chapter 42 - circulation and gas exchange Flashcards
(146 cards)
1
Q
small molecules can move between cells andtheir surroundings by (spell)
A
diffusion; only efficient over small distances
2
Q
in most animals, cells exchange materials with the environment via a _______ _____ ______ ______
A
fluid-filled circulatory system
3
Q
- function in the digestion and distribution of substances throughout the body
- helpful in animals that don’t have a circulatory system (cnidarians, flatworms)
A
gastrovascular cavities
4
Q
in insects, other arthropods, and some molluscs, circulatory fluid called _________ bathes the organs directly in an open circulatory system (spell)
A
hemolymph
5
Q
in a closed circulatory system, _______ is confined to vessels and is distinct from the interstitial fluid (spell)
A
blood
6
Q
a muscular pump (spell)
A
heart
7
Q
what does circulatory system consist of?
A
circulatory fluid, set of interconnecting vessels, and a muscular pump
8
Q
what are the three types of blood vessels
A
arteries, veins, capillaries
9
Q
branch into arterioles and carry blood away from the heart to capillaries (spell)
A
arteries
10
Q
heart chamber that pumps blood out of the heart (spell)
A
ventricle
11
Q
microscopic blood vessel that penetrates the tissues and consists of a single layer of endothelial cells that allows exchange between the blood and interstitial fluid
A
capillary
12
Q
vessel that conveys blood between a capillary bed and a vein (spell)
A
venule
13
Q
network of capillaries in a tissue or organ (spell)
A
capillary bed
14
Q
chamber of the vertebrate heart that receives blood from the veins and transfers blood to a ventricle (spell)
A
atria
15
Q
blood enters through ____ and pumped out through ____ (spell)
A
atria, ventricles
16
Q
blood leaving the heart passes through two capillary beds before returning(spell)
A
single circulation
17
Q
separate pulmonary and systemic circuits, in which blood passes through the heart after completing each circuit (spell)
A
double circulation; amphibians, reptiles and mammals
18
Q
reptiles and mammals double circulation
A
- O2 poor blood flows through pulmonary circuit to get O2 from lungs
19
Q
infolded respiratory surface of a terrestrial vertebrate,
land snail, or spider that connects to the atmosphere by narrow tubes (spell)
A
lung
20
Q
amphibians double circulation
A
- O2 poor blood flows through pulmocutaneous circuit to pick up O2 using lungs/skin
21
Q
branch of the circulatory system that supplies
oxygenated blood to and carries deoxygenated blood away from organs and tissues throughout the body (spell)
A
systemic (entire body) circuit
22
Q
double circulation blood mixing
A
doesn’t mix in reptiles and mammals, does in amphibians
23
Q
respiratory pattern where breathing is not continuous, involving periods of apnea between bursts of ventilation (spell)
A
intermittent breathing
24
Q
turtles, snakes, lizards heart
A
2 atria + 1 ventricle, divided by incomplete septum
25
alligators and other crocodilians, a septum divides....
the ventricles, pulmonary and systemic circuits connect where arteries exit in the heart
26
mammals and birds heart
- 4-chambered heart w/ 2 atria and 2 ventricles
- left side pumps/receive O2 rich blood
- right side receive/pumps O2 poor blood
27
oxygen-rich blood returns from lungs via pulmonary veins to...
left atrium of heart
28
blood leaves the left ventricle via...
the aorta
29
oxygen-rich blood flows into the left ventricle and is pumped out to...
tissues via systemic circuit
30
when right ventricle contracts blood is pumped to...
lungs via pulmanory arteries; flows through capillary beds in the left and right lungs, loads + unloads CO2
31
O2 diffuses from _____ to _____, CO2 diffuses from ______ to ______
blood to tissues, tissues to blood
32
what kind of walls do the 2 atria have?
thin walls, collection chambers for blood returning
33
what kind of walls do the 2 ventricles have?
thick walls, contract forcefully
34
rhythmic cycle of heart contracting and relaxing (spell)
cardiac cycle
35
contraction/pumping phase (spell)
systole
36
relaxation/filling phase (spell)
diastole
37
O2 poor blood from the head, neck, and forelimbs is channeled into the...
superior vena cava
38
drains blood from the trunk and hind limbs...
inferior vena cava
39
the amount of blood pumped in a single contraction (spell)
stroke volume
40
vol/min of blood pumped (spell)
cardiac output
41
number of beats/min (spell)
heart rate
42
what are the 4 valves that prevent backflow of blood
atrioventricular valves, semilunar valves
43
valves that separate each atrium and ventricle; located at each exit of the heart, where the aorta
leaves the left ventricle and the pulmonary artery leaves the right ventricle(spell)
atrioventricular valves
44
- valves that control blood flow to the aorta and the pulmonary artery (spell)
- prevents a backflow of blood when the ventricle
contracts
semilunar valves
45
backflow of blood through a defective valve causes a .... (spell)
heart murmur
46
pacemaker that sets the rate and timing at which cardiac muscle cells contract (spell)
sinoatrial (SA) node; controls heart rate
47
impulses that travel during the cardiac cycle can be recorded as an...
electrocardiogram (ECG or EKG)
48
increased heart rate
tachycardia
49
bradycardia
decreased heart rate
50
what are autorhtymic cardiac muscle cells?
cells that contract without any signal from the nervous system
51
impulses from the SA node travel to the...
