circulatory system #3 Flashcards
(109 cards)
1
Q
what is stroke volume?
A
the amount of blood forced out of the heart with each beat (mL/beat)
2
Q
what is the average stroke volume?
A
70mL/beat
3
Q
what does a larger stroke volume mean?
A
a stronger heart
4
Q
what is cardiac output?
A
the amount of blood pumped by the heart per minute
5
Q
how do you calculate cardiac output?
A
heart rate x stroke volume = cardiac output
6
Q
what is the average cardiac output?
A
4900mL/min
7
Q
what does your cardiac output depend on?
A
- the strength of your heart
- your size
- your age
8
Q
how does size affect cardiac output?
A
the smaller you are, the less blood you have, less blood pumped per minute
9
Q
how does age affect cardiac output?
A
as you get older, heart rate decreases, therefore cardiac output decreases
10
Q
how can you change cardiac output?
A
- exercise - temporary change in HR
- age - due to decrease in HR
11
Q
what factors affect blood pressure?
A
- eating
- caffeine
- nicotine
- high altitudes
- stress
- atherosclerosis (plaque on artery walls)
- exercise
12
Q
what is myocardial infarction?
A
interruption of blood supply to the heart (clot in an artery)
13
Q
what is an aneurysm?
A
abnormal ballooning of an artery
14
Q
what is a stroke?
A
loss of blood flow to a part of the brain - brain can’t get enough oxygen
15
Q
what are congenital heart defects?
A
defects in the structure of the heart or great vessel, present at birth
16
Q
what are the two components of blood?
A
- plasma
- blood cells
17
Q
how much of blood is made up of plasma?
A
55%
18
Q
how much of blood is made up of blood cells?
A
45%
19
Q
what are the characteristics of plasma?
A
- slightly basic
- yellow colour
- 90% water
- organic substances (proteins, carbs, etc)
- CO2 and O2
- hormones and minerals
20
Q
what % of plasma is water?
A
90%
21
Q
what are the 3 types of blood cells?
A
- erythrocytes (red blood cells)
- leukocytes (white blood cells)
- thrombocytes (platelets)
22
Q
what are erythrocytes?
A
red blood cells
23
Q
what % of blood volume do erythrocytes make up?
A
44%
24
Q
where do erythrocytes originate?
A
bone marrow
25
what is the main function of erythrocytes?
to carry oxygen throughout the body - 20 secs to circulate
26
what are the characteristics of erythrocytes?
- lack cell nucleus (enucleated)
| - bi-concave structure (increases surface area)
27
what is the life span of erythrocytes?
100-120 days
28
what molecule does red blood cell contain?
hemoglobin
29
what is hemoglobin?
a molecule with iron for carrying oxygen
30
how many hemoglobin per RBC?
280 million/RBC
31
what is erythropoiesis?
the process of producing RBCs
32
what is the process of producing RBCs called?
erythropoiesis
33
how many RBCs can bone marrow produce per second?
2.2 million/sec
34
what determines RBC production?
determined by the amount of O2 available
35
what happens when oxygen levels are low?
kidneys secrete erythropoietin (hormone) which stimulates the bone marrow to produce RBCs
36
what happens to our oxygen levels after we donate blood or are at a high altitude?
it lowers
37
what does the spleen do?
- stores extra RBCs for emergencies
| - filters blood and destroys worn out RBCs
38
what % of blood volume do leukocytes make up?
they make up <1% of blood volume
39
what are leukocytes?
white blood cells
40
where do leukocytes originate?
the bone marrow and thymus gland
41
what is the ratio of WBCs to RBCs?
1:700
42
what are the two categories of leukocytes?
1. granulocytes
| 2. agranulocytes
43
what are the three types of granulocytes?
- neutrophil
- eosinophil
- basophil
44
what are the types of agranulocytes?
- lymphocytes
| - monocytes
45
what do lymphocytes and monocytes evolve into?
macrophages
46
what is the function of lymphocytes?
antibody production
47
what is the function of macrophages?
phagocytosis
48
what is the function of neutrophils?
phagocytosis
49
what do neutrophils look like?
they are multi lobed nucleus
50
what do lymphocytes look like?
large round nucleus
51
what do monocytes look like?
C-shaped nucleus
52
what are thrombocytes?
- platelets
- tiny cell fragments from the bone marrow
- they have no nucleus and they breakdown quickly
53
what is the main function of a thrombocyte?
blood clotting to prevent blood loss
54
what attracts platelets when an injury occurs?
collagen fibres attract platelets like a magnet when they are exposed to the bloodstream
55
what is the blood clotting procedure?
- when platelets arrive at an injury, they rupture and release a protein called thromboplastin
- thromboplastin combines with calcium and activates a protein called prothrombin
- thrombin reacts with fibrinogen to form fibrin
- fibrin then forms a mesh of fibres to clot and close a wound
56
is fibrin soluble?
no
57
what Is thermoregulation?
keeping the temperature of the body within a range that allows cells to function normally
58
what is body temp regulated by?
the brain
59
what is the average core temp of a human?
~37 degrees celcius
60
what controls heat loss?
the nervous system, blood vessels near the skin surface can dilate or constrict to control heat loss
61
how does vasodilation affect body temp?
increases heat loss
62
how does vasoconstriction affect body temp?
decreases heat loss (conserves heat)
63
what part of the brain is responsible for monitoring body temp?
the hypothalamus
64
what happens when your body temp is too high?
