Prokaryotic Cells And Viruses Flashcards
What is the difference between a eukaryotic cell and prokaryotic cell?
Eukaryotic cells are larger and have a nucleus bounded by nuclear membranes, whereas prokaryotic cells are much smaller and have no nucleus.
What is some DNA in the form of in prokaryotic cells?
Circular strands called plasmids.
What ribosomes do prokaryotic cells have?
(70s) they are smaller.
What is the cell wall made of in prokaryotic cells?
Murein.
What do prokaryotic cells sometimes have?
An outer mucilaginous layer called a capsule.
What do prokaryotic cells not have?
Chloroplasts.
What cells don’t have membrane-bounded organelles?
Prokaryotic cells.
What is DNA associated with in eukaryotic cells?
Proteins called histones.
What are there none of in eukaryotic cells?
Plasmids and a capsule.
What is present in eukaryotic cells?
Chloroplasts and membrane-bounded organelles.
What are the ribosomes in eukaryotic cells?
(80s) they are larger.
What are cell walls made of in eukaryotic cells when present?
Mostly cellulose or chitin in fungi.
Where do bacteria occur?
In every habitat in the world.
What size are bacteria?
From 0.1 to 10 micrometers in length.
What is bacteria’s success rate due to?
Their small size.
What is the cell wall made of in bacteria?
Murein.
What is murein?
A polymer of polysaccharides and peptides.
What do bacteria secrete around the cell wall and why?
A capsule of mucilaginous slime to further protect themselves.
What ribosomes do bacteria cells have and what do they do?
(70s), synthesise proteins.
What is the role of the cell wall in bacteria cells?
As a physical barrier that excludes certain substances and protects against mechanical damage and osmotic lysis.
What is the role of a capsule in bacteria cells?
Protects bacterium from other cells and helps groups of bacteria to stick together for further protection.
What is the role of the cell surface membrane in a bacteria cell?
To act as a differential,y permeable layer, which controls the entry and exit of chemicals.
What do bacteria store food as?
Glycogen granules and oil droplets.
What is the genetic material in in bacteria?
A circular strand (loop) of DNA.
What is the role of circular DNA in bacteria?
Possesses the genetic information for the replication of bacteria cells.
What is the role of plasmids in bacteria cells?
Possesses genes that may aid the survival of bacteria in adverse conditions, such as enzymes that break down antibiotics.
What are plasmids used as in genetic engineering?
Vectors (carriers of genetic information)
What are the features of a bacterial cell?
Cell wall, cell surface membrane, plasmids, ribosomes, capsule, cytoplasm, genetic material, and flagellum.
What are viruses?
Acellular, non-living particles.
What size are viruses?
20-300 nanometers.
What do viruses contain?
Nuclei acids such as RNA or DNA as genetic material.
Where can viruses only multiply?
In living host cells.
What is the nuclei acid enclosed within in a virus?
A protein coat called the capsid.
What are some viruses further surrounded by?
A lipid envelope.
What do the lipid envelope or capsid have on them?
Attachment proteins.
What do attachment proteins on viruses allow?
Viruses to identify and attach to a host cell.
What features does a virus have?
Genetic material, attachment proteins, a capsid, a lipid envelope (sometimes), a matrix, and the enzyme reverse transcriptase.
