Blood Flashcards
What is blood composed of?
Plasma (55%)
Red blood cells (corpuscles,erythrocytes)
White blood cells
Platelets
Plasma Protein
Functions of blood
- TRANSPORT (O2, CO2, products of waste)
- TEMP REGULATION (carries heat and brings water to sweat glands)
- DEFENCE (monocytes, lymphocytes, platelets)
Plasma
liquid, pale yellow
90% water
Transport medium for dissolved and suspended substances
Distributes heat
Dissolved substances
gases (o2, co2)
nutrients
ions
urea
salts
Suspended solids (don’t dissolve)
blood cells
plasma proteins
platelets
hormones
Plasma proteins
antibodies which are produced by white blood cells in order to combine with and neutralise foreign substances
clotting proteins, which are acted upon to form blood clots
Serum definition
is pasma from which the clotting proteins have been removed
Role of plasma
Transport
Distributes heat
Red blood cells: the other name
corpuscles
erythrocytes
Red blood cells
- Tiny biconcave discs
- no nucleus or mitochondria (energy)
- transports O2 (haemoglobin)
- produced in red bone marrow
How long do red blood cells survive for
120 days
destroyed and recycled in liver and spleen
Role of red blood cells
Transports oxygen
Haemoglobin + O2 =
oxyhemoglobin
White blood cells
colourless
larger, no definite shape
less white than red
- have a nucleus
- made in red bone marrow and mature in the lymphatic system
Two types of white blood cells
Monocytes
Lymphocytes
Monocyte
large
engulf damaged/dead cells and pathogens by phagocytosis
also called macrophages/phagocytes
Lymphocyte
produce specific defence proteins called antibodies to fight infection
Platelets
thrombocytes
made in red bone marrow
are cell fragments
Role of platelets
clotting seals ruptured blood/lymph vessels
- maintains blood volume and pressure and prevents entry of pathogens
forms scab
Blood groups
A
B
AB
O (universal doner)
Why is blood type important
important for blood transfusions because the body will make antibodies to destroy cells with foreign antigens on them, therefore a person cannot receive blood with foreign antigens
The Rhesus Factor
is the presence or absence of a chemical called factor D (rhesus factor)
if factor D is present on the surface of the red corpuscles the person is said to be rhesus positive
RH+
RH-
Haemoglobin..
gains oxygen in the lungs forming oxyhaemoglobin
