Adaptations For transport in animals Flashcards
(28 cards)
Explain the significance of the effect of an increased partial pressure of carbon dioxide for respiring muscle tissues
Reduced affinity of haemoglobin for oxygen
More oxygen is released
Why was an increase in the volume of gas inhaled or exiled lead to a decrease in the partial pressure of carbon dioxide of blood in alveoli capillaries?
Carbon dioxide is removed faster so an increased diffusion gradient from blood into the alveoli
A form over than the boer effect in which carbon dioxide is carried around the blood
Dissolved in plasma
Chloride shift
Chloride ions enter into the red blood cells in exchange for hydrogen carbonate ions
One to one exchange
To maintain electrochemical neutrality in the red blood cells
Pressure change in systematic circulation
Pressure increases in the aorta due to ventricular systole
High-pressure is needed to pump body for a long distance
Pressure decreases in the arteries due to diastole
High pressure is maintained due to elastic recoil of artery walls
Pressure decreases in arterial due to frictional resistance
Pressure decreases in capillaries, which is due to tissue fluid formation
Low pressure in capillaries necessary for diffusion
Blood flow in veins due to massaging effect of skeletal muscles
Pressure change in pulmonary circulation
Pressure increase in pulmonary artery due to ventricular systole
Lower pressure than systematic due to shorter distance only to the lungs
Pressure decrease in pulmonary arteries due to diastole
Pressure in capillaries is lower than systematic to prevent tissue fluid formation in the alveoli
Why is double circulation considered to be more efficient than single circulation in fish
Pressure is lost when blood passes through gill capillaries
This means that blood flow through the systematic circulation of a fish is slower
Double circulation maintains high pressure in systematic circulation in order to meet the high metabolic demands of a mammal
The events occurring during the p wave
SAN generates electrical impulses
These cause depolarisation of atria which causes contractions of atrial systole
The events occurring during the QRS complex
AVN transmits electrical impulses
These past through the bundle of his
Depolarisation of the ventricles causes contraction of ventricular systole
What events occurred during the T wave?
Repolarisation of the ventricles which causes ventricular distole
Which region of the conducting tissue of the heart is affected by a first-degree heart block?
The AVN
Structure of a red blood cell is related to its function
Bio concave which increases diffusion
Biconcave shape so has a short diffusion path
No nucleus so more space for haemoglobin
Name the vessel that removes excessive tissue fluid
Lymph capillary
Why would fluid accumulate in the tissues of a person whose diet is poor in protein?
Not enough protein in the blood which raises water potential of plasma
This reduces the water potential gradient so less water is reabsorbed by osmosis
The roles of the SAN AVN bundle of his & purkyne fibres in controlling the cardiac cycle
The SAN is the pacemaker causing atrial systole
The AVN delays the excitation
The bundle of his transfers excitation to purkyne fibres
Excitation passes up the purkyne fibres causing the ventricles to contract from the Apex upwards
What effect would an irregular QRS complex and T wave have on the cardiac cycle?
Ventricular systole and diastole would not occur regularly
Blood remains in the ventricles and does not enter the arteries
Haemoglobin affinity
Haemoglobin has a high affinity for oxygen at high partial pressure of oxygen (lungs)
Therefore, it associates with oxygen in the lungs
Haemoglobin has a low affinity for oxygen at low partial pressure of oxygen (tissues)
Dissociates with oxygen in the tissues
Haemoglobin of naked mole rat on dissociation curve
Has a haemoglobin with a high affinity for oxygen
Haemoglobin can become fully saturated with oxygen at a lower partial pressure of oxygen than human haemoglobin
Dissociation curve on hummingbirds who are active
Have a higher rate of respiration which produces more carbon dioxide and increases the partial pressure of carbon dioxide
Haemoglobin with a lower affinity oxygen
This means it dissociates or unloads more oxygen to the tissues
How do people become adapted to living at very high altitudes?
Haemoglobin has an increased affinity for oxygen
Why does a parasitic worm have an oxygen dissociation curve to the left?
Low concentration of oxygen in the gut so it has a higher affinity for oxygen
Why does the hydrostatic pressure decrease as the blood travels along the capillaries?
Water is lost from the capillaries so increased resistance
Why does osmotic pressure remain constant as the blood travels along the capillaries?
Osmotic pressure caused by plasma proteins
They are too large to leave the capillary
Why is a lymph vessel necessary?
Hydrostatic pressure is greater than osmotic pressure for the majority of the capillary so more fluid is forced out then reabsorbed meaning that excess tissue fluid is absorbed
