3.2 transport in animals Flashcards
What is a double circulatory system
The blood flows through the heart twice to complete one full circuit
what is a single circulatory system
blood flows through the heart once to complete one full circuit
What are the advantages of a double circulatory system
Blood pressure can stay high
Deoxygenated and oxygenated don’t mix
What is an open circulatory system
The blood is not held/enclosed in vessels
What is a closed circulatory system
The blood is held and stays in the blood vessels
Advantages of a closed circulatory system
Higher pressure
More rapid delivery of oxygen and nutrients
More rapid removal of CO2
Disadvantages of open circulatory system
Blood pressure is low
Slow flow
Circulation of blood may be affected by body movements
what circulartory system is found in insects
open
what circulatory system is found in fish
closed
name the layers in blood vessels
Lumen
Endothelium
Elastic fibres
Smooth muscle
Collagen fibres
purpose of the endothemlium
Inner layer lining of the blood vessel
reduces friction with flowing blood
purpose of collagen fibres
helps strengthen the walls
Function of arteries
Carry blood away from the heart
(Aorta , pulmonary artery)
Structure of arteries and the benefit
Small lumen
Small layer of elastic tissue - help to stretch and recoil
Large layer of muscle
Relatively large layer of collagen - withstand high pressure
What are arterioles
Small blood vessels that that distribute blood from an artery to capillaries
Structure of arterioles
Later of smooth muscle which contracts to divert/control blood flow
What are capillaries
Exchange of materials between the blood and tissue fluid
Structure of capillaries
Lumen is narrow
Single layer of flattened endothelium cells
What are veins
Carry blood back to the heart
Structure of veins
Large lumen
Thinner layers of collagen, smooth muscles, elastic fibre
Valves
What is blood
Fluid used to transport materials around the body
What is tissue fluid
Fluid that surrounds cells and tissues
Contains very few wbc and proteins
What is lymph
Fluid held in the lymphatic system
How does hydrostatic pressure form tissue fluid
Near the arteriole end = higher hydrostatic pressure in capillaries to tissue
difference forces blood plasma out of capillary into spaces = forms tissue fluid
What is hydrostatic pressure
The pressure a fluid exerts when pushing against sides of vessels
What is oncotic pressure
The pressure created by the osmotic effects of the solutes
How does hydrostatic and oncotic pressure move fluids
The net result of these forces creates a pressure to push fluid out of arterial end and back in at the venule end
name the structures of the heart
L/R atria
L/R ventricle
aorta
vena cava
pulmonary vein/ artery
atrioventricular valves
semilunar valves
septum
coronary arteries
what side of the heart pumps oxygenated blood and how is it suited to this
the left side
thicker walls
what side of the heart pumps deoxygenated blood
the right side
what tissue is the heart made out of
cardiac muscle
function of coronary arteries
supplies blood to the heart
aorta
carries oxygenated blood out of the heart and to the body/ tissues
vena cava
brings/ returns deoxygenated blood to the heart
pulmonary vein
oxygenated blood brought back to the heart from the lungs
pulmonary artery
deoxygenated blood away from the heart to the lungs
septum
wall of muscle seperating heart chambers
atrioventricular valves
bicuspid (left side, 2) and tricuspid (right side, 3) valves
semilunar valves
prevents blood returning back into the heart after leaving
what is the cardiac cycle
the sequence of events/coordinated sequence in one full beat of the heart
what happens during ventricular systole
right and left ventricle pump together to push blood up out of the arteries
what happens during diastole
muscular walls of all chambers relax to allow blood to flow in through veins
what happens during atrial systole
right and left atria contract pushes blood into ventricles
what do valves do
keeps blood flowing in the same direction
how do atrioventricular valves work during systole and diastole
after systole - pressure in ventricles decreases below pressure in atria - blood pushes valves open and moves into ventricles - blood now higher in ventricles so tries to move back up - valves close
how do semilunar valves work during systole
blood pressure in ventricles rises - rises above pressure in arteries - valves open
how do semilunar valves work during diastole
ventricle size rturned/elastic recoils - pressure drops in ventricles - blood pushed back towards so valves pushed closed
what does myogenic mean
heart muscle initiates its own beat
where is the pacemaker found
walls of right atrium
state the stages of controlling a heartbeat
SAN
atrial systole
AVN
bundle of his
purkinji fibres
ventricular fibres
what is the SAN and what does it do
sino atrial node
generates electrical activity/ ave of excitation
how doe the wave of excitation cause atrial systole
spreads out over atria walls causes it to contract
what is the AVN and what does it do
atrio ventricular node
delays the wave of exitation
allows atria to empty
what is the role of bundle of his
passes impulse down the septum
what is the role of purkinje fibres
impulse is taken and spread out over walls of ventricles (ventricular systole)
what is an electrocardiogram
trace that records electrical activity of the heart
what is bradycardia and tachycardia
brady= slow heart rate
tach = fast
what is atrial fibrillation
atria beats more frequently then ventricles
what is ectopic heartbeat
heartbeat occurs early , felt as if one is missed
define affinety
strong attraction/ how much a substance binds to another
what is haemoglobin
protein that transports oxygen in erythrocytes
what makes up oxyhaemoglobin
haemoglobin and oxygen
what is the association of oxygen
in the lungs oxygen diffuses into plasma and enters rbc
what is the dissociation of oxygen
oxyhaemoglobin dissociates oxygen/ releases it
what does the haemoglobin dissociation curve show
in low ppO2 = little association of oxygen
as ppO2 rises = more oxygen associates to haemoglobin
explain conformational change in haemoglobin
as pp of oxygen rises - diffusion gradient rises - 1 oxygen can associate easily - causes slight change in haemoglobin shape - more oxygen can bind easily
how does the change in haemoglobin shape change the shape of the curve
more oxygen is associating so curve gets steeper
what is fetal haemoglobin
haemoglobin found in the fetus
describe fetal hB affinety for oxygen
higher affinety for oxygen then adult haemoglobin
describe the effect of fetal hB on the dissociation curve and why
moves to the left
more oxygen has to associate to haemoglobin iin environment where adult haemoglobin can dissociate it
Name the 3 ways co2 can be transported
Directly in the plasma
Forming carbaminohaemoglobin
Forming hydrocarbonaye ions
Explain all the process that happens when co2 diffuses into a rbc
Combines with water = carbonic acid
Carbonic acid dissociates to releases H+ ions and hydrogen carbonate HCO3- ions
H+ ions bind with Hb to form haemoglobinic acid
HCO3- ions diffuse out of the rbc so chloride ions diffuse in
what is the chloride shift
movement of chloride ions into erythrocytes to balance the charges as HCO3- leaves
what is the purpose of forming haemoglobinic acid
acts as a buffer as prevents H+ ions building up
how does the pH in red blood cells change
pH decreases/ becomes more acidic as H+ ions build up
what is the bohr effect
the effect that increasing concentration of carbon dioxide has on haemoglobin
explain the bohr shift
haemoglobin dissociation curve shifts to the right - as more CO2 so less O2 saturated with oxygen so more oxygen dissociates
explain why the bohr shift happens
CO2 enters the rbc - carbonic acid formed - dissociates to produce H+ = lowers the pH, more acidic = alters tertiary structure = reduced affinety for oxygen = more dissociates
