6. Exchange Flashcards
Name three components of the tracheal system in insects?
spiracles, trachea, tracheoles
Name two components of the gas exchange system in gills of a fish?
gill filaments, lamelle
By what principle do fish exchange gases in their gills?
counter current mechanism
define dicotyledonous?
a plant in which the seed has two embryonic leaves
name three components of the leaves of dicotyledonous plants involved in gas exchange?
stomata, guard cells, mesophyll cells
how do xerophytic plants limit water loss?
waxy cuticle hairy leaves curled shape sunken stomata in pits reduced SA:vol ratio of leaves
how do insects balance the need for gas exchange with the need to limit water loss?
in dry conditions spiracles close to limit water loss
what reaction occurs in which larger molecules are broken down into smaller ones?
hydrolysis
why must molecules be made smaller to allow digestion?
to allow them to pass through cell membranes
what two enzymes break down carbohydrates?
amylase and membrane bound dissacharidases
which enzyme breaks down lipids?
lipases
explain how bile salts aid with the digestion of lipids?
bile salts emulsify lipids into micelles.
This increases surface area for lipases to act upon
which three enzymes break down proteins?
endopeptidases
exopeptidases
depeptidises
How do endopeptidases carry out their function?
endopeptidases attack anywhere along polypeptide chain, apart from the ends.
how do exopeptidases carry out their function?
attack ends of polypeptide chain
how do depeptidises carry out their function?
break down dipeptides into single amino acids.
where in mammals does absorption occur?
illeum
what mechanism permits absorption of amino acids and monosaccharides?
co-transport
state the equation for cardiac output?
heart rate x stroke volume
what is digestion?
physical breakdown and chemical digestion
what type of digestion does salivary amylase aid?
hydrolysis of starch to maltose
where is salivary amylase produced?
produced by the salivary glands
what feature allows salivary amylase to maintain a neutral PH?
contains mineral salts
what type of digestion does pancreatic amylase aid?`
hydrolysis of starch to maltose