Prokaryotic cells are a cell with no membrane boundorganelles
Viruses are not a prokaryotic cell as they are unable to reproduce without a host cell. They also don't have any membrane bound organelles within them.
Some bacterial cells contain a layer of mucilaginous slime called a capsule. This aids in protection
A bacterial cell does not contain a double helix of DNA it instead has circular DNA.
The cell wall is a physical barrier that protects against the entry of certain substances, mechanical damage and osmotic lysis.This is made of murein in a bacterial cell.
Circular DNA contains the genetic information for cell replication
A plasmid is a circular piece of DNA which can reproduce itself independently and can be transferred between bacteria. This may confer resistance to antibiotics
The flagellum is used for locomotion. Some species contain many and others contain none.
Features found in prokaryotic cells and not in eukaryotic cells:
DNA free cytoplasm
Murien in cell wall
No membrane bound organelles
Circular DNA with protiens
Every virus has a capsid. These control entry and exit out of the virus and helps keep DNA safe.
Both the matrix and lipid envelope are optional for viruses, these provide an extra layer of protection and is used to get inside the host cell
Attachment proteins are in all viruses. These attach to other cell receptors to enter the cell. These attach to the capsid if no envelope or matrix is present.
3 features found in all viruses:
Capsid
Attachment proteins
Genetic material
Viruses are acellular as they are not made up of a cell, have no membrane or cytoplasm
Antibiotics target cell walls which viruses lack, hence why they don't work on viruses
Virus replication:
Attach to the cell receptors and enters the cell. The envelope is lost at this point.
Uncoating (removes capsid) which releases the genetic material. Reverse transcription may happen at this stage
Intergrates into host DNA
Viral proteins are transcribed and translated
New viruses are assembled from the proteins
New viruses either bud off (lysogenic) or burst / lyse the cell (litic)
A bacterial cell is an example of a prokaryotic cell. A prokaryotic cell contains no membrane bound organelles.
The cell wall is a physical barrier which protects against the entry and exit of certain substance, mechanical damage and osmotic lysis. This is made of murein in a bacterial cell, and cellulose in a plant cell.
A capsule is the mucilaginous slime which is secreted by some bacteria. It aids in protection
Plasmids are circular pieces of DNA. They can reproduce independently and can be transferred between bacteria. They may confer resistance to antibiotics
Cytoplasm is a jelly like substance that contains enzymes and other soluble material.
Ribosomes synthesisepolypeptides. Bacteria contain the 70S type.
Flagellum is used for locomotion. Some species contain many whilst some contain none.
Viruses are not prokaryotic cells as they are unable to reproduce without a host cell. They also contain no organelles within them.
A capsid is contained in every virus. They control the entry and exit of the virus and keep DNA safe.
The matrix is optional for viruses. They also offer an extra layer of protection and help to enter the host cell.
The lipid envelope is optional for viruses. They also offer an extra layer of protection and enter the host cell.
Attachment proteins attach to the other cell receptors. These are found in all viruses and can attach to the capsid if no envelope is present.
Reverse transcriptase converts RNA back into DNA. These are contained in all RNA viruses.
Virus replication:
Attach to cell receptors and enter the cell. The envelope is then lost at this stage
Uncoating releases genetic material. Reverse transcription can also happen.
Intergrates into host DNA
Viral proteins are transcribed and translated by the host cell
New viruses are assembled from these proteins
The virus will either bud off (lysogenic) or burst the cell (lyslitic)
Describe how HIV replicates
Attachmentproteins attach to cell receptors to enter the cell
RNA will enter the cell, once attached
Reversetranscriptase converts the RNA into DNA
Viralproteins are produced and assemble a new HIV virus particle