unit 4 lo1

Question 1

what are the 6 components of the blood and their functions

Answer 1

• 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)

Question 2

how are erythrocytes adapted for their function

Answer 2

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

Question 3

what are the 5 functions of the blood

Answer 3

transport, temperature control, fighting infection, exchange of materials with body tissue, and blood clotting

Question 4

explain the how transport is a function of blood

Answer 4

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

Question 5

explain how the blood is involved in temperature control

Answer 5

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

Question 6

how is blood involved in the exchange of materials with body tissue

Answer 6

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

Question 7

how is the blood involved in preventing infections

Answer 7

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

Question 8

explain how the blood clots

Answer 8

platelets help form scabs
coagulation is a process that turns soluble blood protein into and insoluble form that traps platelets to form blood clots

Question 9

what is the role of coronary arteries

Answer 9

supply blood to the heart tissue itself

Question 10

what is the systemic circuit of the heart

Answer 10

pulmonary veins
left atrium
bicuspid valve
left ventricle
aortic valve
aorta
(pumps oxygenated blood around the body)

Question 11

what is the pulmonary circuit of the heart

Answer 11

superior vena cava
right atrium
tricuspid valve
right ventricle
semi lunar valve
pulmonary artery 
(pumps deoxygenated blood to lungs ready for gas exchnage)

Question 12

what is the difference between systole and diastole

Answer 12

systole- is when blood is pumping out of the heart

diastole- is when blood is pumping into the heart

Question 13

what is the function of the valves of the heart

Answer 13

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

Question 14

what is the function of the vena cava

Answer 14

brings deoxygenated blood into the heart

Question 15

what is the function of the pulmonary artery

Answer 15

takes deoxygenated blood away from heart to lungs

Question 16

what is the function of the aorta

Answer 16

takes oxygenated blood to cells

Question 17

what is the SA node

Answer 17

bundle of cells which acts as a pacemaker controlling the rate of contraction(heart rate)
located in the upper right atrium of the heart

Question 18

what is the AV node

Answer 18

responsible for the rythm of contraction by passing the signal to the purkyne fibres located in the ventircle wall

Question 19

what does an ECG measure

Answer 19

measures electrical impulses

Question 20

outline what each wave means, P, QRS, T wave

Answer 20

P- atria contracting (small wave)
QRS- ventricles contracting (bigger wave)
T- ventricles relaxing

Question 21

what is the difference between veins and arteries

Answer 21

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

Question 22

what are capillaries

Answer 22

one cell thick and allow for the exchange of gases and nutrients between blood and surrounding tissue

Question 23

what is hydrostatic pressure ?

Answer 23

pressure from the heart beat forcing plasma through the vessels

Question 24

what is the functions of the lymphatic system

Answer 24

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

Question 25

explain the formation of tissue fluid

Answer 25

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

Question 26

what is hyperstention

Answer 26

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

Question 27

what are the risk factors of hyperstention

Answer 27

``` salt as it increases blood volume and therefore= increases blood pressure underlying illness like diabetes overwight ages smoking alcohol ```

Question 28

what is systolic and diastolic pressure

Answer 28

systolic - when ventricles contact and blood is forced around the body diastolic- resistance to blood flow in blood vessels when heart is at rest

Question 29

what is classed as high and low blood pressure

Answer 29

high - 140/90 mmHg | low-90/60 mmHg

Question 30

how is hyperstension monitored

Answer 30

``` blood pressure cuff gp surgery midwife appointment nhs health check 24 hour ambulatory monitoring ```

Question 31

what are the treatments for hyperstention

Answer 31

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

Question 32

what is atheroma

Answer 32

material that accumaltes on the artery wall which can lead to angina

Question 33

what is angina

Answer 33

sensation of chest pain, pressure, squeezing often due to not enough blood flow and therefore oxygen indicate increased risk of a heart attack

Question 34

what is coronary heart disease

Answer 34

when plaque builds up in the coronary arteries, this is called atherosclesrosis

Question 35

what are the main risk factors for cornonary heart disease

Answer 35

``` smoking high cholesterol excessive alcohol obesity age ```

Question 36

how is CHD monitored

Answer 36

``` 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 ```

Question 37

what are the two treatments for CHD

Answer 37

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

Question 38

what medication can be used to treat CHD

Answer 38

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

Question 39

does the right side of the heart carry oxygenated or deoxygenated blood?

Answer 39

right side- oxygenated | left side- deoxygenated