Students testing the effects of solute concentration in soil on plant transpiration noticed a significant decrease in transpirat
ion when abscisic acid was used as the solute. Even at molar concentrations less than 0.2 M, transpiration seemed to stop almost completely. a) Make a claim as to which structural and/or physiological component of transpiration is affected by the presence of abscisic acid.
b) Explain the reasoning that supports your claim.
Drought stress can also cause stomata to close. A hormone called abscisic acid (ABA) is produced in roots and leaves in response to water deficiency and signals guard cells to close stomata. This response reduces wilting but also restricts CO2 absorption, thereby slowing photosynthesis. ABA also directly inhibits photosynthesis. Water availability is so tied to plant productivity not because water is needed as a substrate in photosynthesis but because freely available water allows plants to keep stomata open and take up more CO2.
abscisic acid (ABA): A plant hormone that slows growth, often antagonizing the actions of growth hormones. Two of its many effects are to promote seed dormancy and facilitate drought tolerance.
Red blood cells have a flattened disk shape. This relates to their function as this shape increases the surface area to volume ratio for better gas exchange.
Definitely true, because it is in a constricted space and you end up breathing more of it in, causing more harmful effects than if you were smoking the cigarette yourself
