Gas exchange Part B Flashcards
Why are respiratory surfaces very thin and highly branched/folded?
Gills are thin tissue filaments that are highly branched and folded. … The folded surfaces of the gills provide a large surface area to ensure that the fish gets sufficient oxygen. Diffusion is a process in which material travels from regions of high concentration to low concentration until equilibrium is reached.
What are 2 reasons why skin breathing is not adequate for larger animals?
Larger animals don’t have enough skin surface area for diffusion to meet their metabolic needs
the skin is often specialised for other purposes
Why doesn’t gas exchange in insects involve the circulatory system?
don’t have a circulatory system to carry oxygen around their bodies. … Some air taken in never reaches the gas exchange surface, and not all of the air that has been to the gas exchange surface and lost its oxygen to the cells makes it out of the body.
How does PP of O2 and CO2 differ in blood in lung capillaries and tissue capillaries? How
does this difference affect diffusion of gases at each place?
PP - The larger the difference in PP of a gas between two areas, the faster the gas diffuses
CO2/O2 - the exchange of O2 and CO2 between body fluids and the environment. Gas exchange is necessary to provide O2 for cellular respiration and to remove CO2 created by this process
Explain how counter-current exchange maximizes the ability of fish gills to extract dissolved
O2 from water
increases the efficiency of gas exchange because O2 is transferred from the water to the blood along the entire length of the capillary (over 80% of O2 removed from water passing through gills). This occurs because the PP of oxygen in the water is always higher than in the blood it encounters
How does breathing differ in mammals and birds?
Bird lungs are smaller than those of mammals and don’t change volume during inhalation and exhalation. Breathing is not tidal – air only flows in one direction through the system regardless of whether the bird is inhaling or exhaling – so there is no mixing of old and new air.
