Question

1. cells vary in __________ and __________. *

proteins endoplasmic reticulum cell wall
size life processes cell membrane
chlorophyll nucleus energy
cells chloroplasts shape
your answer

Explanation:

In the study of cells (a topic in Biology, a subfield of Natural Science), cells are known to vary in their size (how big or small they are) and shape (their physical form or structure). Other options like proteins, organelles (endoplasmic reticulum, nucleus, etc.), chlorophyll, life processes, energy, or cell parts (cell wall, cell membrane) don't fit the context of "varying in" as a general characteristic of cells in the same way size and shape do.

Answer:

size, shape