summerqswrong Flashcards
my do people sometimes lose immunity
- memory cells have a limited life span
- if no repeat infections occur then there is no further exposure
- no secondary response occurs if there is no exposure
why is it not possible to produce an effective vaccination for malaria
- many different forms of plasmodium due to mutation/ variation
- different strains require different vaccines
- plasmodium cant be detected as it hides in RBCs and liver cells
- more than one stage in the lifecycle so will need a different vaccine for each stage
what does the constant region act as
a marker for phagocytes
talk abt how the ultrastructure of a neutrophil is specialised
- has a well developed cytoskeleton
- many mitochondria to provide energy for movement
- many lysozymes that break down the engulfed pathogen
- many ribosomes ((for protein synthesis))
- lots of glogi
- many receptor sites on PM
what infective agent causes AIDS
HIV
how do needle exchange programmes reduce transmission
- used needles are contaminated, this programme reduces the chance of sharing needles
- exchange of bodily fluids
how are viruses ( containing RNA) able to take control of host cells
- (the reverse transcriptase is in host nucleus)
- the viral DNA is inserted in host chromosome/DNA.
- viral RNA is produced and transcribed
- this codes for viral proteins
factors increasing the chance of infection with TB
- poor ventilation
- homelessness
- no vaccination (difficulty accessing vaccination)
- weakened immune system
- close contact with someone with TB
describe how a cytokine molecule can stimulate a B cell to divide
- cytokine receptor has a specific shape
- cytokine attaches to receptor (on cell surface of B cell)
- receptor and cytokine have complimentary shapes
- this activates clonal expansion/ mitosis
whats a parasite
an organism that lives on/ in a host and it makes the host ill by taking its nutrients
what are groups of people considered vulnerable
- pregnant woman
- babies
- those with weakened immune systems
- health workers
- the elderly
- young people
describe the role of memory cells when influenza enters the body
- they are responsible for the secondary response and can change to form t cells (or b cells)
- clonal expansion occurs
- plasma cells can release antibodies complimentary to influenza
with tfl the host cell membrane cant be broken down, explain how this will reduce the spread of a virus such as influenza
- the virus wont be able to leave the cell so cannot spread to other cells
- fewer viruses are produced so fewer viruses when sneezing and coughing.
two features of the malarial parasite showing its not a prokaryote
- nucleus
- Golgi apparatus
