Which structures make it immediately possible for the exchange of gases to occur in a plant?
a.
stems and petals
b.
stomata
c.
roots and petals
d.
leaves and flowers

Which of the following types of rock would most likely contain a fossil? slate granite lava rock limestone

How do the evolutionary chart and the video support the claim that all living things are made up of cells?

Lactase is essential for digesting lactose in milk. this enzyme is specific for this sugar. why? molecules and active sites vary in size; only properly sized molecules can fit.there is a precise compatibility between the active site and the lactose molecule.specificity refers to the action of the enzyme, such as hydrolysis, and relatively few molecules can be hydrolyzed.reaction-specific enzymes assume a fit by folding around the most numerous substrate molecules.