Biology
how much blood does the average human have?
5-6 litres
the blood has many complex functions to help maintain homeostasis what are they?
transportation- oxygen, co2, food, waste, hormones
protection- blood clotting, defense against disease
regulation- hormones, heat distribution
providing cotting factors- protection from injury
what two things is blood composed of?
blood plasma and cellular components
what is blood plasma look like and what percent does it make up?
thick yellowish fluid and it makes up 55%
what percent does cellular components make up and what three things does it contain?
45% of blood and contains Erythrocytes, leukocytes and platelets (red and white blood cells)
why are erythrocytes unique? hint: the middle
because they do not have a nucleus and is instead filled with hemoglobin which transports oxygen
primary function of red blood cells
to transport oxygen from lungs to the cells in the body
where do dead red blood cells go?
in the liver and spleen to be broken down
white blood cells: what do they contain and shaped like and their function?
irregular shaped, contain a nucleus and protect the body against materials like bacteria and toxins and viruses
where are all cellular components made from?
red bone marrow
what is aggregation?
when platelets rush to site of injury and attach themselves and release chemical reactiond to attract more platelets
what is congulation?
fromation of a clot
what is a stroke?
a clot that blocks a blood vessel in the brain
what is a heart attack?
a clot in the blood vessel in the heart
what in thrombosis?
a clot in your blood vessels
why can clotting happen?
because the anti clotting protien heparin isnt doing its job
what is hemophilia and who does it usually occur in and why is it caused?
it is a rare disorder where the blood cannot clot normally and its usually found in males and it comes from genetics
what is anemia and if you have that what does that mean?
you dont have the normal amount of red blood cells or they dont have enough hemoglobin in them and that means that your blood does not carry enough oxygen to all parts of the body
when can anemia occur? (3)
when the body looses to much blood, body has problems making red blood cells, they die faster than they aremproduced
what is sickle cell anemia and what occurs it?
its is inherited and the red blood cells are hard and have curved edges ( body destroys them but cannot make new ones fast enough therefore anemia occurs)
what is leukemia?
when abnormal cells form in the bone marrow and grow at an uncontrolledd rate and affects the production of white blood cells and thenwhite blood cells build up in the blood causing a halt to the normal blood cells form working right
what is the process of giving and recieving blood?
transfusion
antigens and antibodies are both found in all blood types but differ a little depending on the blood type. what do they do?
antigens- cell markers on the RBC that determine a persons blood type
anitbodies- blood protien that destroys harmful substance like bacteria and viruses and eesponds to and conteracts specific antigens
what is agglutination?
when the types of blood are not matches in transfusion and it can lead to heart attack, embolisms and strokes
4 blood types and their percentages
type A-41%
type B- 10%
type AB- 45%
type O- 4%
what are the Rhesus factors and the percantages of people who have them vs. who dont?
another antigen on the RBC and 85% of people have them and 15% of people dont
what is erythroblastosis fetalis and what can happen to baby?
its a blood diseas where the mother and the baby are not compatible through blood grouping and can cause a still born child. usually the first baby is fine however when its the second one or anytime after there is a very high chance because the antibodies can recognize it far faster
what is used when an emergency transfusion needs to be done and patients blood type is not present?
plasma because it does not have any RBC and antigens
who is the universal recipient and the universal donor?
O is the universal donor and AB is the universal recipient
what does the circulatory system play a vital role in?
maintaining homeostasis
describe pulmonary system and the systemic system
pulmonary system- transports blood from heart to lungs
systemic system- carries blood from heart to all bodily tissues
what do blood vessels do?
channel blood through the body snd make up 2 closed systems that begin and end at the heart
what are arteries?
bloos vessels which carry blood away from the heart and have a pulse
what are the 3 layers in veins and arteries? EEC
Endothelium, elastic and muscle fibers, connective tissues
what are capillaries and what is their function?
connect arterioles and venules and allow for diffusion of materials (super small) and gas exchange
what is the hear surrounded by?
pericardium
what do the valves in the heart do?
regulate blood flow
what are cononary arteries and where do they arise from?
The hearts on source of oxygenated blood and it arises right from the aorta
what are the two main phases of the heart beat?
systole and diastole
when the sound " dub" is heard what happens?
the heart fills with blood ( ventricular relaxation)
when the sound "lub" is heard what happens?
the heart pumps out the blood
what is causing the "lub-dub" sound?
the opening and closing of heart valves
what do purkinje fibers do?
they rapidly control the impules in the heart and makes sure the heart muscles cells contract in an efficient pattern
What is the SA node?
It's initiates the contraction of the atria and ventricles ( also known as a pacemaker)
when the AV node is activated what happens?
Impulses sent down to the bundle of his, going up the septum maming the ventricles contract
What is a heart murmur?
When the valves in the heart are not completely closing and there is a swishing sound because there is blood backflow. Can also be the result of a heart attack
What causes the SA node to fire more rapidly and why is it released?
The medulla oblongata detects carbon dioxide increase and releases noradrenaline ( going to catch a bus)
Why is adrenaline released?
when the nervous system releases hormones called adrenaline because you were experiencing emotions like nervous or angry this is a fight or flight response and can increase heart rate, increase blood flow to the muscles
What are cardiovascular diseases?
Diseases and injuries found in the cardiovascular system
What is a stroke?
Results of blood flow problem to the brain (blood clot)
what is atherosclerosis?
Slow, progressive, thickening and hardening of the arteries
What is Angina?
If the blockage atherosclerosis occurs in a corner artery might be a possible future heart attack or stroke coming
treatments for atherosclerosis
angioplasty- catheter base procedure that unblocks the arteries and a balloon tip is inflated and presses against the plague and widens the vessel
stenting- The balloon is inflated, the stent pops open and the balloon is removed leaving the stent in place
bypass surgery- replaces the clogged arteries and blocked arteries taken from patients on leg or chest
drug therapy- drugs that can be taken to thin the blood like aspirin
what is thrombosis?
The process which a blood clot forms
what is is aneurysm?
bulging out part of the wall of a blood vessel
why do aneurysm form and what can happen?
forms where a wall has the weekend often due to buildup of plaque and if left untreated can burst or tear causing massive internal bleeding and often results in death because it produces little or no symptoms
What are congenital heart disease?
Heart problems that are present at birth
What is congestive heart failure?
condition where the heart does not pump as strongly as it should which can cause back up of fluid (which is congestion) in the lungs and other parts of body
What is congestive heart failure?
Condition where the heart does not pump as strongly as it should causing back up a fluid (congestion) in the lungs and other parts of body
What two factors affect cardiac output?
Heart rate and stroke volume
What is cardiac output?
Amount of blood pumped by the Heart
What is stroke volume?
The amount of blood forced out of the heart with each heartbeat
What is often known as the silent killer?
High blood pressure
What is blood pressure?
Force of blood against the walls of arteries
what 2 things does the arteriolar resistance depend on?
size and elasticity
When measuring blood pressure what two pressures are measured?
Systolic pressure and diastolic pressure
What is hypertension?
Blood pressure that is defined in adults that is greater or equal to 140 systolic pressure or greater or equal to 90 diastolic pressure And can directly increase risk of coronary heart disease
What is a treatment for high blood pressure?
Medication called diuretics