mass movement animals (JPB) Flashcards
what is the relationship between surface area : volume
as size increases surface area : volume ratio decreases this means that a mass transport system is required
what are common features of a mass transport system
a suitable medium in which to carry materials
a form of mass transport
a closed system of tubular vessels
a mechanism for moving the medium this requires a pressure difference
a pump to transport the medium
how is movement achieved in a transport system / animals
by muscle contraction of the body or the heart
how is movement achieved in a transport system / plants
natural passive processes such as evaporation of water
why are valves important
they maintain the mass flow of blood in one direction
what is a double circulatory system
mammals have them blood stays in the blood vessels and passes through each circuit twice
why is a double circulatory system needed
it is needed as when blood travels through the lungs its pressure is reduced and so blood flow is slow, blood is returned to the left side of the heart to boost the pressure
what is the role of arteries
arteries transport oxygenated blood away from the heart towards tissues at the highest pressure
exception pulmonary artery
what is the role of the veins
veins transport deoxygenated blood towards the heart muscle at the lowest pressure towards the right hand side of heart to lungs to be reoxygenated
exception pulmonary vein
what is the role of the capillaries
where rapid exchange of metabolic materials take place rapidly
they is because :
there are million, provides LSA
one cell thick so SPD
lots of them creating GBS and a steep diffusion gradient
what does renal mean
kidneys
what does pulmonary mean
lungs
features of the aorta
deals with the greatest pressure and is connected to the left ventrical
features of the vena cava
connected to the right atrium and receives low pressure deoxygenated blood from the body
superior and inferior
what is the structure of the heart
a muscular organ that lies in the thoracic cavity
made up of 4 chambers
features of the atrium
both left and right atrium have thin walls that stretch and recoil as they collect blood
features of the ventricles
much thicker muscular wall as they contract strongly to pump blood to the lungs or the body
why is the left ventricle wall so thick
Eris was here
has the thickest muscle wall as
it has the strongest contraction so that a high blood pressure is created to send blood around the entire body
how is the right ventricle adapted
has thin muscle wall as blood only has to travel to the lungs
what does systemic mean
the whole body
features of the lest side of the heart
oxygenated
high blood pressure
to the body
feature of the right side of the heart (you literally cant spell)
deoxygenated
lowest blood pressure
to the lungs to re oxygenate
why are transport systems needed
they are used to move substances over long distances
diffusion also used
what are the valves between the atrium and ventricle called
AV / atrioventricular valves
BICUSPID/left
TRICUSPID/right
why are the AV valves needed
the valves prevent blood into the atria when the ventricles contract/systole
what does the pulmonary artery do
connected to the RV
carries deoxygenated blood to the lungs
it is re oxygenated CO2 removed
what does the pulmonary vein do
connected to the left atrium
brings oxygenated blood back from the lungs
what are the coronary arteries
supply the heart with blood these branch off the aorta shortly after it leaves the heart needed as heart does not meet the oxygen required
blockage of this can lead to myocardial infarcation / heart attack
factors that make it more likely to have a circulatory pump
low SA:V ratio
high metabolism, cells need more oxygen and glucose
advantages of a double circulatory system
increases blood pressure and so increases amount of blood moving to tissue and throughout the body
it re pressurises blood
re oxygenates blood
what are the semilunar valves
aortic / left
pulmonary / right
what is the function of the coronary arteries
carry oxygenated blood to the heart muscle which allows the muscle cells to respire and contracts
what is a risk factor
risk factors is any factor that increase the risk of a disease
examples of risk factors
too much saturated fats
genetics
not enough exercise (sedimentary lifestyle )
too much cholesterol
drugs
too much alcohol
what are the semi lunar valves
aortic valve between the left ventricle and aorta which prevents backflow of blood in aorta
pulmonary valve between the right ventricle and pulmonary artery prevent backflow RA
how is the highest blood pressure produced in the left ventricle
there is the most muscle in the wall which means that their is a stronger contraction so higher pressure
what does systole mean
contraction
what does diastole mean
relaxation
what is one cardiac cycle
one cardiac cycle is 1 heart beat which is roughly 0.7 seconds
what is the cardiac diastole
1st step
cardiac diastole
blood returns from atria through the vena cava and pulmonary artery
AV valves are closed the atrium fill with blood the volume and pressure fill up
gravity aids the movement
what force aids the movement of blood in the heart
gravity
what creates valves to open
AV valves open when the pressure in the atrium are higher than in the ventricle
what is the atrial systole
2nd step
atrial systole the atrium contract as ventricles are relaxed so fill with blood
AS forces blood to ventricles
contraction is weak as blood doesn’t need to travel far and is aided by gravity
what is ventricular systole
short delay between AS and VS
this allows the ventricle to completely fill
allows atria to empty
AV valves close as pressure in atria less than ventricles
semi lunar valves open as pressure in the ventricles is more than the arteries
what is the equasion for cardiac output
CO = HR x SV
what is cardiac output
the volume of the blood pumped out by one ventricle of the heart in 1 minute
what is the average heart rate
60 -100 bpm
what is the stroke volume
the volume of blood pumped out of the LV
what is the normal SV
roughly 70 ml
how do you remember the order of the heart beat
San
Nct
Avn 1
Avn 2
Contraction
purKinje
what is the SAN
the sinoatrial node (pacemaker)
sends impulse across both atrium causing atrial systole
what is the NCT
the non conducting tissue prevents the immediate contracting of ventricles
what is the AVN 1
delays next impulse while the atrium empty and the ventricles fill
what is the AVN 2
impulse sent down the bundle of hiss and up the purkinje fibre
why is the contraction so important in the cell cycle
contraction is apex up which forces all of the blood up and out at a high pressure