AV node; where impulses are deyaed and travel to Purkinje fibers
52
region of specialized heart muscle tissue between the
left and right atria where electrical impulses are delayed for about 0.1 second before spreading to both ventricles and causing them to contract
atrioventricular node
53
Purkinje fibers make the...
ventricles contract
54
sympathetic division ___ ____ pacemaker
speeds up
55
parasympathetic division ____ ____ the pacemaker
slows down (normal rate is about 70 BPM)
56
tissue which forms a single layer of cells lining central lumen of blood vessels (spell)
endothelium
57
capillaries function and structure
- thin walls + endothelium and basal lamina
- facilitate exchange of material
58
arteries function and structure
- endothelium, smooth muscle, connective tissue
- thick elastic walls to accommodate high pressure of blood pumped from heart
59
veins function and structure
- endothelium, smooth muscle, connective tissue
- veins have valves to maintain unidirectional blood flow
- carry blood back to the heart
60
velocity of blood flow is slowest in the...
capillary, high resistance + big cross-sectional area, necessary for exchange of materials
61
blood flows from areas of higher pressure to areas of...
lower pressure
62
the further you are from the heart...
the lower the blood pressure in that area
63
the pressure in the arteries during ventricular systole; it is the highest pressure in the arteries (spell)
systolic pressure; 140-90
64
the rhythmic bulging of artery walls with each heartbeat (spell)
pulse
65
the pressure in the arteries during diastole; it is lower than systolic pressure (spell)
diastolic pressure; 60-90
66
decrease in the diameter of blood vessels caused; contraction of smooth muscle in arteriole walls, increases bp (spell)
vasoconstriction
67
increase in the diameter of blood vessels; relaxation of smooth muscles in the arterioles; causes bp to fall (spell)
vasodilation
68
which gas is a major inducer of vasodilation?
nitric oxide (NO)
69
which peptide is a potent inducer of vasoconstriction ?
endothelin
70
gravity + BP
- significant impact
- measure at the same height as your heart
- normal 120/70 mm Hg
71
is caused by inadequate blood flow to the head
fainting
72
what mechanisms regulate distribution of blood in capillary beds
- constriction/dilation of arterioles that supply capillary beds
- precapillary sphincters that control flow of blood between arterioles + venules
73
vessel that conveys blood between an artery and a
capillary bed (spell)
arteriole
74
uptake of molecular oxygen from the environment
and the discharge of carbon dioxide to the environment (spell)
gas exchange
75
_____ _____ returns fluid that leaks out from capillary beds (spell)
lymphatic system
76
what is the fluid lost by capillaries called? (spell)
lymph
77
swelling caused by disruptions in the flow of lymph
edema
78
organs that filter lymph and contain cells that attack viruses and bacteria (spell)
lymph nodes (swollen and tender when body fighting infection)
79
blood is suspended in a liquid matrix called _____ (spell)
plasma; 55% of volume of blood
80
45% of volume of blood are...
erythrocytes (RBC) and leukocytes (WBC), megakaryoocyte form platelets
81
what does plasma consist of?
electrolytes
82
plasma functions
- proteins influence blood pH + maintain osmotic balance between blood and interstitial flood
- blood clotting, lipid transport, immunity
83
leukocytes function in...
defense
84
erythrocytes transport...
O2
85
the iron-containing protein that transports O2 (spell)
hemoglobin; found in RBC
86
mature RBC lack...
nuclei & mitochondria
87
fragments of cells used in clotting (spell)
platelets
88
disease caused by abnormal hemoglobin proteins that forms aggregates (spell)
sickle-cell disease (SSD)
89
undifferentiated cells with the unique ability to self-renew and differentiate into various specialized cell types (spell)
stem cells; red, white blood cells and platelets all develop from them
90
which hormone stimulates erythrocyte production when O2 delivery is low? (spell)
erythropoietin
91
blood clot formed within a blood vessel, can block blood flow (spell)
thrombus
92
in coagulation, reactions convert...
inactive fibrinogen to fibrin, forming clot
93
cardiovascular disease caused by buildup of fatty deposits within arteries (spell)
atherosclerosis
94
delivers cholesterol to cells for membrane production (spell)
low-density lipoprotein (LDL)
95
scavenges excess cholesterol for return to the liver (spell)
high-density lipoprotein (HDL)
96
the damage or death of cardiac muscle tissue resulting from blockage of one or more coronary arteries (spell)
heart attack, myocardial infarction
97
is the death of nervous tissue in the brain, resulting from rupture/blockage of arteries in the head (spell)
stroke
98
is chest pain caused by partial blockage of the coronary arteries (spell)
angina pectoris
99
high blood pressure (spell)
hypertension; contributes to heart attack and stroke; can be controlled by diet, exercise, medication
100
how would proportion LDL relative to HDL can be decreased?
