1
00:00:01,491 --> 00:00:05,658
- [Instructor] In this chapter
we'll be looking at blood.

2
00:00:06,536 --> 00:00:09,587
So, let's start off with
the circulatory system.

3
00:00:09,587 --> 00:00:12,424
First things first, you bring in oxygen

4
00:00:12,424 --> 00:00:15,065
and eliminate carbon dioxide.

5
00:00:15,065 --> 00:00:17,823
That's what the respiratory
system is used for;

6
00:00:17,823 --> 00:00:19,490
the exchange of gas.

7
00:00:20,770 --> 00:00:23,472
But that gas exchange has to be coupled

8
00:00:23,472 --> 00:00:26,198
with the circulatory system

9
00:00:26,198 --> 00:00:29,946
because your blood is
going to move the oxygen.

10
00:00:29,946 --> 00:00:34,259
It's going to move the carbon
dioxide through your body.

11
00:00:34,259 --> 00:00:35,856
So it's taking it to
every cell in your body

12
00:00:35,856 --> 00:00:38,189
from your head to your toes.

13
00:00:39,366 --> 00:00:40,992
But you also need to make sure the

14
00:00:40,992 --> 00:00:45,874
circulatory system integrates
with the urinary system.

15
00:00:45,874 --> 00:00:48,124
Because the urinary system is going

16
00:00:48,124 --> 00:00:51,653
to be getting rid of liquid waste.

17
00:00:51,653 --> 00:00:56,055
Well liquid waste is going to
be excess fluid, excess water.

18
00:00:56,055 --> 00:00:58,571
But also extra salts you don't need,

19
00:00:58,571 --> 00:01:02,340
metabolic waste, anything
the body has in excess

20
00:01:02,340 --> 00:01:05,173
that can be dissolved in a liquid.

21
00:01:07,498 --> 00:01:10,884
Now we also have the digestive system.

22
00:01:10,884 --> 00:01:13,199
You somehow have to get your nutrients.

23
00:01:13,199 --> 00:01:15,493
So you're eating, you're drinking liquids.

24
00:01:15,493 --> 00:01:17,530
It goes down your GI tract.

25
00:01:17,530 --> 00:01:19,109
So we're talking down in the stomach,

26
00:01:19,109 --> 00:01:20,575
down in the intestines.

27
00:01:20,575 --> 00:01:24,460
Down in the intestines you're
going to absorb the nutrients,

28
00:01:24,460 --> 00:01:27,322
absorb the different
salts, absorb the water,

29
00:01:27,322 --> 00:01:30,822
it all is put into the circulatory system.

30
00:01:32,995 --> 00:01:34,384
Eventually, what's not absorbed

31
00:01:34,384 --> 00:01:36,573
and what has some extra waste put in there

32
00:01:36,573 --> 00:01:38,981
will be eliminated from the body.

33
00:01:38,981 --> 00:01:41,811
But it just shows that this
circulatory system must

34
00:01:41,811 --> 00:01:46,119
integrate with at least these
three other systems directly.

35
00:01:46,119 --> 00:01:49,536
Digestive, Respiratory, and Urinary.

36
00:01:51,071 --> 00:01:53,471
So the main three functions of blood

37
00:01:53,471 --> 00:01:57,417
and there's more than
these three functions.

38
00:01:57,417 --> 00:02:01,192
These are just the
three primary functions.

39
00:02:01,192 --> 00:02:04,649
Probably the first and
foremost is transportation.

40
00:02:04,649 --> 00:02:07,905
It allows you to transport your nutrients.

41
00:02:07,905 --> 00:02:09,421
Things like your carbohydrates,

42
00:02:09,421 --> 00:02:10,588
your proteins,

43
00:02:11,773 --> 00:02:13,356
some of the lipids.

44
00:02:15,298 --> 00:02:19,968
It allows you to transport
some vitamins, some minerals.

45
00:02:19,968 --> 00:02:23,468
It's also allowing the transport of waste.

46
00:02:24,532 --> 00:02:26,748
Now waste isn't necessarily
something that's bad,

47
00:02:26,748 --> 00:02:30,347
it could just be that you
have too much of something.

48
00:02:30,347 --> 00:02:32,850
For example, if you have too much salt,

49
00:02:32,850 --> 00:02:35,275
sodium chloride in your blood,

50
00:02:35,275 --> 00:02:37,208
you're going to need to get rid of it.

51
00:02:37,208 --> 00:02:40,041
That is like a waste product.

52
00:02:40,041 --> 00:02:40,874
Hormones.

