Blood Circulatory System Flashcards
what type of tissue is blood?
connective tissue
amount of blood in an average adult
5-6L
circulatory system consists of (3)
blood
the heart
blood vessels
blood consists of (2)
plasma
blood cells
what is plasma?
pale gold liquid
% of plasma in blood
55%
2 components of plasma
water
dissolved solids
percentage of water in plasma
90%
percentage of dissolved solids in plasma
10%
function of water in plasma
acts as the solvent
6 dissolved solids in plasma
blood proteins soluble food mineral salts dissolved gases dissolved wastes hormones
main functional part of blood proteins
antibodies
where are antibodies produced?
by white blood cells
where do antibodies enter the blood?
from lymphocytes
where are antibodies transported?
in the plasma
where are antibodies involved?
in our immune system
a second important blood protein
clotting proteins
function of clotting proteins
help the blood to form clots when needed
from where do clotting proteins enter the blood?
the liver
soluble food in plasma
glucose and amino acids
from where are soluble foods absorbed?
from the small intestine
to where are the glucose and amino acids brought
to the liver
after the liver where are the soluble foods brought?
to where they are needed in the body
how are mineral salts transported in the blood
as ions
3 ion salts in blood
Na+ Cl- Ca++
example of dissolved gas in blood
carbon dioxide
where is carbon dioxide produced?
in respiration
where does carbon dioxide enter the bloodstream?
from the cells
an example of dissolved waste in blood
urea
where does the urea come from?
liver
where does the urea go to?
the kidneys
where are the hormones secreted from?
the endocrine glands
where are the hormones carried to?
where they affect the body (a target organ)
plasma alo carries
heat
serum
plasma from which the clotting proteins have been removed
why would clotting proteins be removed from plasma
for a transfusion you don’t want it to clot
name for clotting proteins
fibrinogen
3 types of blood cells
red blood cells
white blood cells
platelets
name for red blood cells
erythrocytes
3 places red blood cells are made
bone marrow of ribs, arms and legs, and vertebrae
where are old red blood cells broken down
in the liver and the spleen
rate at which red blood cells are broken down
3 million cells per second
why do red blood cells become damaged?
they’re constantly changing shape to pass through narrow blood vessels
where is the iron from the haemoglobin stored?
in the liver
2 things that happens to used iron
- recycled and used to make new haemoglobin
2. converted into bile pigments
life span of red blood cells
about 4 months
what does haemoglobin do?
joins with oxygen in areas of high oxygen concentration and releases oxygen in areas low oxygen concentration
area of high oxygen concentration
lungs
area of low oxygen concentration
body cells
oxygen binds to haemoglobin to make
oxyhaemoglobin
function of red blood cells
transport oxygen
colour of haemoglobin
purple
colour of oxyhaemoglobin
bright red
anaemia
a lack of haemoglobin or red blood cells
2 symptoms of anaemia
pale skin colour
loss of energy
what does haemoglobin also bind to?
carbon monoxide
what is the problem with haemoglobin binding to carbon monoxide?
it greatly reduces the amount of oxygen that is transported around the body, it kills quickly
where can you find CO (2)
car exhausts
cigarettes
shape of red blood cells
biconcave disk
why are biconcave disks a good shape
larger surface area to exchange oxygen
when do red blood cells lose their nuclei?
within a few days mature
what is not in red blood cells (2)
nuclei
mitochondria
why do red blood cells not have nuclei and mitochondria
to allow maximum space for haemoglobin molecules
membrane of red blood cells
thin flexible membrane
why do red blood cells have a thin flexible membrane?
to move through small blood vessels, capillaries
name for white blood cells
leukocytes
largest blood cells
white blood cells
shape of white blood cells
no definite shape
1 white blood cell=
700 red blood cells
nucleus in white blood cell
large nucleus
function of white blood cells
protection against disease
2 types of leukocytes
lymphocytes
monocytes
leukocytes percentage of white blood cells
23%
2 places leukocytes are made
in bone marrow and lymph nodes
where are lymphocytes stored?
in parts of the lymphatic system
5 places in lymphatic system where lymphocytes are stored
spleen lymph nodes tonsils adenoids thymus glands
how long can lymphocytes survive?
between 3 months and 10 years
main function of lymphocytes
make antibodies
what are antibodies?
proteins made by lymphocytes in response to foreign antigens
what are antigens?
