Name some ways prokaryotic cells differ from eukaryotic cells:
-Cytoplasm that lacks membrane-bound organelles
smaller ribosomes
-No nucleus; instead they have a single circular DNA molecule that is free in the cytoplasm and is not associated with proteins
-A cell wall that contains murein, a glycoprotein.
Some have:
-Plasmids
-Flagella
-Capsule surrounding cell
What are plasmids?
Small loops of additional DNA often containing advantageous alleles. Bacteria can swap plasmids.
What is a capsule?
Some prokaryotes (e.g. bacteria) are surrounded by a final outer layer known as a capsule. This is sometimes called the slime capsule. It helps to protect bacteria from drying out and from attack by cells of the immune system of the host organism
Describe the structure of viruses:
They are relatively simple in structure; much smaller than prokaryotic cells (with diameters between 20 and 300 nm). Structurally they have a nucleic acid core (their genomes are either DNA or RNA, and can be single or double-stranded) and a protein coat which is called a capsid. They also have attachment proteins in a lipid envelope.
