Questions and Answers

State that cells use ATP from respiration for energy-requiring processes

state that all viruses are non-cellular structures with a nucleic acid core (either DNA or RNA) and a capsid made of protein, and that some viruses have an outer envelope made of phospholipids

compare the structure of a prokaryotic cell as found in a typical bacterium with the structures of typical eukaryotic cells in plants and animals

outline key structural features of a prokaryotic cell as found in a typical bacterium, including: • unicellular • generally 1–5 µm diameter • peptidoglycan cell walls • circular DNA • 70S ribosomes • absence of organelles surrounded by double membranes

How to draw cells from microscope slides and photomicrographs

define resolution and magnification and explain the differences between these terms, with reference to light microscopy and electron microscopy

use an eyepiece graticule and stage micrometer scale to make measurements and use the appropriate units, millimetre (mm), micrometre (µm) and nanometre (nm)

calculate magnifications of images and actual sizes of specimens from drawings, photomicrographs and electron micrographs (scanning and transmission)