chapter 4 blood Flashcards
what does blood contain
plasma
white blood cells
red blood cells
platelets
what are the blood cells suspended in plasma
red blood cells
white blood cells
platelets
what is the function and structure of red blood cells
they are biconcave and have no nucleus
- increases room for haemoglobin and has a large surface area for efficient diffusion of oxygen into the cell
oxy - haemoglobin
what is the function and structure of white blood cells
protect the body against disease in immune system
lymphocytes - produce antibodies and antigens
phagocytes - engulf pathogens
larger and fewer then red blood cells
what is the function and structure of platelets
cell fragments that are needed for blood clotting
this prevents blood loss and entry of pathogens
what are the effects of anaemia
caused by lack of haemoglobin due to iron deficiency or internal bleeding and excessive blood loss in menstruation
less oxygen carried to cells therefore there is less aerobic respiration and less energy so they become tired more quickly
describe the process of blood clotting
a series of enzyme controlled reactions resulting in the changing of fibrinogen to fibrin which forms a network of fibres trapping blood cells and forming a clot
what are the four main groups of blood
a
b
ab
o
what is blood group o
the universal donor
why is blood typing needed
if the wrong blood type is given then the blood cells will stick together and clump which can be fatal
thi sis because blood groups are determined by antigens on the cell membranes of red blood cells, the immune system produces antibodies which attack the foreign antigens causing it to clump
blood group ab
antigens - A and B
antibodies - none
can donate blood to - A and B
can receive blood from AB, A, B, O
Blood group A
antigens - A
Antibodies - B
can donate blood to - A and AB
can receive blood from - B and O
Blood group B
antigens - B
antibodies - A
can donate blood to - B and AB
can receive blood from - B and O
Blood group O
antigens - none
antibodies - A and B
can donate blood to - AB, A, B, O
can receive blood from - O
how can plasma be used to treat patient due to burns
they dehydrate quickly due to their skin being damaged, the water evapourates from their cells and the plasma transfusion will replace the water and maintain the fluid balance in the body and provide other essential blood components
what do scientists in the national blood service do
determine blood type
ensure blood is free from transmissible disease
separate parts of the blood to make blood products for use in specific treatments
what do physiotherapists do
enable people to recover from heart attacks and strokes
what do the cells require
oxygen and nutrients
what needs to be removed from the cells
waste products like carbon dioxide and urea
what is the link between the pulse and the heart beat
the pulse is the pressure of the blood going into the arteries, the elastic walls stretch and spring back this action is the pulse
what is the structure of the arteries
small lumen
thick layer of muscle and elastic fibres
designed to deal with the high pressure of blood coming out of the heart
what is the structure of the veins
large lumen
thin layer of muscle and elastic fibres
blood is forced back to heart as body muscles press against veins
have valves to prevent the back flow of blood
what is the structure of the capillaries
small lumen one cell thick allow soluble molecules to diffuse across wall and enter cells or allows soluble waste from cells back into blood provides large exchange surface the capillaries are the exchange surface
why do particular blood vessels contain oxygenated or deoxygenated blood
near the lungs or body - double circulation system
describe the structure of the heart
double pump - muscular walls
four chambers - 2 atria and 2 ventricles
atria pump blood to the ventricles
ventricles force blood out of the heart
the right ventricle pumps deoxygentated blood to the lungs
the left ventricle pumps oxygenated blood to the rest of the body
valves prevent backflow
why does the blood change in composition and pressure as it passes through the major organs of the body
its at its highest pressure when its forced out of the ventricles, large arteries maintain pressure as they pulse
the blood branches out into small vessels called arterioles and the pressure decreases as it reached the capillaries
the blood flows more slowly in capillaries and allows time for exchange of food and oxygen
what can cause a heart attack and stroke
blood clots in the brain and heart, they wont receive ocygen and will die which can cause brain damage
what is cholesterol responsible for
artheroma - narrowing of blood vessels which increases the risk of heart attacks and strokes which could result in angina
what is the natural heart rate controlled by
the pacemakes located in the right atrium
what is a artificial pace maker
they are electrical devices to stimulate the heart to beat faster or more regularly
who did the first transplant and how did it work
christain benard in 1967
survived for 18 days before dying of a lung infection
attach to a heart lung machine, this has a pump and a oxygenation system in order to circulate blood to all body cells in the operation - the blood must be kept warm and free from contamination
how does and organ care system work
donor heart is placed in a sterile chamber which keeps the organ at body temperature
the blood from the heart donor is oxygenated and combined with nutrients and pumped into the heart through an aorta which keeps it beating
the blood flows through the heart and leaves via the pulmonary artery
who is a successful heart surgeon
sir Magdi Yacoub - 2000 heart transplants
what happens when you increase exercise
increase oxygen and glucose supply - heart beats faster and you breath deeper
increased carbon dioxide and heat removed
increased production of lactic acid
