LO1 Flashcards
what are erythrocytes
red blood cells
where are red blood cells made
in the bone marrow
why are red blood cells red
because of haemoglobin
what shape are red blood cells
thin, disk-like shape
what are leucocytes
white blood cells
what are leucocytes part of
the bodies immune system
what are the different types of leucocytes
-lymphocytes
-neutrophils
-monocytes
what is a lymphocyte
2 types of lymphocyte,
b-cells and t-cells.
white blood cells.
b-cells develop in the bone marrow and t-cells develop in the thalamus gland.
wide range of functions
what is a neutrophil
small and fast
one of the first type of cells to travel to the site of the infection
what are monocytes
largest of the white blood cells
what is plasma
largest component of blood
55% of blood volume
clear yellowish- coloured liquid
it carries platelets, red blood cells and proteins
function of erythrocytes
-transport oxygen and carbon dioxide within the body.
-don’t have a nucleus- increases space to carry maximum amount of haemoglobin
-haemoglobin binds with oxygen, so erythrocytes are able to transport more oxygen.
-they have a bi-concave shape, round and flattened with a central indentation to maximize the surface area for exposure to oxygen
-they are small and flexible, allowing them to get into narrow blood vessels
what is the function of leucocytes
cells that have a role in defence and immunity
detect abnormal material and destroy it
what is the function of lymphocytes
b-cells produced antibodies to destroy antigens such as bacteria, viruses and toxins
t-cells destroy the bodies own cells that have been taken over by viruses or are cancerous
what is the function of neutrophils
protect the body against bacterial infection
highly mobile and attract to any area of infection by chemicals produced by damaged cells
what is the function of monocytes
part of the immune system. originally formed in the bone marrow, they are released into the blood and tissues. when certain germs enter the body, they quickly rush to the site for attack
what is the function of platelets
help form blood clots by clumping together to slow or stop bleeding and help wounds heal
what is the function of plasma
liquid in which the blood cells are suspended
provides means of transport for glucose, lipids, amino acids, hormones, dissolved food molecules, carbon dioxide and oxygen. Carries fibrinogen which helps with blood clotting. helps with temperature regulation in the body- blood removes heat from tissues such as muscles and circulates it around the body
what are the four chambers in the heart
right atrium, left atrium
right ventricle and left ventricle
left= thicker
what are the main blood vessels leaving or entering the heart chambers
aorta
pulmonary artery
vena cava
pulmonary vein
what is the aorta
main artery of the body
leaves the heart from the left ventricle
what is the pulmonary artery
carries deoxygenated blood from the heart to the lungs
what is the vena cava
the superior vena cava is one of the largest veins in the body
enters right atrium
what is the pulmonary vein
carries oxygenated blood from the lungs to the left atrium of the heart
what are the four valves in the heart
tricuspid
bicuspid
pulmonary
aortic
what is the tricuspid valve
the first valve that the blood encounters as it enters the heart. Tricuspid allows the blood to flow only from the right atrium to the right ventricle
what is the bicuspid valve
also called the mitral valve
allows blood to flow from the left atrium to the left ventricle
what is the pulmonary valve
opening from the right ventricle and stops blood going back from the pulmonary artery into the heart
what is the aortic valve
found at the exit of the left ventricle where the aorta begins
how many circulatory systems does the heart have
2
what are the 2 circulatory systems
pulmonary
systemic
what is the pulmonary circulatory system
right side of the heart receives deoxygenated blood from the body and pumps it to the lungs
what is the systemic circulatory system
left side of the heart receives oxygenated blood from the lungs and pumps it to the rest of the body
how does the blood flow through the heart
- blood from the lungs which is oxygenated, returns to the heart via the pulmonary vein and enters the left atrium
-blood passes through the bicuspid valve to the left ventricle
-blood is forced out of the aorta and carries the oxygenated blood to the rest of the body
-deoxygenated blood returns from the body to the right atrium via the superior and inferior vena cava
-the blood is then squeezed through the tricuspid valve and into the right ventricle
-blood is forced through the pulmonary artery which carries deoxygenated blood to the lungs
what is a healthy adult heart beat
60 to 80 beats per minute
what are the stages of the cardiac cycle
atrial systole
ventricular systole
ventricular systole
complete cardiac diastole
what is atrial systole
contraction of the right and left atria
what is ventricular systole
contraction of the ventricles
what is complete cardiac diastole
relaxation of the atria and ventricles
what is the location and role of the sinoatrial node
situated in the upper wall of the upper wall of the right atrium
‘pacemaker’ and sets the rhythm of the heart
ensures both atria contract simultaneously
location and role of the atrioventricular node
the AV node is situated at the bottom of the right atrium of the heart
responsible for delaying the electrical impulse it receives from the SA node
allows time for blood to empty out of the atria and into the ventricles
what are purkinje fibres
fine specialised cardiac muscle fibres that rapidly transmit impulses from the AV node to the ventricles
what si the order of the ECG trace
. . .R
/ \
—p-~Q/ \S~~~~T
what does the ECG trace tell us about what is happening in the heart
-waves represent the electrical activity of the heart
-the different sections represent the different activities within the heart
-the P waves at the beginning show the atrial contraction
-the QRS complex shows the ventricular contraction (systole)
- the T wave shows the ventricles relaxing (diastole)
what is the sequence that the blood moves around the body
heart- arteries- capillaries- veins- heart
what are arteries
carry blood away from the hear. their walls consist of several layers of thick elastic muscle and fibres
what are veins