53
00:02:42,220 --> 00:02:43,388
Well, hormones can be anything from

54
00:02:43,388 --> 00:02:47,479
growth hormone which
helps you grow, obviously,

55
00:02:47,479 --> 00:02:49,650
to more complex things like your

56
00:02:49,650 --> 00:02:54,638
Adrenocorticotropic hormone
or luteinizing hormone.

57
00:02:54,638 --> 00:02:56,537
So we have various different hormones

58
00:02:56,537 --> 00:02:59,300
from the endocrine system that

59
00:02:59,300 --> 00:03:02,217
are being transported in the blood.

60
00:03:03,824 --> 00:03:06,661
Well the blood also has
a regulatory function.

61
00:03:06,661 --> 00:03:09,730
It helps regulate temperature.

62
00:03:09,730 --> 00:03:11,813
Well how does it do that?

63
00:03:13,532 --> 00:03:15,549
Well if you're outside on a 95 degree day,

64
00:03:15,549 --> 00:03:18,473
in the middle of summer with 90% humidity.

65
00:03:18,473 --> 00:03:20,784
What are you doing?

66
00:03:20,784 --> 00:03:22,051
Besides complaining about how hot it is

67
00:03:22,051 --> 00:03:24,275
you're probably going to be sweating.

68
00:03:24,275 --> 00:03:28,289
Sweating is going to be the
liquid from in your blood,

69
00:03:28,289 --> 00:03:30,539
is allowing some to seep out of

70
00:03:30,539 --> 00:03:32,445
the skin through capillaries.

71
00:03:32,445 --> 00:03:36,552
Tiny little blood vessels
that can help cool you down.

72
00:03:36,552 --> 00:03:39,713
Helps control the water
volume in your body.

73
00:03:39,713 --> 00:03:41,548
If you get too much water volume,

74
00:03:41,548 --> 00:03:45,493
it starts to reach the
kidneys and excrete it.

75
00:03:45,493 --> 00:03:46,326
pH.

76
00:03:47,301 --> 00:03:51,146
Well it balances your
acid and base levels.

77
00:03:51,146 --> 00:03:55,897
The blood is actually
buffered within your system.

78
00:03:55,897 --> 00:03:58,406
A buffer is anything that will help

79
00:03:58,406 --> 00:04:02,156
to prevent drastic changes in pH.

80
00:04:04,978 --> 00:04:07,047
Blood helps defense.

81
00:04:07,047 --> 00:04:08,174
Helps prevent against infections.

82
00:04:08,174 --> 00:04:10,118
You have white blood cells in there.

83
00:04:10,118 --> 00:04:11,260
They're going to eat and destroy

84
00:04:11,260 --> 00:04:14,695
anything that's foreign in the body.

85
00:04:14,695 --> 00:04:16,805
It'll also help on a physical nature.

86
00:04:16,805 --> 00:04:18,550
If you have a cut or you're bleeding.

87
00:04:18,550 --> 00:04:19,917
It's going to try and make sure

88
00:04:19,917 --> 00:04:23,417
that you clot that, preventing blood loss.


95
00:04:37,814 --> 00:04:40,550
So, components of blood.

96
00:04:40,550 --> 00:04:43,463
Blood is made of mostly plasma.

97
00:04:43,463 --> 00:04:46,598
Now I have this 55% up here.

98
00:04:46,598 --> 00:04:48,785
55% give or take.

99
00:04:48,785 --> 00:04:49,989
A little more a little less.

100
00:04:49,989 --> 00:04:52,222
It depends on the person.

101
00:04:52,222 --> 00:04:55,714
The idea is the majority
though, is plasma.

102
00:04:55,714 --> 00:04:58,714
And the majority of plasma is water.

103
00:05:00,082 --> 00:05:02,081
So most of the liquid portion of

104
00:05:02,081 --> 00:05:05,184
your blood is just pure water.

105
00:05:05,184 --> 00:05:07,317
But you do add in some other things.

106
00:05:07,317 --> 00:05:09,387
Add in some electrolytes.

107
00:05:09,387 --> 00:05:11,402
Electrolytes are salts, sodium,

108
00:05:11,402 --> 00:05:14,902
potassium, chloride, bicarbonate.

109
00:05:16,473 --> 00:05:17,899
You add in some proteins.

110
00:05:17,899 --> 00:05:21,149
Albumins, clotting proteins, globulins.

111
00:05:22,417 --> 00:05:25,594
You add in some hormones, some gases,

112
00:05:25,594 --> 00:05:28,148
oxygen, carbon dioxide.

