Unlike a typical animal cell, this plant cell has an angular shape. the shape of a plant cell is due, mostly, to the presence of the
a. nucleus.
b. cell wall.
c. chloroplast.
d. cell membrane.

The right answer is cell wall.

The wall surrounds all the plant cells. It gives an angular aspect to the plant (pentameric, hexameric).

In terrestrial plants, the strongest component of the complex cell wall is a large carbohydrate called cellulose, while those of algae are usually composed of glycoproteins and polysaccharides. However, some species of algae may have a cell wall formed of silicic acid and the seaweed walls are characterized by sulphated polysaccharides which could play a role in the adaptation of the plant to the marine environment.

in a word, a scientific question is testable. a testable question is one that asks about objects, organisms or events found in the world around it

enzyme active site and substrate specificity

enzymes bind with chemical reactants called substrates. there may be one or more substrates for each type of enzyme, depending on the particular chemical reaction. in some reactions, a single-reactant substrate is broken down into multiple products