Blood Flashcards
1
Q
Intro
A
- blood is a liquid connective tissue made up of plasma (55%) and formed elements (45%)
- formed elements are the various kinds of blood cells
- 3 general functions: transportation, regulation, and protection
2
Q
Formed elements of blood
A
- 45% total blood volume
- RBCs, WBCs, and platelets
3
Q
Blood volume
A
- about 8% of total body weight in average-sized adults
- blood volume varies according to age, body type, sex, and method of measurement
- females = 4-5L
- males = 5-6L
4
Q
Hematocrit
A
The volume percent of red blood cells in whole blood (centrifuge)
5
Q
Blood plasma
A
- plasma = whole blood - formed elements
- the liquid part of blood; clear, straw-colored fluid made of 90% water and 10% solutes
- maintains normal circulation
- solutes 6-8% of plasma solutes are proteins, consisting of 3 main compounds
1. Albumins: maintain osmotic balance of blood
2. Globulins: essential component of the immunity mechanism
3. Fibrinogen: key role in blood clotting
6
Q
Erythrocytes
A
Bicóncavo discs to increase surface area
- hemoglobin: red protein pigment is the primary component
- RBCs are the most numerous of the formed elements
7
Q
Functions of RBCs
A
- transport of oxygen and carbon dioxide in the body
- both of these functions depend on hemoglobin (280 million hemoglobin molecules/RBC)
- the total surface area of all RBCs in an adult is enormous
8
Q
Hemoglobin
A
- approx 200-300 million molecules of hemoglobin within each RBC
- each hemoglobin is made of 4 protein chains
- each protein chain is bound to red pigment which contains one iron atom (heme group)
- the structure allows each hemoglobin molecule to attach with four O2 which allows RBC to transport O2 where it it needed
9
Q
Anemia
A
Lack of blood
- used to describe a reduction in the number or volume of functional RBCs in a given unit of whole blood
- an adult who has a hemoglobin content of less than 10g/100ml of blood
10
Q
Erythropoiesis
A
Entire process of RBC formation
- RBC formation begins in the red bone marrow with hematopoietic stem cells that go through several stages of development to become erythrocytes
- the entire maturation process requires approx 4 days
- myeloid or lymphoid stem cells
- RBC are formed and destroyed at a rate of approx 100 million/min in an adult
- RBC production speeds up if blood oxygen levels reaching the tissues decrease
- oxygen deficiency increases RBC numbers by increasing the excretion of a hormone named EPO (erythropoietin)
11
Q
Destruction of RBC
A
- life span avg = 105-120 days
- they often break apart, in capillaries as they age
- macrophage cells ingest and destroy the aged abnormal, or fragmented RBC
- iron is returned to the bone marrow for use in synthesis of new hemoglobin
12
Q
Blood types
A
Refers to the type of cell markers or antigens present on RBC membranes
- presence or absence of these antigens determines a persons blood type
13
Q
ABO pic
A
Pic
14
Q
ABO pic
A
Pic
15
Q
ABO explanation
A
A) antigen A
B) antigen B
AB) both antigen A and antigen B; universal recipient
O) neither antigen A nor antigen B RBS; universal donor