Blood (Ch.2 Sec.2) Flashcards
1
Q
What are the two main functions of blood?
A
Transport nutrients and oxygen to the cells, carry carbon dioxide and other waste materials away from the cells.
2
Q
What is blood composed of?
A
Plasma (55 percent) and formed elements (45 percent) including red blood cells, white blood cells, and platelets.
3
Q
What is the liquid part of blood called?
A
Plasma
4
Q
What percentage of plasma is water?
A
About 90 percent
5
Q
What role does albumin play in plasma?
A
Regulation of osmotic pressure between plasma and blood cells, and plasma and tissues.
6
Q
What is the primary function of red blood cells?
A
Transport oxygen to cells in all parts of the body.
7
Q
What is hemoglobin?
A
An iron-containing protein that transports oxygen and carbon dioxide.
8
Q
Where are red blood cells formed?
A
In the red marrow of bones.
9
Q
What happens to the cell nucleus and organelles during the formation of a red blood cell?
A
They disintegrate.
10
Q
What are the components of blood that make up the formed elements?
A
Red blood cells, white blood cells, and platelets.
11
Q
True or False: Plasma carries hormones.
A
True
12
Q
Fill in the blank: The liquid medium of blood is called _______.
A
plasma
13
Q
What type of white blood cell is involved in fighting disease?
A
Phagocyte
14
Q
What are the types of blood cells?
A
Red blood cells, white blood cells, platelets.
15
Q
What is the volume of blood in a healthy adult?
A
About 4 to 5 litres.
16
Q
What is the function of antibodies in plasma?
A
Help the body fight disease.
17
Q
What is the shape of a mature red blood cell?
A
Biconcave disk-shaped.
18
Q
What is the main role of platelets?
A
Essential for blood clot formation.
19
Q
What determines the compatibility of blood types for transfusion?
A
Blood type antigens and antibodies.
20
Q
What is the Rh factor?
A
A protein that can be present on the surface of red blood cells.
21
Q
Because red blood cells lack nuclei
A
they cannot divide and they
22
Q
have a limited survival period
A
usually 120 to 130 days.
23
Q
White Blood Cells
A
24
Q
(Have an irregular Shope)
A
25
White blood cells
or leukocytes (LOO-kuh-siets)
26
body against disease. They are formed in the red marrow
but some
27
must travel to lymph nodes
tonsils
28
mature. White blood cells are larger than red blood cells and sig-
29
nificantly less plentiful. Each cubic millimeter of blood normally
30
contains about 4 million red blood cells and 7
000 white blood
31
cells. White blood cells can squeeze their way through openings in
32
the walls of blood vessels and into the intercellular fluid. In that
33
way
white blood cells can reach the site of infection and help
34
destroy invading microorganisms.
35
The white blood cell shown in Figure 2-12 is the type of white
36
blood cell known as a phagocyte (FA-guh-siet). Phagocytes are cells
37
that engulf invading microorganisms. Locate the microorganisms
38
that are being engulfed by the phagocyte in Figure 2 -12. Another
39
type of white blood cell produces antibodies. Antibodies are pro-
40
teins that help destroy substances
such as bacteria and viruses
41
that enter the body and can cause disease. When a person has an
42
infection
the number of white blood cells can double.
43
Word Roots and Origins
44
leukocyte
45
from the Greek leuco
meaning
46
"white," and cyte
meaning "cell"
47
FIGURE 2-12
48
Some white blood cells
like the
49
phagocyte shown in blue
engulf and
50
destroy invading microorganisms.
51
Platelets
52
Platelets are not whole cells. They are fragments of very large cells
53
that were formed in the bone marrow. As you can see in Figure 2-13a.
54
Platelets lack a nucleus and have a life span of 7 to 12 days. A cubic
55
millimeter of blood may contain as many as half a million platelets.
56
Platelets are essential to the formation of a blood clot. A blood clot
57
is a mass of interwoven fibers and blood cells that prevents excess
58
loss of blood from a wound.
59
When a blood vessel tears or rips
platelets congregate at the
60
damaged site
sticking together and forming a small plug. The ves-
61
sel constricts
slowing blood flow to the area. Then
62
factors are released from the platelets and the damaged tissue.
63
These factors begin a series of chemical reactions that occur at the
64
site of the bleeding. The last step in this series brings about the
65
production of a protein called fibrin. Fibrin molecules consist of
66
long
sticky chains. As you can see in Figure 2-14
67
form a net that traps red blood cells
and the mass of fibrin and red
68
blood cells hardens into a clot
or scab.