what does the ECG record
an ECG records the electrical activity of your heart
what order do the waves occur
P Q R S T
what does the P wave record
atrial systole
what does the QRS wave record
ventricular systole
what does the T wave record
diastole
describe how the heartbeat is initiated and coordinated
the SAN controls the speed and rhythm of the heart by sending an electrical impulse across both atrium
NCT prevents immediate contraction of the ventricles
AVN delays the next impulse so the atrium can empty and ventricles to fill. the AVN then sends an impulse down the bundle of hiss and up the purkinje fibres
this causes contraction of the heart apex up of the heart forcing blood up and out
what is the function of the arteries
usually oxygenated blood at high pressure traveling away from the heart
what is the function of the veins
usually oxygenated blood at low pressure traveling towards the heart
what is the function of the capillaries
there are millions of them, exchange takes place here
they are very delicate
what is the function of arterioles
smaller arteries that control blood flow from arteries to the capillaries
what is the function of venules
smaller veins that return blood from capillaries to the vein
how do you remember the layers of blood vessels
Tough fibrous outer layer
Muscle layer
Elastic layer
Lumen
Thin inner lining / endothelium
what is the tough fibrous lining
resist pressure change within
what is the muscle layer
contract and relax which controls the blood flow
what is the elastic layer
it stretches and recoil which maintains the BP
what is the lumen
narrow and wide it is the central cavity where the blood flows
what is the thin inner lining
smooth to reduce friction
diffusion to capillaries
what is the structure and function of the arteries
arteries rapidly transport blood under high pressure away from the heart to tissue
-thick muscle layer
-thicker elastic layer
- stretches and recoils to maintain high BP propel blood and smooth pressure surges
-thick walls to resist bursting
-no valves
-lumen is narrow to control blood flow
what is the structure and function of arteriols
lower pressure than arteries
control blood flow
more muscle than arteries to control blood flow
thinner elastic layer than arteries yo lower BP
what is the structure and function of capillaries
exchange metabolic materials between blood and cells
no elastic or muscle cells
millions of them highly branched providing LSA
walls consist mostly endothelium lining creating SDP
have a narrow lumen so RBC have to squeeze flat against capillary
space between the lining cells which allows WBC to leave
RBC travel in single file slowly so time for diffusion RBC dont back up as millions
what is the structure and function of veins
deoxygenated blood at a low speed and pressure from capillaries to heart muscle
thin muscle layer
thin elastic layer
wide lumen
overall thickness is small
valves prevent backflow
what is osmosis
it is the diffusion of water from a dilute solution to a more concentrated solution through a partially permeable membrane
why is tissue fluid important
it surrounds every cell in the body, it is dynamic (always changing) depending on the body’s needs
TF supplies tissues with all it needs and in return receives CO2 and any other waste materials
it is where materials are exchanged
what does tissue fluid consist of
glucose, amino acids, fatty acids, ions in solution, oxygen
what happens to any excess TF
not all of the TF can return to the capillary so any excess is carried back via the lymphatic system
what is odema
a build up of tissue fluid that usually builds up in the feet and ankles as there is a lack of lymphatic vessels. as the heart beats faster there is higher infiltration so TF cannot drain into lymphatic vessels and remains into intercellular space
explain how TF forms and how it returns to the circulatory system
the contraction of the LV creates high hydrostatic pressure at the arterial end which forces small molecules e.g. glucose, water. large molecules remain in the capillary which decreases the water potential at the venous end so water moves back in via osmosis. the lymphatic system collects any excess TF which is returned to the blood
how does a lack of protein cause a build up of tissue fluid
the water potential in the capillary is higher as there is no protein so no water is removed from the capillary by osmosis
what is haemoglobin
haemoglobin is a protein with a quaternary structure , it is composed of 4 polypeptide chains (2 alpha, 2 beta)
what does each haemoglobin composed of
has 4 polypeptide chains (2 alpha 2 beta)
the 4 pp chains form an almost spherical shape
each pp chain contains a haem group
each haem group contain a ferrous group
where does haemoglobin load oxygen
HB loads oxygen in the lungs and unloads oxygen in respiring cells
what is affinity
a chemical attraction
what does it mean if HB has high affinity for oxygen
it takes up oxygen more easily and releases it less easily
in respiring cells HB have low affinity of oxygen so it readily unloads oxygen
what is partial pressure
a measure of the concentration of one gas in a mixture of gasses
in lungs PpO2 high
respiring cells PpO2 low
what is the role of HB in supplying oxygen to tissues
HB loads oxygen in the lungs to form oxyhaemoglobin at high PpO2 (almost fully saturated)
it unloads oxygen in respiring tissues at low PpO2, unbinding caused by CO2 concerntration
how is oxygen loaded
the shape of HB makes it difficult to load the first O2 at low PpO2
the haem group is the O2 binding site
the binding of the first O2changes the quaternary structure so changes the shape making it easier for the others to bind
small increase in PpO2 makes it easier for others to load
after 3rd binds 4th can bind but it is harder to due to probability majority of binding site occupied so less likely o2 will find empty binding site
the left shift (HB curve )
greater affinity of O2 for HB, loads o2 more readily but unloads o2 less readily
beneficial in lungs
the right shift
shifts to the right so lower affinity and loads o2 less readily but unloads more easily
beneficial in respiring cells
what is the relationship with CO2 concentration and O2
HB has reduced affinity for O2 in the presence of CO2 the greater
the conc of CO2 the more readily the HB releases its O2
how is CO2 unloaded
in respiring cells there is a high PpCO2 making the blood more acidic which lowers PH making the shape of HB change which has a lower affinity of O2 so releases it
what is the Bohr effect
higher rate of respiration leads to more CO2 produce in the tissues creating a lower PH which changes the shape so O2 is unloaded more readily so more O2 available for respiration
