Blood Flashcards
Blood, blood cells, blood groups
1
Q
What is the circulatory system?
A
- the body’s main internal transport system
- the link between the requirements of cells inside the body and the external environment which provides the requirements
- blood links cells of every body system
- essential for maintaining homeostasis
2
Q
What are the functions of blood?
A
- transport O2 and nutrients to cells
- transport CO2 and waste away from cells
- transport hormones to cells
- maintain pH of bodily fluids
- distribute heat and maintain body temperature
- maintain water content and ion concentration of bodily fluids
- protect against disease
- clotting (for damaged cells)
3
Q
What are the components of blood?
A
- plasma and formed elements
- plasma is the liquid component (makes up 55% of blood volume)
- formed elements are the non liquids (makes up 45%)
- they are the r.b.c (erythrocytes), w.b.c (leucocytes) and platelets (thrombocytes)
- females have 4-5L of blood
- makes have 5-6L of blood
4
Q
What is plasma
A
- liquid component of blood (makes up 55%)
- it’s 91% water
- the rest is dissolved substances
- such as glucose, amino acids, ions, gases, waste, hormones, protein
5
Q
What are white blood cells (leucocytes)? What are the types?
A
- they remove dead and injured cells and invading micro-organisms
- leucocytes are larger but fewer than erythrocytes
- Types:
- granulocytes- granular cytoplasm and lobbed nucleus
- monocytes and lymphocytes- spherical nucleus and agranular cytoplasm
6
Q
What are red blood cells
A
- shaped like biconcave discs
- they have no nucleus to make room for haemoglobin
- haemoglobin combines with oxygen and turns red
- erythrocytes are produced in the bone marrow
- they’re destroyed in the liver and spleen
- life span = abt 120 days
7
Q
What are platelets?
A
- small cell fragment with no nucleus
- formed in bone marrow
- important for blood clotting
- life span: about 7 days
8
Q
What does blood clotting do?
A
- helps minimise blood loss and prevent infection after an injury that causes damage to blood vessels
9
Q
What does blood clotting involve?
A
- vasoconstriction
- platelet plug
- coagulation (for more serious injuries)
10
Q
What is vasoconstriction?
A
- damaged arteries constrict
- reduces blood flow and loss
11
Q
What is a platelet plug?
A
- internal walls of blood vessels become rough
- this causes platelets to stick
- platelets then attract more platlets, creating a platelet plug
- they also release substances that act as vasoconstrictors
- they prolong constriction, limiting blood flow
- this is enough clotting for minor damage
12
Q
What is coagulation?
A
- used when the injury is more severew
- coagulation factors are present in plasm
- they form threads of protein fibrin
- this forms a mesh to trap blood cells, platelets and plasma
- the threads stick to blood vessels, holding the clot in place
- after it forms, clot retraction occurs: this is when fibrin contracts, becoming stronger, pulling the edges together
- the clot dries, forming a scab
13
Q
What is an antigen?
A
- a substance that stimulates the formation of a protein called an antibody
- an antigen is like a marker, indicating what type of cell it is
- if a cell has the wrong antigen, the immune system will make antibodies to combine with the antigen and help wbc’s destroy it
- the surface of rbc’s contain antigens
- antigens are used to classify blood groups
14
Q
What are the types of antigens?
A
- antigen A and antigen B
- rbc’s have antigen A, antigen B, both or none
15
Q
What antigen does blood type A have?
A
antigen A
16
Q
What antigen does blood type B have?
A
antigen B
17
Q
What antigen does blood type AB have?
A
antigen A and antigen B
18
Q
A
19
Q
Antigen A produces…
A
antibody B
20
Q
Antigen B produces…
A
antibody A
21
Q
Antigen A and antigen B produces…
A
no antibodies
22
Q
Having neither antigens produces…
A
antibody A and antibody B
23
Q
What are rhesus blood groups?
A
- named because of the Rhesus monkey blood used in experiments
- has Rh antigen = Rh positive
- doesn’t have Rh antigen = Rh negative
- Rh positive= can’t produce anti Rh antibodies
- Rh negative= produces anti Rh antibodies
