Ascientist was observing an unknown slide under an electron microsocope; he found a cell without a well-defined nucleus but with a thick cell wall and ribosomes. what type of cell could it be?
prokaryotic
eukaryotic plant cell
eukaryotic animal cell

Temperatures in ponds and lakes vary by season. select the best answer from the choices provided t f

In a lab, scientists grew several generations of offspring of a plant using the method shown. what conclusion can you make about the offspring? a. they formed from meiosis and mitosis. b. they have half the number of chromosomes as their parent. c. they have low genetic variability among them. d. they will be able to reproduce only after they grow flowers.

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.