstitial fluid
132
what is the problem osmoregulation has to fix
loss of electrolytes across their gill epithelium by diffusion
133
in freshwater fish how do they maintain homeostasis
actively transporting ions back into body across gill epithelium
134
in terms of contransporter step in salt excretion, in salt water fishes what side is it on
basolateral side- normal
135
in terms of contransporter step in salt excretion, what side is it on in freshwater
apical side of membrane, they need ions going in instead of out.
136
gas exchange in insets occurs across the membranes of epithelial cells lining the
tracheae
137
the tracheae in insects connects with the atmosphere through openings celled
spiracles, which are a. source of water loss - evaporation
138
what is the adaptation of insects and how they minimized the water loss from spiracles
they close them to minimize the water loss from traheae
139
to maintain homeostasis, insects must carefully regulate the composition of a blood like fluid called hemolymph, what organ do they have to maintain water and electrolyte balance
malpighian tubes
140
malpighian tube location
excretory organ, and the hindgut, and midgut. protruding from the middle of those
141
malpighian tubes have a large ? and are in direct contact with ?
surface area
hemolymph
142
what is responsible for filtration of hemolymph in insects
malpighian tubes
143
epithelial cells in the malpighian tubes contain pumps that actively transport ____ into the lumen of the organ
K+
144
what does the high concentration of K+ in the lumen of insects do
brings water into the tubules by osmosis
145
the filtrate that accumulates in the malpighian tubules flow into the
hindgut where it joins digested food
146
if an insect is osmotically stressed due to a shortage of electrolytes and water, electrolytes and water from the filtrate are ___ in the ____ and returned to the hemolymph
reabsorbed
hindgut
147
what does the reabsorption of water and electrolytes in the hindgut create
hyperosomotic urine, resulting in water conservation and nitrogenous waste elimination
148
in terrestrial insects, what percent of water in filtrate is reabsorbed
80-95%
149
the hindguts ability to recover water from urine is dependent upon what
ion movement, Na+ and K+
150
what are the general principles of insect studies and making concentrated urine
water not pumped directly- moves via osmotic gradients set up by active transport
reabsorption is tightly regulated in response to osmotic stress
151
kidneys occur in ___ and are found where in the body
pairs
back side
152
in terms of kidneys, what brings blood containing nitrogenous wastes into the kidney and what carries the cleaned blood away
brings- renal artery
carries away- renal vein
153
the urine formed in the kidney is transported via a long tube called the
ureter to a storage organ called the bladder
154
from the bladder, urine is transported to the body surface via a tube called th ___
urethra and is then excreted
155
most of the kidneys mass is made up of small structures called
nephrons
156
where are most of the nephrons located
outer region of the kidney called the cortex but some extend into kidneys inner region- medulla
157
what functional characteristics does a nephron share with the insect excratory system
water is not not actively transported- only crosses by osmosis
to move the water, done by gradients set up in interstitial fluid
158
what does the renal corpuscle do
filters blood- forms a filtrate, then sends it to the proximal tubule
159
what does the proximal tubule do
has epithelial cells that reabsorb nutrients, ions, and water from the blood, then send it to the loop of henle
160
what does the loop of henle do
establishes a strong osmotic gradient in interstitial fluid surrounding the loop
161
what does the distal tubule do
reabsorbs ions and water in a way that helps maintain water and electrolyte balance
162
each of the nephrons four regions is associated with
blood vessels
163
what do blood vessels playa key role in
bringing waste-containing blood into nephron and then taking away the molecules that are reabsorbed
164
urine formation begins in the
renal corpuscle
165
what is renal corpuscle made up of
glomerulus and bowmans capsule
166
the glomerulus is a cluster of capillaries that bring
blood to the nephron from the renal artery
167
the bowmans capsule is the region of the nephron that surrounds the
glomerulus
168
filtration is based on size, so what supplies the force to perform filtration
blood pressure, this allows the renal corpuscle to strain large volumes of fluid without expanding energy
169
the filtrate leaves bowmans capsule and enters a convoluted structure called the
proximal tubule
170
the fluid inside the proximal tubule contains water and small solutes such as
urea, glucose, amino acids, vitamins, and electrolytes
171
the epithelial cells of the proximal tubule have a prominent series of small projections called ? that increase?
microvilli, surface area
172
the descending limb is highly ____ to water but almost completely ____ to solutes
permeable, impermeable
173
the ascending limb is highly ____ to Na+ and Cl-, moderately permeable to ___ and almost completely ____ to water
permeable, urea, impermeable
174
so what limb in the loop of henle has the aquaporins
descending
175
when water is leaving the loop of henle in the descending limb, what is the purpose
diluting the blood to make it more concentrated in the loop
176
the fluid inside the nephron ____ Na+ and Cl- in the thin ascending limb
loses
177
the water and salt that move out of the loop diffuse into the
vasa recta
178
what is the vasa recta
the network of blood vessels that runs along the loop, blood vessel
179
the concentration of urea is high in the ____ medulla and low in the ____ medulla
inner, outer
because the innermost section of collecting duct is permeable to urea
180
once filtrate has pass through the loop of henle it enters the
distal tubule
181
changes in the distal tubule and collecting duct are controlled by
hormones
182
if an animal is dehydrated, the brain releases
antidiuretic hormone, ADH
183
what does the hormone aldosterone do
activation of sodium pumps and reabsorption of Na in the distal tubule
184
difference between thick and thin ascending limb
thick ascending uses active transport
185
if ADH is present, water leaves the filtrate, produces ___ volume of urine that is ____ to blood
small, hyperosmotic
