Chapter 7- Mass transport Flashcards
What is haemoglobin
a group of chemically similar molecules found in a wide variety of organisms
Structure of haemoglobin
- primary structure is the sequence of AA’s in the 4 polypeptide chains
- secondary structure in which polypeptide chains coil into a helix
- tertiary structure where polypeptide chains fold into a precise shape
- quaternary structure where all 4 polypeptide chains are linked together to form an almost spherical molecule
What is loading/association
process by which haemoglobin binds with oxygen
What is unloading/dissociation
process by which haemoglobin releases its oxygen
what are some properties haemoglobin must have to efficiently transport oxygen
- be able to readily associate with oxygen
- readily dissociate from oxygen
What is an oxygen dissociation curve
- s shaped curve
- shows a relationship between the saturation of haemoglobin with oxygen and the partial pressure of oxygen
Describe the shape of the first part of an oxygen dissociation curve
- slow increase to begin as its difficult for oxygen to bind
Describe the shape of the second part of the oxygen dissociation curve
- its easier for oxygen to bind as after the first oxygen binded, it changed the quaternary structure of the haemoglobin
- results in a steeper angle of the curve
Describe the shape of the third part of an oxygen dissociation curve
- -the curve starts to flatten out as there is only a smaller increase in partial pressure because there is becoming less area for the oxygen to bind to
How does carbon dioxide effect haemoglobin
CO2 reduces affinity for oxygen
Describe the structure of the heart
- two pumps
- left pump deals with oxygenated blood
- right pump deals with deoxygenated blood
- both sides have an atrium which is a thin- walled and elastic and stretches as it collects blood
- both sides have ventricles which are thicker muscular walls as it has to contract strongly to pump blood
What are the valves called and what are they used for
- two valves
- left atrioventricular (bicuspid) valve
- right atrioventricular ( tricuspid) valve
- the use is to prevent backflow of blood
What are the two stages of the cardiac cycle
- contraction ( systole)
- relaxation (diastole)
Describe diastole
- blood returns to the atria of the heart through the pulmonary vein (from the lungs) and the vena cava (from the body)
- blood flows into the ventricles when the pressure gets higher making the atrioventricular valves to open
Describe atrial systole
- contraction of atrial walls force remaining blood in the atria to move into the ventricle