Gas Exchange Flashcards
What is BMR?
Basal Metabolic Rate, is the rate of energy expenditure per unit time by endothermic animals at rest
What processes are accounted for in BMR?
Breathing, blood circulation, controlling body temperature, cell growth, brain and nerve function, contraction of muscles
What are endothermic animals?
maintains stable body temperature, must generate their own body heat sometimes. = Higher metabolic rate therefore must eat more
What are ectothermic animals?
body temperature changes with the environment
What is ventilation?
bringing gases to or from a gas exchange surface; usually a mechanical process; only happens in some multicellular organisms.
What is gas exchange?
process by which gases cross a gas exchange surface; happens in all organisms.
What is respiration?
metabolic pathway that releases chemical energy from food molecules; happens in all organisms.
Birds gas exchange system?
lungs and air sacs (air sacs allow for one-way flow of gases
What is counter current flow?
The movement of water and blood in opposite directions across gill lamellae.
What do gill filaments do?
create a larger surface area for increased gas absorption and exchange
Why do fish have a one-way flow system?
it requires less energy so is more efficient because flow does not have to be reversed as water is more dense
Buccal ventilation involves what?
using cheek muscles to force water over gills
Ram ventilation involves what?
swimming with mouths open forcing water over gills
How does Buccal Ventilating work to take in water? (opposite to force out water)
mouth opens, operculum closes, floor to mouth is lowered, volume of buccal cavity increases, pressure inside the buccal cavity decreases, water flows from area of high pressure outside mouth to area of low pressure inside mouth
What do insects have that can allow them to carry out efficient gas exchange?
spiracles to trachea to tracheoles to muscles
Features of a mammalian gas exchange system?
nasal cavity, trachea, bronchus, bronchioles, alveoli
What is the thorax?
Airtight and protected compartment encompassing the chest cavity, diaphragm, lungs, heart
What is the function of the thorax?
Protects delicate (single cell) exchange surface, generates pressure gradient in ventilation
What is the pleural membranes?
Membranes which cover the lungs and line the thorax
What is the function of the pleural membranes?
Contain fluid which prevents friction between lung and chest cavity as lungs move and expand
What is the diaphragm?
Dome shaped sheet of muscle, separating thorax and abdomen
What is the function of the diaphragm?
Contracts to expand volume of chest cavity during inhalation
What are the rib and intercostal muscles?
Bones which surround the thorax, muscles between them (internal and external intercostal muscles)
What is the function of the rib and intercostal muscles?
Provide protection and structure, external IM contract in inhalation (bringing CV up and out), internal IM contract in exhalation (pulling CV down and in)
What is breathing?
The process of moving air into and out of the lungs
What is metabolism?
Sum of the chemical reactions that take place within a cell that provide energy for vital processes and for synthesizing new organic material
