A2 Gas Exchange Flashcards
Do small or big organisms have a large surface area to volume ratio?
Small
What increases when surface area to volume ratio increases?
Oxygen uptake increases
What are endotherms?
Organisms that control body temperature internally
What replaces heat loss?
Respiration
What happens to the heat loss of an organism with a high surface area to volume ratio compared to an organism with a low surface area to volume ratio?
Organisms with a high surface area to volume ratio lose heat at a higher rate , so there is a higher rate of respiration to replace the heat lost. Respiration is a metabolic reaction , oxygen uptake gives a proxy for metabolic rate
What is counter current flow?
When blood and water flow in opposite directions through and over the lamellae
What is an efferent vessel?
A vessel that goes outwards and away from the gills
What is an afferant vessel?
A vessel that goes towards the gills
Describe and explain the advantage of the counter- current principle in gas exchange in fish gills.
The counter current principle is when the blood and water flow in opposite directions through and over the lamellae. This means that there is a constant concentration gradient maintained along the entire lamellae and the oxygen concentration between the water and blood does not reach equilibrium.
What is a spiracle?
The opening of an insect’s body
What in an insect’s gas exchange structures gives a large surface area?
Highly branched tracheoles
What in an insect’s gas exchange structures gives a high concentration gradient?
Cells are constantly respiring and abdominal pumping ( a form of ventilation)
What in an insect’s gas exchange structures gives a short diffusion distance?
Very thin tracheole walls
What in a fish’s gill gives a large surface area?
Highly branched gill filaments with many lamellae
What in a fish’s gill gives a high concentration gradient?
Ventilation of water and blood flow
