Circulation Flashcards

(84 cards)

1
Q

What do unicellular organisms use to exchange material with their environment directly

A

diffusion

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

when is diffusion efficient

A

small distances

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

How do protosomes exchange material with their environment

A

through diffusion, they live in aquatic environments with thin body walls

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

what do gastrovascular cavities do

A

minimize diffusion distances for digestion and circulation

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

what are the three components of a CS

A

circulatory fluid, interconnecting vessels, muscular pump

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

what are the two types of CS

A

open and closed

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

what does a CS do?

A

connects fluid that surrounds cells with organs that exchange gases, nutrients, wastes

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

What are open Cs

A

no distinction between blood and IF (hemolymph)

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

What organisms have open systems

A

insects, arthropods, molluscs

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

what are some characteristics in an open CS

A

internal fluid is circulated through body cavity, pressure rapidly dissipates (requires a faster heart rate or accessory hearts)

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

what is a closed Cs

A

blood is confined to vessels and is distinct from IF

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

where do substances move between in a closed CS

A

blood —> IF, IF —> cells

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

what is a key characteristic of closed CS

A

more efficient at transport (maintain pressure gradients)

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

What are arteries

A

carry blood away from the heart to capillaries

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

what are veins

A

return blood from capillaries to heart

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

what are capillary beds and their function

A

networks of capillaries, sites of chemical exchange between blood and IF

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

What animals use single circulation, how many heart chambers do they have?

A

fish, rays, sharks, two or more chambers

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

Single circulation pathway

A

Atrium, Ventricle, Gill capillary beds, Body capillary beds

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

what is a disadvantage of single circulatio

A

low pressure, no fresh perfusion to the heart

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

How many chambers do amphibian hearts have

A

3, 2 atria and 1 ventricle

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

what is the pathway of double circulation in amphibians

A

the ventricle pumps blood into a forked artery that goes into the pulmonary and systemic circuit

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

what can amphibians do to their bloodflow

A

can shut off the blood flow to lungs when underwater

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

how many heart chambers do mammals and birds have

A

four (2 atria, 2 ventricles)

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

What is the function of the systemic circuit

A

carries oxygen rich blood from heart to the rest of the body

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
what is the pulmonary circuit
where blood travels between heart and lungs
26
why do mammals and birds require more oxygen
because they are endotherms (regulate body temp) and therefore have higher metabolic rates
27
what is cardiac output
the volume of blood pumped into systemic circuit per minute
28
what does cardiac output depend on
heart rate and stroke volume (amount of blood pumped in a single contraction)
29
do larger or smaller animals have a faster heart rate, why?
smaller, mass-specific metabolic rates
30
pulmonary artery function
brings de-oxygenated blood from right ventricle to lungs
31
pulmonary veins function
return oxygenated blood to left atrium from lungs
32
aorta function
distribute oxygenated blood through the body from the left ventricle
33
superior and inferior vena cava function
bring de-oxygenated blood back to the right atrium
34
atria structure and function
thin walls, collect chambers for blood returning to the heart
35
ventricles structure and function
thick walls (contract more forcefully), eject blood to distal sites
36
What is the heart wall made of?
Muscle (myocardium) encapsulated between inner lining (endocardium) and a fibrous protective sheath (pericardium)
37
What is the function of the AV valves and where are they located?
control blood flow within the heart, between the atria and ventricles
38
SL valve function
control cardiac output via the aortic and pulmonary arteries
39
what causes a heart murmer
backflow of blood through a defective valve
40
what is the systole phase
contraction or pumping
41
what is the diastole phase
filling or relaxation
42
what is the first step of the cardiac cycle
heart = relaxed, atria fill with blood, valves closed, AV valves pushed open and ventricles begin to fill
43
what is the second step of the cardiac cycle
atria contract and fully fill ventricles once they fill 80% of the way
44
what is the third stage of the cardiac cycle
ventricles begin to contract, force AV valves closed, as contraction builds SL valves open
45
how is the cardiac cycle coordinated?
muscle cells are autorhythmic
46
what is the SA nodes function
sets the rate and timing at which cardiac muscle cells contract
47
impulse pathway from the SA node
SA ---> AV (impulses delayed) ---> purkinje fibers (ventricles contract)
48
what regulated the pacemaker
NS: para and sympathetic
49
how does each division of the NS impact the pacemaker
Sympathetic = speeds up (adrenaline) Para = slows down (acetylcholine)
50
what also regulates the pacemaker
hormones and temperature
51
what do barorecptors do and where are they located
in the heart muscle, aorta and carotid arteries (supply blood to brain), provide blood pressure information to the medulla
52
vein structure, how does blood flow
thin walls, flows to heart via gravity and muscle action
53
arteries structure
thick walls, accommodate high blood pressure of blood pumped from the heart
54
what are three components of arteries and veins
endothelium, smooth muscle, connective tissue
55
what is the endothelium made of and its function
the epithelial layer that lines blood vessels, minimizes resistance
56
what is a vessels cavity called
the central lumen
57
how is backflow prevented in veins
one-way valves
58
how is blood moved through veins
smooth, skeletal muscle contraction and the expansion of the vena cava with inhalation
59
components of capillaries
thin walls, endothelium, basal lamina to facilitate exchange
60
systolic pressure
pressure in arteries during ventricle systole, high pressure
61
diastolic pressure
pressure in arteries during diastole
62
what is the pulse
rhythmic bulging of artery walls with each heartbeat
63
what dissipates pressure in capillaries and arterioles
resistance to blood flow in the narrow diameter
64
where is blood flow slowest and why
capillary beds, high resistance due to large surface area, slow exchange of materials
65
where does exchange between blood and IF take place in capillaries
endothelial walls
66
what drives out fluid from the capillaries
difference between blood and osmotic pressures
67
what is the function of the lymphatic system
returns fluid that leaks out from the capillary beds
68
what are lymph nodes functions
filter lymph and have role in defense
69
what regulates the distribution of blood in capillary beds
constriction/dilation of arterioles and pre-capillary sphincters between arterioles and venules
70
how does vasoconstriction and vasodilation affect blood pressure
constriction increases, dilation decreases
71
what are inducers of vasodilation/constricton (one each)
dilation = nitric oxide, constriction = peptide endothelin
72
what is plasma made of
water, inorganic salts (electrolytes0 and proteins
73
what is the functions of proteins in blood (4)
influence blood pH, help maintain osmotic balance between blood and IF, lipid transport and clotting
74
what are suspended in plasma
erthrocytes, leukocytes, platelets
75
where do blood cells develop from
stem cells in red marrow of bones
76
what does EPO do
stimulate erythrocyte production when O2 delivery is low, can treat anemia
77
what are the two main types of stem cells
lymphoid and myeloid
78
what do erythrocytes contain, what is their structure
packed with hemoglobin, lack nuclei and mitochondria
79
what is the function of leukocytes
defense either through phagocytizing bacteria and debris or by mounting immune responses against foreign substances
80
what are platelets
fragments of bone marrow cells
81
platelet function
blood clotting
82
how are platelets activated
exposed collagen fibers or by thrombin, once activated change shape and form plug and release clotting factors
83
what is coagulation
formation of a solid clot from blood, fibrin mesh
84
what is a blood clot in a blood vessel called, why is it dangerous
a thrombus, can block blood flow