- diet, exercise, not smoking
- statins drugs to reduce LDL levels
101
inflammation and thrombus formation
- plays a role in atherosclerosis
- aspirin inhibits inflammation so also reduces risk
102
the uptake of O2 from the environment and the discharge of CO2 to the environment (spell)
gas exchange
103
the pressure exerted by a particular gas in a mixture of gases (spell)
partial pressure; air we breathe
104
does obtaining O2 from water or air require greater effiiciency?
water; gas exchange takes place by diffusion
105
gills in aquatic animals
- outfoldings of body that create a large surface area for gas exchange (fish)
106
moves the respiratory medium over the respiratory surface (spell)
ventilation
107
blood flows in the opposite direction to water passing over the gills (spell)
countercurrent exchange system; fish
108
consists of a network of branching tubes throughout the body in insects; air filled tubes that carry O2 directly to cells (spell)
tracheal system
109
how does tracheal system work?
- tracheal tubes supply O2 directly to body cells
- respiratory and circulatory very separate
110
which organ directs air to the lungs and food to the stomach?
pharynx
111
mammalian respiratory systems
- branching ducts convey air to lungs
- air inhaled is filtered, warmed, humidified, sampled for odors
112
also known as the voice box, is an organ in the upper neck responsible for breathing, swallowing, and producing sound (spell)
larynx
113
route of air to lungs
nose/mouth, pharynx, larynx, trachea, bronchi, bronchioles, alevoli
114
tiny air sacs sacs at the tips of bronchioles; gas exchange occurs in a mammalian lung(spell)
alveoli; alveolus
115
one of a pair of breathing tubes that branch from the
trachea into the lungs (spell)
bronchus
116
fine branch of the bronchi that transports air to alveoli (spell)
bronchiole
117
secretions called ________ coat the surface of the alveoli (spell)
surfactants; prevent alveoli from collapsing and sticking to themselves
118
the alternate inhalation and exhalation of air; ventilates the lungs (spell)
breathing
119
amphibian such as a frog ventilates its lungs by ______, which forces air down the trachea (spell)
positive pressure breathing
120
ventilation in birds
- air sacs to keep air flowing
- passes through lungs in one direction only
- 2 cycles of inhalation and exhalation
121
system that pulls air into the lungs (spell)
negative pressure breathing; mammals
122
maximum tidal volume; maximum volume of air that a mammal can inhale and exhale with each breath (spell)
vital capacity
123
the volume of air inhaled with each breath (spell)
tidal volume
124
air that remains in the lungs after exhalation (spell)
residual volume
125
its contraction increases the volume of the thorax and so inflates the lungs (spell)
diaphragm
126
breathing control center in humans
- medulla, medulla obloganta
- regulates rate and depth of breathing in response to pH changes
127
what monitors O2 and CO2 concentrations in the blood?
- sensors in aorta and carotid arteries
- signal breathing control centers to respond
128
proteins that transport oxygen, greatly increase the amount of oxygen that blood can carry; in blood or hemolymph (spell)
respiratory pigments
129
in vertebrates, hemoglobin is contained within...
erythrocytes
130
CO2 produced during cellular respiration lowers blood pH and decreases the affinity of hemoglobin for O2 (spell)
Bohr shift
131
how many molecules of O2 can one hemoglobin molecule carry?
four molecules of O2, one for each iron-containing heme group
132
CO2 transport in blood
1. bicarbonate ions, 70%
2. bound to hemoglobin (carry 2), 20%
3. dissolved in plasma as CO2 (10%)
133
diving mammals
- weddell seals in Antarctica can stay underwater for 20 mins-1hr
- cuvier's beaked whale can dive to 2900 m and stay there for 2+ hrs
134
diving mammals adaptations
- high blood to body volume ratio
- use O2 slowly
- store O2 in muscles + myoglobin proteins
135
how do diving mammals conserve O2?
- changing buoyancy to glide passively
- routing blood to vital tissues
- deriving ATP in muscles from fermentation once O2 depleted
136
O2 storing, pigmented protein in muscle cells (spell)
myoglobin
137
drop of blood flow
Right Atrium
→ Right Ventricle
→ Pulmonary Arteries (to lungs)
→ Lungs (gas exchange: gains O₂, loses CO₂)
→ Pulmonary Veins
→ Left Atrium
→ Left Ventricle
→ Aorta
→ Body tissues (delivers O₂)
→ Vena Cava (superior/inferior)
→ Back to Right Atrium
138
how much blood flows through capillaries at any one time?
5–10% of total capillaries are open at a time — controlled by precapillary sphincters based on tissue need.
139
how does blood pressure relate to osmotic pressure in capillaries?
- BP pushes fluid out of capillaries
- osmotic pressure pulls fluid in (due to plasma proteins)
- balance of both determines net movement of fluid
140
141
142
143
describe the blood clotting process
Platelets plug the injury (physical)
Clotting factors activate → fibrin net forms (chemical)
Requires calcium, proteins, and a cascade of reactions
144
blood color in spiders
- blue
- pigment hemocyanin
145
blood color in some worms and leeches
- green
- chlorocruorin
146
blood color in marine worms, peanut worms, penis worms, brachipods
- purple
- hemyrethyrin
