wesleys - circulatory system

What are the three types of blood vessels?

arteries, veins, capillaries

arteries

carry blood away from heart

veins

carry blood to the heart

capillairies

small vessels that connect veins and arteries together

thin, permeable walls that allow for exchange of oxygen, water, co2 between blood and body cells

Inelastic protein (collagen) - function

prevents the walls from over expansions

Involuntary muscles and elastic fibres

alter the size of the vessel

why do involunary muscles/elastic fibres do their function

During exercise the muscles can cause the arteries to expand and allow more blood to flow

When body temperature rises, blood vessels dilate, allowing more blood to flow allowing more heat to be lost, allowing us to cool

differences between arteries and veins

arteries carry blood away, high pressure blood, thick walls small lumen and no valves

veins carry blodo to the heart, low pressure blood, thin walls large lumen valves

Blood pressure

force the blood exerts against the wall of an artery.

is blood pressure higher in the veins or arteries ? why ?

higher in arteries as heart contracts to force blood into the artery

how does blood flow through the veins

physical activity squeezes veins, pushing blood around as veins are low pressure, valves prevent backflow of blood

function of capillaries

Allow for the exchange of gases and nutrients between blood and cells

how are capillaries adapted for the exchange of substances

thin walls, very numerous

types of circulatory systems

open and closed

open circulatory system

blood leaves vessels and flows around body cellls, eg insects

closed circulatory system

blood remains in a continuous system of blood vessels

features of heart

between two lungs, above diaphragm, in the thoracic cavity, made up of cardiac muscle, surrounded by double membrane

what reduces friction when the heart moves

pericardial fluid

function of the septum

divides heart into two sides, keeps oxygenated and deoxygenated blood seperate

What vein behaves differently in that it carries very little carbon dioxide and higher levels of oxygen?

pulmonary vein as it is returning oxygenated blood to the heart from the lungs

What artery behaves differently in that it carries very little oxygen and higher levels of carbon dioxide?

pulmonary artery as it is carrying deoxygenated blood to the lungs from the heart

Atria

two upper chambers of heart, thin walls as they only have to pump blood to the ventricles

ventricles

right ventricle pumps blood to the lungs, thin wall as short difference, left ventricle pumps blood to head and lower body, thicker wall as it pumps blood everywehre

tricuspid valve

three flaps, valve on the right side of the heart between right atrium and ventricle

bicuspid valve

two flaps, left side between left atrium and ventricle

semi lunar valves

prevent blood re-entering heart

what is the double sound of the heartbeat caused by

the valves of the heart closing

how does deoxygenated blood travel through the heart

in through vena cava, goes to right atrium, then right atrium contracts and blood goes to right ventricle, which contracts and tricuspid valve closes, blood enters lungs through pulmonary artery to receive oxygen

how does oxygenated blood travel through the heart

blood enters heart through pulmonary vein from lungs, left atrium contracts and blood goes to left ventricle, left ventricle contracts and bicuspid valve closes, allowing blood to be pumped out through aorta to the rest of the body, semi lunar valves close to prevent backflow

pulmonary circuit

heart, lungs, heart

(short, blood gains oxygen and removes co2 in lungs through diffusion)

systematic circuit

heart, body, heart

(long, thick muscle)

Benefits of two circuit system

allows oxygenated blood and deoxygenated blood to be kept apart

Name a vein that carries blood lowest in metabolic waste

Renal vein

Name a vein that carries blood rich in oxygen and has low levels of carbon dioxide

Pulmonary vein

Name an artery that carries blood rich in carbon dioxide and has low levels of oxygen:

pulmonary artery

how is heartbeat controlled

pace maker releases elctrical impulses causing muscle chambers to contract

where is the sa node located

wall of right atrium

where is av node located

septum between right atrium and ventricle

steps of a heart beat

pacemaker releases elctrical impulses, causing atria to contract, this also stimulates the av node

av node sends impulse down muscle of septum, causing ventricles to contract

function of sa node

pacemaker releases elctrical impulses, causing atria to contract, this also stimulates the av node

function of av node

pacemaker releases elctrical impulses, causing atria to contract, this also stimulates the av node

where is the sa node located

wall of right atrum

where is the av node located

septum between right atrium and right ventricle

factors increasing heartbeat

excercise, excitement, shock

factors slowing down heartbeat

sleeping, alcohol

two stages of a heartbeat

diastole, systole

what is the diastole

when the heart chambers relaxs

systole

when the heart chambers contract

What happens when the atria contract?

blood flows intro ventrices, bi and tricuspid valves open and the semi lunar valves stay closed

what happens when the ventricles contract

semi lunar valve opens, and blood gets pushed out of the heart through the aorta and pulmonary artery, tricuspid and bicuspid valves close

Name a vein that transports blood out of the muscle of the heart?

Coronary vein

what do the coronary arteries do

suplly oxygenated blood to the cardiac muscle

what does the coronary vein do

removes deoxygenated blood from the heart

whats a portal system

blood pathway beginning and ending in the capillaries thats not connected directly to the heart, eg the hepatic portal vein

what is the pulse

rhythmic bulging of the artery walls with each heartbeat

why is the neck and wrist good places to measure ur pulse

artery is closest to the surface

What are the health benefits of having a lower pulse rate per minute?

persons heart has the beat less to pump the same amount of blood around

whats blood pressure

force the blood exerts against the wall of an artery

when is blood pressure highest

when left ventricle is contracting

what causes high blood pressure

blockages in arterioles and small arteries, meaning heat has to pump harder

factors effecting blood pressure

age, physical activity, medications

what is plasma

yellow liquid part of blood

types of plasma proteins

antibodies, clotting proteins

function of plasma

transport materials like glucose, amino acids

carries heat around body

where does urea enter plasma

liver

where does co2 enter plasma

from cells as product of respiration

where in body do hormones enter the plasma of the blood

from endocrine glands

red blood cells

produced in bone marrow, contain hemoglobin, 4 month life span, dead red blood cells broken down to produce bile, biconcave in shape

red blood cell shape

biconcave

two types of white blood cells

phagocytes, lymphocytes

phagocytes

engulf and digest bacteria

lymphocytes

produce antibodies to destroy foreign bodies such as bacteria and viruses

features of white blood cells

made in bone marrow, larger than red blood cells, no definite shape, have nucleus

function of white blood cells

fight infections

how do red blood cells differ from white blood cells

red blood cells have no mitochondria or nucleus, white blood cells do

red blood cells are biconcave, white blood cells arent

red blood cells contain haemogloblin and are small, white blood cells are big and have no haemogloblin

platelets

made in bone marrow from cell fragments, clot the blood

functions of blood clots

reduce blood cells, prevent entry of microorganisms

conditions related to clotting

hemophiliacs, thrombosis

4 main blood groups

a, b, ab, o

why is it important to know a persons blood type

in blood transfusions, blood must match person receiving it or else blood may experience clumping

why is it important that blood of a mother and embryo dont mix

different blood types and blood pressures