Exchange - Mass Transport In Animals Flashcards
What is the evidence that haemoglobin has a quaternary structure
Contains 4 polypeptide chains
What is made when haemoglobin combines with oxygen
Oxyhaemoglobin
Explain the term partial pressure
The amount of a particular gas in a mixture of gases or solution
Where is the partial pressure of oxygen highest in the body
In the alveoli capillaries in the lungs
Why is the partial pressure of oxygen lower in the tissues
Because of respiring tissues
Explain why the oxygen dissociation curve s sigmoid shaped
- Oxygen is complementary to the haemoglobin group
- Each time a molecule of oxygen attaches, haemoglobin changes shape
- This exposes ore of the next oxygen binding site
- This makes it easier for the next oxygen molecule to attach
What happens when the disassociation curve is shifted to the left
- Haemoglobin has a higher affinity or oxygen
- At the same partial pressure of oxygen, there is a greater percentage saturation of haemoglobin with oxygen
- So haemoglobin associates oxygen more readily and can be transported to tissues for aerobic respiration
What happens when the disassociation curve is shifted to the right when there is an increase in CO2 / active organism / increased respiration
- There is an increased rate of respiration
- This produces more carbon dioxide
- The curve shifts to the right (Bohr shift)
- This causes haemoglobin to have a lower affinity for oxygen
- At the same partial pressure of oxygen, there is a lower percentage of saturation of haemoglobin with oxygen
- So haemoglobin dissociates oxygen more readily at tissues for faster aerobic respiration
What happens when the dissociation curve is shifted to the left and altitude is present in the question
- Haemoglobin has a higher affinity or oxygen
- At the same partial pressure of oxygen, there is a greater percentage saturation of haemoglobin with oxygen
- So haemoglobin associates oxygen more readily and can be transported to tissues for aerobic respiration
- At altitude there is lower partial pressure of oxygen in the atmosphere
- So there will be a lower partial pressure of oxygen in the lungs
State the function of the valves
Prevents backflow of blood
Describe the three stages of the cardiac cycle
- Diastole (muscles are relaxed
) - Atrial Systole (atrial muscles contract)
- Ventricular Systole (ventricular muscles contracts)
Define the term cardiac output and what are the units
- The volume of blood pumped by one ventricle out of the heart in one minute
- dm3 min-1
Define the term heart rate
The rate at which the heart beats
Define the term stroke volume
Volume of blood pumped with each beat
What is the equation for cardiac output
Cardiac output = heart rate x stroke volume