Lecture 11 - Immune System part 2 Flashcards
Virus
Not alive
Disease-causing agents
Do not undergo cell division
Inject DNA/RNA into a host cell
“hijacked cells” replicates virus
Virus Replication
1.Virus attaches to host receptor proteins
2. Genetic material is released into the host cell
3. Genetic material and proteins are replicated by
host cell “machinery” (enzymes, ribosomes)
4. Viral components assemble
5. Replicated viruses released from host cell
HIV Structure
Protease
Viral Envelope
Capside
RNA
Reverse Transcriptase
Attachment Protein
leads to aids
Replicates inside infected host cell
Infects and eventually kills all T helper cells
HIV replication
- Attachment protein
attaches to receptor molecule - Capsid released (RNA into cell)
- Reverse Transcriptase transcribes RNA to DNA (reverse transcription)
- Double stranded DNA
made and inserted into human DNA
Antibiotics
Chemicals
* Kills/inhibits microorganism growth
* NOT viruses
* Broad-spectrum
* Limited bacteria
* Prevent multiplication or kill
* Should not affect host/can do
Mutation causes ?
Mutation in Population causes antibiotic resistance
Vaccines
Active immunity - Natural-Self
Passive immunity – Artificial-Else where
B-cells for memory
Vaccines - Weakened
pathogen
Herd Immunity
A type of disease immunity that occurs when a large proportion of a population are vaccinated against a disease which prevents the spread of the disease to unvaccinated individuals.
Vaccine Graph
Initial - no antibodies
Primary R - small amount and takes time
Next - some left and memory B cells
Secondary - rapid responce producing a lot
Microbes which attack the immune system include what?
Viruses
Bacteria
Protozoa
Phagocytosis and production of immunoglobulins are two key functions of what type of cell?
Leukocytes
What pathogen is responsible for TB (Tuberculosis)?
Bacterium
Which theory states that when a B cell binds to an antigen it becomes selectively activated and proliferates rapidly?
Clonal selection theory
Which of these roles is the correct one for a T helper cell?
Release substances to activate B lymphocytes and T killer cells
Antibodies are released by which of the following?
Plasma cells
What word describes a microbe that causes disease?
Pathogen
What microbe causes HIV?
Virus