113
00:05:28,148 --> 00:05:32,360
Some more nutrients and
then eventually the wastes.

114
00:05:32,360 --> 00:05:36,527
The plasma is where all
of this will be contained.

115
00:05:38,519 --> 00:05:42,487
The rest of the blood
is the formed elements.

116
00:05:42,487 --> 00:05:44,413
Now again, don't memorize
the percentage here.

117
00:05:44,413 --> 00:05:47,866
Just the idea that it's less than half.

118
00:05:47,866 --> 00:05:50,748
The formed elements are
made of three components:

119
00:05:50,748 --> 00:05:52,744
Red Blood Cells, known as RBC's

120
00:05:52,744 --> 00:05:55,494
or more technically Erythrocytes.

121
00:05:56,692 --> 00:06:00,002
You have White Blood Cells, WBC's

122
00:06:00,002 --> 00:06:03,264
or more technically known as Leukocytes.

123
00:06:03,264 --> 00:06:04,684
Then you have Platelets with the

124
00:06:04,684 --> 00:06:08,285
more technical term of Thrombocytes.

125
00:06:08,285 --> 00:06:09,693
Now the reason they're called formed

126
00:06:09,693 --> 00:06:12,209
elements is the red blood cells

127
00:06:12,209 --> 00:06:14,903
and white blood cells are cells,

128
00:06:14,903 --> 00:06:18,243
but the platelets are not cells.

129
00:06:18,243 --> 00:06:22,654
The platelets are just
fragments of a cell.

130
00:06:22,654 --> 00:06:24,305
So you can't call all three cells,

131
00:06:24,305 --> 00:06:26,464
that's why they're called formed elements.

132
00:06:26,464 --> 00:06:30,631
Physical structures, they're
found within your blood.

133
00:06:32,376 --> 00:06:35,190
So you can actually do
a test to see how much

134
00:06:35,190 --> 00:06:37,792
formed elements are in your blood.

135
00:06:37,792 --> 00:06:41,949
Now on the far right, you can
see this table top centrifuge.

136
00:06:41,949 --> 00:06:44,591
A centrifuge is just a device that

137
00:06:44,591 --> 00:06:47,755
will spin at very high speeds.

138
00:06:47,755 --> 00:06:49,259
Now when I say very high I mean

139
00:06:49,259 --> 00:06:52,426
10-15 thousand revolutions per minute.

140
00:06:53,549 --> 00:06:54,716
That's moving.

141
00:06:56,083 --> 00:06:58,947
So what's going to happen
here is as it spins,

142
00:06:58,947 --> 00:07:01,437
anything that is heavier,
anything that has more mass,

143
00:07:01,437 --> 00:07:06,394
more weight, is going to get
pushed to the outside edges.

144
00:07:06,394 --> 00:07:08,415
Well in this case, it's pushed to

145
00:07:08,415 --> 00:07:10,582
the bottom of a test tube.

146
00:07:11,594 --> 00:07:12,904
You can kind of think of it as

147
00:07:12,904 --> 00:07:15,221
any of those amusement park rides.

148
00:07:15,221 --> 00:07:16,305
If you've ever been on
one of those amusement

149
00:07:16,305 --> 00:07:18,913
park rides that spins and spins.

150
00:07:18,913 --> 00:07:20,168
Where you're up against the wall

151
00:07:20,168 --> 00:07:22,063
and all of a sudden the floor drops out,

152
00:07:22,063 --> 00:07:26,201
but yet you don't fall down to the floor.

153
00:07:26,201 --> 00:07:28,524
You have this force,
this centrifugal force

154
00:07:28,524 --> 00:07:31,492
pushing you out against the walls.

155
00:07:31,492 --> 00:07:33,379
It's the same idea here.

156
00:07:33,379 --> 00:07:35,205
The red blood cells are going to

157
00:07:35,205 --> 00:07:37,636
have the most mass, the most weight.

158
00:07:37,636 --> 00:07:41,560
They're pushed the furthest
down into the test tube.

159
00:07:41,560 --> 00:07:43,629
Then you get the platelets
and white blood cells

160
00:07:43,629 --> 00:07:45,469
kind of mixed in this little tiny layer,

161
00:07:45,469 --> 00:07:47,427
there's not many of them.

162
00:07:47,427 --> 00:07:48,893
All the plasma's up top.

163
00:07:48,893 --> 00:07:50,361
It's liquid.

164
00:07:50,361 --> 00:07:52,781
So it's the least dense.

165
00:07:52,781 --> 00:07:54,614
It has the least mass.