unit 4 lo1 Flashcards
what are the 6 components of the blood and their functions
- erythrocytes (red blood cells transport 02 and C02)
- lymphocytes (white cells that fight infection and destroy virus or ——cancer cells by releasing enzymes)
- neutrophils (white cells that fight of bacteria and viruses by producing anti bodies that engulf and digest bacteria)
- monocytes (white cells destroy and remove dead cells, viruses and fungi and bacteria )
- platelets (help the blood clot)
- plasma (watery substance that transports dissolved nutrients)
how are erythrocytes adapted for their function
biconcave to increase surface area
no nucleas to increase surface area
4 heamaglobin so 4 oxygen can bond and create oxyheamaglobin
thin membrane wall and felxible
what are the 5 functions of the blood
transport, temperature control, fighting infection, exchange of materials with body tissue, and blood clotting
explain the how transport is a function of blood
erythrocytes transport oxygen and carbon dioxide
plasma transports nutrients
some products cannot be got rid of like fat and are carried in the blood in proteins
explain how the blood is involved in temperature control
blood constantly runs through the thermoregulation centre
when the temperature changes signals are sent to the nervous system
vasodilation (when blood vessels widen, cooling you down by increasing the surface area so more heat can be lost through the skin)
vasoconstriction (blood vessels narrow, heating you up as surface area is reduced and less heat is lost)
example of negative feedback
how is blood involved in the exchange of materials with body tissue
plasma diffuses from blood to tissue
becomes tissue fluid
oxygen and glucose diffuse into cells
waste products diffuse along a concentration gradient into tissue fluid
enters capillaries to be removed from body
how is the blood involved in preventing infections
white blood cells form a special protein called antibodies
these lock onto the cell walls making them a target for monocytes which can engulf and digest them
explain how the blood clots
platelets help form scabs
coagulation is a process that turns soluble blood protein into and insoluble form that traps platelets to form blood clots
what is the role of coronary arteries
supply blood to the heart tissue itself
what is the systemic circuit of the heart
pulmonary veins left atrium bicuspid valve left ventricle aortic valve aorta (pumps oxygenated blood around the body)
what is the pulmonary circuit of the heart
superior vena cava right atrium tricuspid valve right ventricle semi lunar valve pulmonary artery (pumps deoxygenated blood to lungs ready for gas exchnage)
what is the difference between systole and diastole
systole- is when blood is pumping out of the heart
diastole- is when blood is pumping into the heart
what is the function of the valves of the heart
keep the blood flowing in the right direction
valves open when there is a difference in pressure on one side compare to the other
tricuspid and bicuspid valves top blood flowing backwards into the atria from the ventricles
closure of these valves means when the ventricles contract blood goes out to the aorta and pulmonary artery rather than backwards
what is the function of the vena cava
brings deoxygenated blood into the heart
what is the function of the pulmonary artery
takes deoxygenated blood away from heart to lungs
what is the function of the aorta
takes oxygenated blood to cells
what is the SA node
bundle of cells which acts as a pacemaker controlling the rate of contraction(heart rate)
located in the upper right atrium of the heart
what is the AV node
responsible for the rythm of contraction by passing the signal to the purkyne fibres located in the ventircle wall
what does an ECG measure
measures electrical impulses
outline what each wave means, P, QRS, T wave
P- atria contracting (small wave)
QRS- ventricles contracting (bigger wave)
T- ventricles relaxing
what is the difference between veins and arteries
veins- thinner less elastic walls because they carry blood away from heart and are under less pressure. Also have one way valves
arteries- thick elastic walls to withstand the pressure of carrying blood around the heart
what are capillaries
one cell thick and allow for the exchange of gases and nutrients between blood and surrounding tissue
what is hydrostatic pressure ?
pressure from the heart beat forcing plasma through the vessels
what is the functions of the lymphatic system
drain fluid from around the tissue
moving cells that need to fight infection around the body
white blood cells like lymphocytes are formed in bone marrow and move to lympnodes for storage and development
explain the formation of tissue fluid
hydrostatic pressure is pressure form the heartbeat pushing plasma through the vessels
the blood goes from the artery to the arterioles and then the capillaries
when the plasma passes through the capillary wall it becomes tissue fluid and when it becomes too much it drains into the lymphatic system
another way is by osmosis into the capillaires. osmosis is the movemnt of water
what is hyperstention
high blood pressure
if the force of the heartbeat is too much it can put pressure on the artery wall
overtime this damages the lumen of the artery, causing it to thicken
this results in a build up of plaque
what are the risk factors of hyperstention
salt as it increases blood volume and therefore= increases blood pressure underlying illness like diabetes overwight ages smoking alcohol
what is systolic and diastolic pressure
systolic - when ventricles contact and blood is forced around the body
diastolic- resistance to blood flow in blood vessels when heart is at rest
what is classed as high and low blood pressure
high - 140/90 mmHg
low-90/60 mmHg
how is hyperstension monitored
blood pressure cuff gp surgery midwife appointment nhs health check 24 hour ambulatory monitoring
what are the treatments for hyperstention
ACE inhibitors- relax blood vessels
Diuretics- reduce excess fluid in blood and therefore reduce blood volume so the pressure of the blood is less
calcium channel blockers-widen blood vessels
what is atheroma
material that accumaltes on the artery wall which can lead to angina
what is angina
sensation of chest pain, pressure, squeezing often due to not enough blood flow and therefore oxygen
indicate increased risk of a heart attack
what is coronary heart disease
when plaque builds up in the coronary arteries, this is called atherosclesrosis
what are the main risk factors for cornonary heart disease
smoking high cholesterol excessive alcohol obesity age
how is CHD monitored
angiogram- an x ray that uses a special dye to see blood in veins blood pressure weight checks BMI high cholesterol through blood tests peak flow test
what are the two treatments for CHD
angioplasty- when a small balloon is inflated to widen narrowed arteries and veins
coronary artery bypass graft- diverts blood around the clogged part of the major artery to improve blood flow and oxygen supply to the heart
what medication can be used to treat CHD
low dose aspirin- reduces the chance of blood clots by stopping platelts sticking together
satins- reduce the cholesterol level in the blood
ace inhibitors- treat high blood pressure
does the right side of the heart carry oxygenated or deoxygenated blood?
right side- oxygenated
left side- deoxygenated
