Topic Test 1 + 2 - Microbes

4 types of viral shapes

Spherical, polyhedral, helical, complex

Yeast

yeast

• single cellular,

• Uses budding for reproduction

Moulds

• multicellular

• uses spores for reproduction

What do saprophytes do?

• they are fungi that release enzymes into surrounding cells, then breakdown food molecules and absorb enzymes.

Influenza - 3 types + 2 key differences between them

• A = antigenic shift + drift, 8 gene segments

• B = antigenic drift, 8 gene segments

• C = antigenic drift, 7 gene segments.

Role of H and N spikes + number of subtypes

H - responsble for latching or attaching onto the receptors on the cell. 18 subtypes

N - Neuraminidase releases the influenza virions from the host cell. 11 subtypes

Antigenic drift

• process that sees change within a virus, giving body’s immune system a harder time to fight against it.

Antigenic Shift

major change where whole segments of the genome are exchanged with a different flu virus in a process called genetic reassortment.

flagellates

• use flagella to move

ciliates

• use beating hairs to move

Psuedopods

• change in shape allows movement

Prions

Normal prions have a set 3d shape

• when an abnormal prions comes into contact with a prion it causes it to alter shape and stops normal function

parasites - Primary stage/host

• adult phase

• where reproduction occurs

Parasites - Secondary host

• Larvae stage

• Asexual reprodution occurs (only one parent cell needed)

Genome

• contains the genetic code

Phosphylate envelope

Mediates interception between virus and cell receptors

Capsid

• engulfes RNA/DNA as protection

Endocytosis (attachment)

• spikes from virus attach to receptors on surface of host cell

• Virus then fuses with cell membrane and viral contents are released into the cytoplasm

Exocytosis (release)

occurs when a vesicle fuses with the plasma membrane, allowing its contents to be released outside the cell

infectious disease

• Disease caused by infections organism or agent

Zoonotic

• animal diseases that can be transmitted to humans

Miasma theory

• disease is caused by ‘bad air’ called miasmas

• and air vapour that is polluted

Germ Theory

• disease can be caused by microorganisms entering the body

Koch 4 pastulates

1. Must be found in a diseased person

2. must be then cultured from diseased culture

3. then recaptulated to a healthy host

4. Then matched to the original disease

R - naught

this measures the contagiousness

• amount of people one infected person can expect to transmit the disease

Pathogen

• a disease causing agent

• must avoid hosts immune system long enough to infect another host

Incubation V infection period

Incubation period is time from infection until symptoms occur

Infectious period is time in which disease can be spread

Carrior V vector

• A carrior is an Asymptamatic host, that can transmit the disease

• Vector - creature that carries disease from one host to another

Signs V symptoms

signs - change of a disease that can be measured or observed

symptoms - characteristics only described by patient of disease

Prevelance

• total cases in population

Incidence

• Measures # of new cases over time

Mortality rate

number of deaths/ total population

Endemic / epidemic / pandemic

• Endemic disease that is always present in population

• Epidemic - sudden, localised outbreak of disease within population

• Pandemic - Global spread of disease over multiple continents/countries