HIV and AIDS Flashcards
What does HIV stand for
Human immunodeficiency virus
What type of virus is HIV
A retrovirus
Can HIV survive outside of human body
No
How is HIV transmitted
By direct exchange of body fluids
In what ways can HIV be transmitted
Sexual intercourse, blood donation, sharing of needles used by intravenous drug users, from mother to child across placenta, from mother to child through breast milk
What components are contained within the structure of HIV
Two RNA strands, Proteins, A protein coat (capsid), a viral envelope consisting of a lipid bilayer and glycoproteins and attachment proteins.
What are attachment proteins on HIV for
To attach to cells and infect them
What does HIV do when it enters the bloodstream
Infects helper T cells
Why can’t lymphocytes and antibodies break down HIV
HIV avoids being recognised by repeatedly changing its protein coat
What is the process of HIV multiplying
Viral RNA enters host cell, viral reverse transcript enzymes produce a DNA copy of the viral RNA, the DNA copy is inserted into the chromosomes of the host cell, each time host cell divides it copies the viral DNA, the infected cells remain normal as the viral DNA is inactive. Individual is now HIV positive.
What happens to viral DNA after a few years of being within host cells
Viral DNA becomes active
What happens when the viral DNA of cells becomes active
It takes control of the helper T cells, more HIV particles are produced, causes helper T cells to die, as a result - thousands of new HIV particles are released which are able to infect other helper T cells.
What happens as HIV gradually reduces the number of helper T cells
B cells are no longer activated , no antibodies are produced
What are the results of antibodies and B cells no longer being produced
Body’s ability to fight off infections is decreased, leading to AIDS
What does AIDS stand for
Acquired immune deficiency syndrome