foreign molecules found on the surface of pathogens
structure of lymphocytes
large round nucleus with very little cytoplasm
function of antibodies
help the body to fight infection by micro-organisms eg.bacteria
monocytes percentage of all white blood cells
5% of all white blood cells
where are monocytes made
in the bone marrow
survival of monocytes
6-9 days
what are macrophages
a type of monocyte
phagocytosis
the process by which large particles are engulfed by the cell and become incorporated into a vacuole within the cell
monocytes are
phagocitic
main function of moncytes
to engulf pathogens such as bacteria name for platelets
name for platelets
thrombocytes
what are platelets made from?
fragments of a large cell called a magacyte
where are platelets made?
in the bone marrow
shape of platelets
no definite shape
do thrombocytes have a a nucleus?
no
function of platelets
blood clotting
2 main functions of blood clotting
reduce the loss of blood
prevent entry of micro-organisms
haemophiliacs
unable to produce one or more of the clotting chemicals and as a result cannot form blood clots. they can bleed excessively when cut
thrombosis
a blood clot that forms within a blood vessel and may block it, can lead to heart attack or stroke
5 functions of blood
- transports food, wastes, hormones etc. in plasma
- transports oxygen in red blood cells
- thermoregulation, transports heat
- monocytes and leukocytes fight disease
- blood clotting - platelets
percentage of irish people with rhesus gene
85%
universal donor and why
O -
no antigens present
universal recipient
AB +
all antigens present
what type of system is the circulatory system
closed system
what does it mean that the circulatory system is a closed system
blood flows in vessels inside the body
2 advantages of a closed system
- blood can be pumped faster around the body
2. blood flow to organs can be regulated, increased or decreased when needed
what does it mean to have an open circulatory system
blood is pumped from the heart into the body to fill areas called sinuses
3 animals with an open circulatory system
snails
crabs
insects
outer layer of arteries
collagen
what type of tissue is collagen
connective tissue
middle layer of arteries
muscle and elastic tissue
lining of lumen in artery
endothelium
middle of artery
small lumen
function of collagen layer in artery
prevents over expansion of artery
type of walls in artery
thick walls made of muscle and elastic tissue
how is blood pushed on in the artery
the muscle contracts
elastic fibres recoil
type of lumen in the artery
narrow lumen
the only 2 arteries with valves
aorta
pulmonary artery
only artery with deoxygenated blood
pulmonary artery
pressure in blood in arteries
high pressure
2 reasons why blood in arteries is under high pressure
arteries closer to heartbeat
narrow lumen
arterioles
small arteries
walls in veins
thin walls with less muscle and elastic tissue
do veins have valves
yes
vein lumen
larger than arteries
why are valves in veins
prevent the backflow of blood as it is under low pressure in veins
only vein carrying oxygenated blood
pulmonary vein
why are veins under low pressure
less muscle in the wall
wide lumen
blood flow in veins helped by (2)
- valves prevent backflow
2. contraction of skeletal muscles in the body
venuoles
small veins
blood flow in arteries
in pulses
blood flow in veins
steady rate
function of capillaries
carry blood from arterioles to venuoles through tissue releasing nurtrients and removing wastes
what are capillaries?
tiny tubes that link arteries and veins
what takes place in the capillaries?
exchange of materials between the blood and body cells
circulatory system summary
heart -> arteries -> arterioles -> capillaries -> venuoles -> veins -> heart
structure of capillaries
lumen and single layer of endometrial cells
how thick are capillaries
one cell thick
why are capillaries one cell thick?
allows for rapid and easy movement of molecules in and out
why do capillaries have a narrow lumen
slow blood flow to allow time for exchange of materials
do capillaries have branching?
yes
why do capillaries have branching
to increase the surface area for exchange of materials and allow all tissue cells to be close to a capillary
portal vein
capillaries at both ends
carries blood from one organ to another
example of portal vein
carries blood from small intestine to liver
where is the heart?
in the thoracic cavity
what protects the heart?
the ribcage and the sternum
double circulatory system
the heart is a double pump
what does the septum separate?
oxygenated and deoxygenated blood
blood on left side of heart
oxygenated
blood on right of heart
deoxygenated
2 circuit
pulmonary circuit
systemic circuit
the pulmonary circulation
deoxygenated blood from right side of heart to lungs and oxygenated blood from lungs to left side of heart
the systemic circulation
oxygenated blood from left side of heart to body cells and deoxygenated blood from cells t right side of the body
advantages of double circulation (2)
separates oxygenated and deoxygenated blood
maintains high blood pressure to ensure blood reaches all areas of the body
diastole
relaxation of the cardiac muscle
systole
the contraction of parts of the heart
what does SA node stand for
sino atrial node
other name for SA node
pacemaker
what is the SA node?