69
Hemophilia is a disorder caused by the absence of one or more
70
of the proteins required for blood clotting. When a person with
71
hemophilia is injured
bleeding continues for much longer than it
72
would in a person without hemophilia. Large cuts or internal
73
injuries can be life threatening. Today
people with hemophilia are
74
treated with injections of the missing clotting factors.
75
Stimulus
76
Blood vessel
77
damage
78
Platelets release
79
clotting protein
80
(enzyme)
81
Clotting
82
reaction occurs
83
Result
84
Blood clot
85
Fibrin net forms
86
trapping blood cells
87
and platelets
88
Platelets
89
Platelets are not whole cells. They are fragments of very large cells
90
that were formed in the bone marrow. As you can see in Figure 2-13a.
91
Platelets lack a nucleus and have a life span of 7 to 12 days. A cubic
92
millimeter of blood may contain as many as half a million platelets.
93
Platelets are essential to the formation of a blood clot. A blood clot
94
is a mass of interwoven fibers and blood cells that prevents excess
95
loss of blood from a wound.
96
When a blood vessel tears or rips
platelets congregate at the
97
damaged site
sticking together and forming a small plug. The ves-
98
sel constricts
slowing blood flow to the area. Then
99
factors are released from the platelets and the damaged tissue.
100
These factors begin a series of chemical reactions that occur at the
101
site of the bleeding. The last step in this series brings about the
102
production of a protein called fibrin. Fibrin molecules consist of
103
long
sticky chains. As you can see in Figure 2-14
104
form a net that traps red blood cells
and the mass of fibrin and red
105
blood cells hardens into a clot
or scab.
106
Hemophilia is a disorder caused by the absence of one or more
107
of the proteins required for blood clotting. When a person with
108
hemophilia is injured
bleeding continues for much longer than it
109
would in a person without hemophilia. Large cuts or internal
110
injuries can be life threatening. Today
people with hemophilia are
111
treated with injections of the missing clotting factors.
112
Stimulus
113
Blood vessel
114
damage
115
Platelets release
116
clotting protein
117
(enzyme)
118
Clotting
119
reaction occurs
120
Result
121
Blood clot
122
Fibrin net forms
123
trapping blood cells
124
and platelets
125
BLOOD TYPES
126
Blood type is determined by the type of antigen present on the sur-
127
face of the red blood cells. An antigen is a substance that stimulates
128
an immune response. Antigens that are normally present in a per-
129
son's body provoke no response. However
when foreign antigens
130
enter the body
cells respond by producing antibodies. In fact
131
word antigen is an abbreviation for "antibody-generating substance."
132
In the early 1900s
Karl Landsteiner used blood taken from his
133
laboratory workers and made observations similar to those you
134
see in Figure 2-15. He noticed that mixing blood samples from
135
two people sometimes resulted in the cells clumping together
or
136
agglutinating. When samples of two different blood types are mixed
137
This
138
together
reactions occur between the antigens on the red blood
139
intederes
140
withe cells and the antibodies in the plasma
causing the cells to aggluti-
141
blood
142
circus nate. When samples of the same blood type are mixed
no reaction
143
occurs
and the blood cells do not agglutinate.
144
Landsteiner's observations led to the classification of human
145
blood by blood types. Three of the most important human antigens
146
are called A
B
147
below
is based on the A and B antigens.
148
A-B-O System
149
The A-B-O system is a means of classifying blood by the antigens
150
located on the surface of the red blood cells and the antibodies cir-
151
culating in the plasma. As shown in Table 2-1
an individual's red
152
blood cells may carry an A antigen
a B antigen
153
gens
or no antigen at all. These antigen patterns are called blood
154
types A
B
155
Notice in Table 2-1 that an individual with type A blood also has
156
anti-B antibodies against type B blood. If type B blood is given to a
157
recipient with type A blood
the recipient's anti-B antibodies will
158
react with the B antigens on the donated red blood cells and the
159
blood will agglutinate. In addition
the donor's type B blood has anti-
160
A antibodies. Their presence will compound the antigen-antibody
161
reaction. The result will be agglutinated blood that will block the
162
flow of blood through the vessels. For this reason
transfusion recip-
163
ients must receive blood that is compatible with their own.
164
(a)
165
(b)
166
FIGURE 2-15
167
Notice that there is no agglutination of
168
red blood cells in the slide in (a)
where
169
blood samples from two people with
170
the same blood type were mixed
171
Compare this with the slide in (b)
172
where blood samples from two people
173
with different blood types were mixed.
