Unit 3 Mass transport in Animals Flashcards
Describe what is meant by haemoglobin.
- Haemoglobins are groups of proteins found in different organisms
- Haemoglobin is a globular protein with a quaternary structure
- 4 haem groups with o2 bind to so can be transported around the body
Name 2 factors affecting oxygen-hemoglobin binding.
Partial pressure/concentration of oxygen/co2
Saturation of haemoglobin with oxygen
Define partial pressure and affinity
Partial pressure - a measure of the concentration of oxygen/carbon dioxide concentration in a cell
Affinity - Strength between 2 molecules
Describe the relationship between partial pressure of oxygen and haemoglobin saturation on the oxyhaemoglobin dissociation curve.
(HIGHER ON GRAPH)
More saturation = Loaded with oxygen
- Oxygen loads onto haemoglobin regions with a high partial pressure of oxygen e.g alveoli
(LOWER ON GRAPH))
Less saturation = Unloaded oxygen
- Oxyhaemoglobin unloads oxygen in regions with a low partial pressure of oxygen e.g respiring tissues
Describe cooperative binding and the shape on the oxyhaemoglobin dissociation curve.
(Same shape AS PREVIOUS)
- Cooperative nature due to
- Haemoglobin changing quaternary shape when first oxygen binds
- Shape change makes it easier for further oxygens to bind as another haem group available
Describe the Bohr effect and the effect on oxyhaemoglobin disassocation curves
- The Bohr effect is when a high carbon dioxide concentration causes oxyhaemoglobin curve to shift to right
- Causes haemoglobins affinity for oxygen to decrease by decreasing blood pH
- So haemoglobins shape changes slighly
Explain why oxygen binds to haemoglobin in lungs
- Partial pressure of oxygen is high
- Partial pressure of CO2 is low in lungs so affinity increases
Describe how hemoglobin is different in different organisms.
AND EXAMPLE
(SHIFTS TO LEFT ON GRAPH)
- Organisms living in low concentrations of oxygen have haemoglobin with a higher affinity for oxygen
(SHIFTS TO RIGHT ON GRAPH)
- Organisms that are very active have higher metabolism so more oxygen demand for respirtation and haemoglin with lower affinity for oxygen so more unloading
- Fetal haemoglobin has higher affinity for oxygen at same partial pressures so fetus haemoglobin can load oxygen off from mother haemoglobin
Describe the general pattern of blood circulation in a mammal.
Double circulatory system - Blood passes through the heart twice in each circuit
LUNGS
↑ ↓
↑ ↓
HEART
↑ ↓
↑ ↓
BODY
- In 1 circuit heart delivers blood to lungs
and in other circuit blood delivered to rest of body
Describe the blood vessels leaving the heart, kidney and lungs
LUNGS
- Pulmonary artery - Pulmonary vein
HEART
- Vena cava - Aorta
KIDNEYS
- Renal vein - Renal artery
DEOXYGENTED BLOOD OXYGENATED BLOOD
Name all the parts of the heart including chambers, vessels and valves.
Relate the structure of the ATRIUM to their function.
2 ATRIUM
- Thin and elastic muscular walls so can stretch when filled with blood
Relate the structure of the VENTRICLES to their function.
2 VENTRICLES
RIGHT VENTRICLE = pumps blood to lungs
- Thick muscular walls but less thick than left ventricle so less pressure
- To prevent damage to capillaries in lungs
LEFT VENTRICLE = pumps blood to ROB
- Thicker muscular wall than right ventricle as higher pressure required so bigger contractions
- To ensure blood reaches all cells/respiring cells in body
Describe the veins and arteries which carry blood away and to the heart.
Vena cava = carries deoxygenated blood from body to heart
Pulmonary artery = carries deoxygenated blood from heart to lung
Pulmonary vein= carries oxygenated blood from lungs to heart
Aorta= carries oxygenated blood from heart to ROB
Describe the function of valves
- To prevent back flow of blood
- By only opening when pressure is higher behind the valve
Describe the blood vessels Arteries - veins
CORONARY ARTERIES CARRY BLOOD TO HEART.
ALL ARTERIES CARRY OXYGENATED BLOOD not pulm.
- Arteries carry blood away from heart into arterioles
- Arterioles smaller than arteries & connect to capillaries
- Capillaries connect arterioles to veins
- Veins carry blood into heart
Describe how an artery is adapted to its function
Artery
- Thicker walls than veins to prevent vessels bursting due to high blood pressure
- Inner endothelium folded to allow stretching
- Smaller lumen than veins
Describe how an arteriole is adapted to its function
Arteriole
- Thinner wall thickness as lower pressure than artery
Describe how a vein is adapted to its function
Vein
- Relatively thin walls so can be flattened helping flow back to heart
- Contains valves to prevent backflow
Describe how a capillary is adapted to its function
Capillary
- Walls are one cell thick to provide short diffusion pathway
- Narrow diamater to slow blood flow
Describe the what happpens in the cardiac diastole
- Atria & ventricular musles relaxed
- Blood enters atria via pulmonary vein/vena cava which causes increase in pressure in atria
- Which pushes blood into ventricles & AV valves to open
Describe the what happpens in atrial systole.
- Atria muscular walls contract to increase pressure more pushing remaining blood to ventricles
- Ventricular muscle walls are relaxed
Describe the what happpens in Ventricular systole
- Ventricle muscle walls contract increasing pressure even more than atria
- Which closes AV valves to prevent backflow & opening semi-lunar valves
- Blood pushed out of ventricle into arteries(aorta/pulmonary artery) at higher blood pressure
Give the cardiac output equation
Cardiac output = Heart rate x Stroke volume
min-1 dm3
Describe what is meant by tissue fluid
- Fluid containing glucose, amino acids, oxygen, water poteins which bathe tissues
Describe how tissue fluid is formed
(ULTRAFILTRATION)
- Capillaries smaller diamater than arterioles results in high hydrostatic pressure compared to tissue fluid so
=Water, Glucose, Amino acids pushed out
are forced out
- Red blood cells, platelets and large proteins remain in capillary as too big
Describe how tissue fluid is reabsorbed
- Capillaries smaller diamater than arterioles results in high hydrostatic pressure compared to tissue fluid so water forced out
- Large Proteins remain in capillary as too big which reduces water potential of blood
- Towards venule end of capillaries hydrostatic pressure lower than in tissue fluid due to loss of liquid
- Water therefore re- enters capillaries by osmosis
- Excess tissue fluid absorbed by lymphatic system