a specialised tissue located in the upper right wall of the right atrium
function of the SA node?
sends out regular electrical impulses which cause the atria to contract
what does AV node stand for?
atrio ventricular node
what is the AV node?
a piece of specialised tissue located in the septum at the base of the right atrium
aorta
largest artery in the body
carries oxygenated blood to mot of the major organs in the body
vena cava
carries deoxygenated blood from the body back to the heart
2 vena cava
superior and inferior
superior vena cava
carries blood from upper part of the body
inferior vena cava
carries blood from lower part of the body
pulmonary artery
carries deoxygenated blood from the right side of the heart to the lungs
excretes carbon dioxide and absorbs oxygen
pulmonary vein
carries oxygenated blood from lungs to left hand side of heart
4 chambers of the heart
left and right atria and left and right ventricles
septum
divides the heart into two separate pumps
thickest wall of heart in
left ventricle
how many cusps do valves have? `
3
which valve doesn’t have 3 cusps?
2 in bicuspid valve
bicuspid valve
from left atrium into left ventricle
tricuspid valve
from right atrium to right ventricle
semi-lunar valves
in aorta and pulmonary artery
chordae tendineae
connective tissue holding heart valves in position
papillary muscle
attaches chordae tendineae to the ventricular walls
where is the blood supply to the heart
in the coronary arteries and veins
where does the coronary artery start and end
branches of the aorta and branches into many capillaries in the heart muscle
where do the coronary veins start and end
the capillaries join back up into veins and they return to the right atrium
blockage of the coronary artery
leads to a heart attack
how long does diastole last?
about .4 seconds
atrial systole
- SA node sends electrical impulse
- cardiac muscle in atrial wall contracts
more blood pushed into ventricles
ventricular systole
- stimulus for contraction passed to AV node
- cardiac muscle of ventricle wall contract
- bicuspid and tricuspid valves shut
- semi-lunar valves open
- blood forced into the arteries
- semi-lunar valves shut
atrial systole lasts
0.1 seconds
ventricular systole lasts
0.3 seconds
average length of cardiac cycle
.8 seconds
average adult heart rate
70 bpm
what is pulse
the alternative expansion and contraction of the arteries
indicative of the heart rate
what is blood pressure?
the force exerted by the blood against the walls of the artery
what causes the aorta to expand?
blood forced into the aorta during the contraction of the ventricles
what causes the aorta to contract?
due to the elastic tissue in the wall
2 values of blood pressure
systolic and diastolic
normal blood pressure value
120/80
unit of blood pressure
mm Hg (millimetres of mercury)
top value of blood pressure
value in artery when heart is contracting
bottom value of blood pressure
value in artery when heart is relaxed
LORD
left oxygenated
right deoxygenated
leading cause of death in ireland
cardiovascular disease
What is atherosclerosis?
a disease of the blood vessels, causes hardening of the arteries
what causes atherosclerosis?
too much cholesterol in the diet causing fatty deposits to build up under the lining of the artery
what does an atheroma do?
it narrows the lumen of the artery which causes a rise in blood pressure
what can an atheroma lead to?
the development of a blood clot or embolus
what an a blood clot or embolus lead to?
t can block an artery and cause heart attack or stroke
angina
when an there is an atheroma in the coronary arteries
3 main factors affecting risk of cardiovascular disease?
smoking
diet
exercise
2 things nicotine does to make a greater risk of heart attack
- stimulates adrenaline, faster heart rate and higher blood pressure put heart under pressure, extra stress
- makes heart muscle more excitable, which causes extra heartbeats
extra heartbeats
heart arrhythmia
how does carbon monoxide in cigarettes increase the risk of cardiovascular disease?
destroys the oxygen carrying abilities of the red blood cells by binding to the haemoglobin
what type of diet can increase the risk of narrowing the arteries?
a diet high in animal fat
what does less fat in the diet do for the heart?
makes it easier to lose weight which puts less strain on the heart
what is high salt intake linked to?
higher blood pressure
what is being overweight linked to?
higher blood pressure
what does higher blood pressure lead to?
increased risk pf cardiovascular disease
what does exercise increase? (2)
enlarges the heart strengthens the heart muscle
what does exercise decrease (3)
lowers blood pressure, decreases body fat and cholesterol levels
3 other factors affecting cardiovascular
genetic
age
stress
5 treatments for cardiovascular disease
stop smoking increase activity healthy diet with reduced amnimal fat medication to lower blood pressure and cholesterol surgery