- blood vessels near skin surface dilate
| - sweating begins to cool the body
65
what happens when your body temperature is too cold?
- vessels constrict to limit blood flow to extremities
- hairs on arm raise to trap warm air (goosebumps)
- shivering begins (quick contractions of skeletal muscles)
66
what are antigens?
- the markers that classify a person's blood type
- they are a cell's ID
- they are inherited
67
what are antibodies?
- Y-shaped proteins created by your body that bind to specific antigens
- they bind to foreign antigens to disable them
- specifically designed to target forge in invaders
68
where are antibodies found?
in the plasma
69
what are the two antigen systems?
1. ABO system
| 2. Rh system
70
what are the two inherited antigens?
A and B
71
what do RBC antigens form?
naturally occurring complimentary antibodies
72
what is agglutination?
- aka. clumping
| - occurs if blood types are not compatible - can be deadly
73
what are blood donations?
donating whole blood, but it is then separated into its parts (WBCs, RBCs, and plasma)
74
what are blood transfusions?
the transfer of only the blood cells, not the plasma, from one person to another
75
what is a universal donor?
blood type -O is the universal donor because it doesn't contain any antigens
76
can antibodies be transfused?
no
77
what is a universal recipient?
blood type AB+ is the universal recipient because it's plasma doesn't contain any antibodies
78
what happens if the wrong blood type is transfused?
agglutination (clumping) will occur because the body will reject the antigens and form antibodies against them
79
what is the Rh system?
a system separate from the ABO system, it is another set of antigens found on most blood cells
80
what is hemolytic disease of newborns?
this is when a mother is Rh- and has one Rh+ baby, during birth she develops anti-Rh antibodies, so if she has another Rh+ baby, her antibodies will attack the baby's red blood cells, possibly killing it
81
what is anemia?
reduced red blood cells
82
what is hemophilia?
insufficient clotting protein inherited
83
what is leukaemia?
cancer of the white blood cell
84
what is the lymphatic system?
a network of ducts and nodes containing lymph that runs parallel too to blood vessels
85
what is lymph?
pale yellow - colourless fluid
86
what are lymph nodes?
nodes located around the body that store lymphocytes (filter lymph)
87
what happens when lymph nodes are working extra hard?
they swell
88
what is the function of the lymphatic system?
- to collect lymph
- to maintain fluid balance through subclavian ducts
- fat transportation through intestinal villi
- to aid in immunity
89
how does the lymphatic system aid with immunity?
- WBC mature in lymph nodes
| - lymph vessels also contain macrophages
90
what are the lymphatic organs?
- thymus gland, spleen, lymph nodes, bone marrow
| - they all help to create leukocytes
91
which lines of defence in the immune system are specific/nonspecific?
- 1st and 2nd are non specific
| - 3rd is specific
92
what is the first defence?
barriers
93
what are the barriers of the first defence?
- skin (keratinized and acidic)
- mucus (traps particles)
- cilia (catch particles)
- saliva + tears (contain enzymes)
- acidic stomach (destroys foreign substances)
94
what is the second defence?
inflammatory response (cell mediated immunity)
95
what happens during the second defence?
- macrophages and neutrophils (phagocytes) are activated
- damaged tissues release histamine
- histamine causes capillaries to swell and leak - releasing phagocytes
- phagocytes then "eat" any bacteria and dead debris in infected tissue
96
what is the third defence?
7-step immune response (antibody mediated immunity)
97
what are the two main types of lymphocytes?
T-lymphocytes and B-lymphocytes
98
where do B-cells mature?
in the Bone marrow
99
where do T-cells mature?
in the Thymus
100
what are the two types of B-cells?
Plasma B and Memory B
101
what are the four types of T-cells?
Helper T, Killer T, Suppressor T and Memory T
102
what are plasma B-cells?
- they make antibodies that match the foreign invaders
| - binding of the antibody to the antigen results in disabling of the antigen
103
what are memory B-cells?
remember the invaders for next time so that antibodies are made sooner in response
104
what are helper T-cells?
recognize antigens and give off chemical signals that stimulate macrophages, B-cells and other T-cells
105
what are killer T-cells?
attaches itself to damaged cells, releases toxins to split the cell thereby killing the invader and itself
106
what are suppressor T-cells?
slow/turn off immune response to protect healthy tissues after invader is killed off
107
what are memory T-cells?
remain in the bloodstream after immune response is shut down, if antigen is encountered again it will start immune response quickly (like memory B)
108
what is the process of the 3rd defence?
1: monocytes identify foreign cells
2: monocyte changes into macrophage, adheres to organism and slowly eats it
3: macrophage places intruders antigens on its outer membrane - this alarms other cells
4: helper T-cells make copy of antigen, activate plasma B cells and killer T cells
5: plasma B cells divide rapidly and also make antibodies that correspond to antigen
6: antibodies attach to antigen (antigen-antibody complex), dump together, easier for the macrophages to find and destroy cells
7: when invasion is under control, suppressor T cells shut off the immune response
109
what is the antigen- antibody complex?
what is is called when antibodies attach to antigen