174
TABLE 2-1 Blood Types
Antigens
175
Blood types
176
Antigen on the
177
red blood cells
178
AB
179
0
180
A and B
181
none
182
Antibodies in the
183
plasma
184
anti-B
185
anti-A
186
none
187
anti-A
anti-B
188
Can get blood from
189
O
A
190
0
B
191
A
B
192
0
193
Can give blood to
194
A
AB
195
B
AB
196
AB
197
A
B
198
34
199
CHAPTER 2
200
People who have type AB blood are universal recipients. They
201
can receive A
B
202
or anti-B antibodies. People who have type O blood are universal
203
donors. They can donate blood to people who have A
B
204
O blood because the blood cells of people who have type 0 blood
205
do not have A or B antigens.
206
Rh System
207
An antigen that is sometimes present on the surface of red blood
208
cells is the Rh factor
named after the rhesus monkey in which
209
it was first discovered. Eighty-five percent of the United States' popu-
210
lation is Rh-positive (Rh*)
meaning that Rh antigens are present.
211
People who do not have Rh antigens are called Rh-negative (Rh~):
212
If an Rh- person receives a transfusion of blood that has Rh+
213
antigens
antibodies may react with the antigen and agglutination
214
will occur. The most serious problem with Rh incompatibility
215
occurs during pregnancy. If the mother is Rh and the father is
216
Rh+
the child may inherit the dominant Rh+ allele from the father.
217
During delivery
a small amount of the fetus's Rh+ blood may reach
218
the mother's bloodstream. If this happens
the mother will develop
219
antibodies to the Rh factor. If a second Rh+ child is conceived later
220
the mother's antibodies can cross the placenta and attack the
221
blood of the fetus. This condition is called erythroblastosis fetalis.
222
The fetus may die as a result of this condition
or if the child is born
223
alive
he or she may need an immediate transfusion of Rh+ blood.
224
To prevent this condition
an Rh- mother of an Rh+ child can be
225
given antibodies to destroy any Rh+ cells that have entered her
226
bloodstream from the fetus. The mother is
in effect
227
against the Rh antigen before her immune system has a chance to
228
develop its own antibodies. The antibody treatment prevents Rh
229
sensitization in Rh women only if their bodies have not already
230
produced Rh antibodies. If an Rh™ mother has not yet been sensi-
231
tized
she receives the antibody treatment in the 28th week of preg-
232
nancy and again immediately after delivery.
233
People who have type AB blood are universal recipients. They
234
can receive A
B
235
or anti-B antibodies. People who have type O blood are universal
236
donors. They can donate blood to people who have A
B
237
O blood because the blood cells of people who have type 0 blood
238
do not have A or B antigens.
239
Rh System
240
An antigen that is sometimes present on the surface of red blood
241
cells is the Rh factor
named after the rhesus monkey in which
242
it was first discovered. Eighty-five percent of the United States' popu-
243
lation is Rh-positive (Rh*)
meaning that Rh antigens are present.
244
People who do not have Rh antigens are called Rh-negative (Rh~):
245
If an Rh- person receives a transfusion of blood that has Rh+
246
antigens
antibodies may react with the antigen and agglutination
247
will occur. The most serious problem with Rh incompatibility
248
occurs during pregnancy. If the mother is Rh and the father is
249
Rh+
the child may inherit the dominant Rh+ allele from the father.
250
During delivery
a small amount of the fetus's Rh+ blood may reach
251
the mother's bloodstream. If this happens
the mother will develop
252
antibodies to the Rh factor. If a second Rh+ child is conceived later
253
the mother's antibodies can cross the placenta and attack the
254
blood of the fetus. This condition is called erythroblastosis fetalis.
255
The fetus may die as a result of this condition
or if the child is born
256
alive
he or she may need an immediate transfusion of Rh+ blood.
257
To prevent this condition
an Rh- mother of an Rh+ child can be
258
given antibodies to destroy any Rh+ cells that have entered her
259
bloodstream from the fetus. The mother is
in effect
260
against the Rh antigen before her immune system has a chance to
261
develop its own antibodies. The antibody treatment prevents Rh
262
sensitization in Rh women only if their bodies have not already
263
produced Rh antibodies. If an Rh™ mother has not yet been sensi-
264
tized
she receives the antibody treatment in the 28th week of preg-
265
nancy and again immediately after delivery.
