Viruses Flashcards
What is the process of the lytic cycle?
-The virus binds to the cells complementry receptors
-Viral RNA is released into the cell
-The RNA replicates and protien synthisis occurs.
-New viral particals assemble
-The virus matures by going through the endoplamic reticulim and the golgi body.
-New virus is released from the cell.
What charcteristics does a virus have?
-It needs a host to survive.
-Acellar(not a cell).
-Genetic material can be DNA or RNA.
-Have no cytoplasm or organelles.
What is the process of the lysogenic cycle?
-They inject genetic material into the cell.
-The cell replicates their own and the viruses gentic material.
-they repeat this with many cells over and over.
-Then eneters the rest of the lytic cycle and infects many cells.
What features does a virus have?
-Has no nucules but a protien coat called the capsid to store RNA and DNA.
-Contains enzymes called transverse transcriptes which are used during DNA replication.
-Has a lipid envolope and protien molocules on surface to help attach to host receptors.
-Some virus cells have an inner matrix layer for protection.
What is HIV?
-Targets T-cells in immune system.
-Binds to the CD4 receptor on cells
-There are fewer cells to fight infection so infection and forms of cancer are more likely.
Why is there no treatment for HIV?
The virus muatates very quickly so it constantly changing meaning no available treatment.
What is the model answer for HIV replication?
-HIV attachment proteins complementary to the receptors on the helper T-cell.
-Virus nucleic acid (RNA/DNA) enters the cell.
-Reverse transcriptase converts RNA to DNA and inserted into the host genome.
-DNA is transcribed and the HIV capsid and enzymes are made by host cell ribosomes.
-Everything is assembled by host cells in RER and Golgi body into new virus protein.
-Virus is assembled and released.
How are viruses different to other cells?
-Not made of cells (acellular).
-Not alive (cannot respire, replicate).
-No metabolism.