have large internal diameters and thinner walls than arteries. the blood flowing through them is not under pressure and so veins have valves through their length. they carry deoxygenated blood back to the lungs
what is a capillary
the smallest blood vessel and have walls made of a single layer of cells. the thin walls of the capillaries allow the exchange of water and waste between the blood and the surrounding tissue
features of an artery
-blood carried away from heart
-oxygenated blood
-blood flows quickly as under pressure
-blood flows in pulses
-walls are thick elastic and musular
-dont have valves except at the base of the large arteries leaving the heart
-internal diameter is small
-artery cross section is round
features of a vein
-blood carried towards the heart
-deoxygenated blood
-blood is under low pressure
-blood flows through smoothly with a squeezing action
-thin walls, little muscle
-valves to prevent backflow
-oval cross section
what does the lymph pass through before getting to the blood
vessels of increasing size
what does the lymphatic system consist of
lymph
lymph vessels
lymph nodes
lymph organs
bone marrow
what is the role of the lymphatic system
-drainage and filtration system
-removes excess fluid from bodily tissues
-absorbs fatty acids and transports fat to the bloodstream to be absorbed into the small intestine
-produces white blood cells which turn into antibodies
what is the role of hydrostatic pressure
hydrostatic pressure is the pressure from heart contractions that forces water and dissolved substances in blood plasma out through the capillary walls into surrounding tissues forming tissue fluid
what is blood plasma
clear straw coloured liquid component of the blood
contain plasma protein which have roles in blood clotting and supporting the immune system
osmotic regulation
what is tissue fluid
fluid between the body cells
interstitial fluid
carries nutrients and oxygen to tissue cells
formed from filtering of blood from capillaries due to hydrostatic pressure
what is lymph
filtered watery fluid drained by the lymphatic system
formed from plasma
contains white blood cells
involved in the removal of wastes and infectious organisms from tissues
explain blood proteins
most abundant is albumins which are the main contributors to the thickness of plasma and to osmotic pressure. the pressure retains fluid in the blood vessels and is the opposite force to hydrostatic pressure. if plasma protein levels fall, the osmotic pressure also falls and fluid leaking from the bloodstream can accumulate in the tissues causing oedema.
second most abundant is globulins- include immunoglobulins and antibodies. These are protective proteins and are essential for the bodies immune response and are made by the lymphocytes.
fibrinogen is for blood clotting and coagulation
symptoms and effects of hypertension
140/90 or higher
rarely has noticeable symptoms
biological explanation of hypertension
blood pressure is recorded with two numbers- the systolic pressure (higher number) is the force at which your heart pumps blood around the body
the diastolic pressure (lower number) is resistance to blood flow in the blood vessels
high blood pressure damages the blood vessels
what is the cause of hypertension
factors that increase are:
age
family history
high salt intake
lack of exercise
being overweight and obese
smoking and drinking alcohol
conditions that can cause it :
kidney disease
diabetes
hormones problems
monitoring, treatment and care needs for hypertension
blood pressure will need to be monitored and readings taken regularly
impact on lifestyle
changing diet- low salt
regular exercise
less alcohol
stop smoking
get enough sleep
reduce stress
medication:
medication usually to lower blood pressure
ACE inhibitors
beta blockers
impacts:
increase risk of CHD, strokes and kidney disease
symptoms of coronary heart disease (CHD)
-angina- breathlessness, nausea, dizziness and chest pain. feeling of tightness in the chest may spread to arms, neck and jaw
-heart attack- myocardial infraction- light headedness, feeling weak, sweating, shortness of breath and chest pain can radiate to chest, jaw, neck and back
biological explanation of CHD
walls of the arteries becomes blocked with fatty deposits, a process called atherosclerosis
when arteries become completely blocked it can cause a heart attack. this can permanently damage the heart muscle and if not treated straight away can be fatal.
what is the cause of CHD
-build up of fatty deposits on the walls of the arteries around the heart. risk of this developing is significantly increased by lifestyle factors such as smoking, lack of exercise and obesity or if a person has high cholesterol or diabetes
age, genes and gender can also influence the likelihood of developing heart disease
monitoring treatment and care needs of CHD
blood test can test the levels of certain fats, cholesterol sugar and proteins in the blood.
an electrocardiogram (ECG) measures the electrical activity of the heart and can show any damage to the heart muscle or signs of CHD
lifestyle changes- reduce fat in diet, more exercising, less smoking
medication
-nitrates relax the coronary arteries and allow more blood to reach the heart used to treat angina
-cholesterol lowing medications eg statins
-antiplatelet medications eg. aspirin make the blood less likely to form clots
-ACE inhibitors lower blood pressure and are used if someone has a heart attack
surgical
-angioplasty passes tiny deflated balloons into a narrow artery and then inflated this pushes the artery open. or a stent or mesh tube
-coronary artery bypass graft surgery to bypass the narrow artery to improve blood flow in the heart
cant be fully treated but adjustments can be made
what does a sphygmometer do
takes your blood pressure
whats the systolic and diastolic values for low blood pressure
s = less than 90 mm/Hg
OR
d = less than 60 mm/Hg
whats the systolic and diastolic values for normal blood pressure
s = 90-120 mm/Hg
AND
d = 60-80 mm/Hg
whats the systolic and diastolic values for pre-hypertension
s = 120-139 mm/Hg
OR
d = 80-89 mm/Hg
whats the systolic and diastolic values for hypertension stage 1
s = 140-159 mm/Hg
OR
d = 90-99 mm/Hg
whats the systolic and diastolic values for hypertension stage 2
s = 160 or higher mm/Hg
OR
d = 100 or higher mm/Hg
whats the systolic and diastolic values for a high blood pressure crisis
s = 180 or higher mm/Hg
OR
d = 110 or higher mm/Hg
