half-term 4 Flashcards
what is the simple definition of a virus?
a package of genetic material wrapped in a protein coat
what are the 7 characteristics of life?
movement respiration sensitivity nutrition excretion reproduction growth
what are 2 type of viruses that affect animals?
aden oviruses and coronaviruses
what type of virus infect bacteria?
bacteriophages
which coronavirus caused COVID-19?
SARS-CoV-2
explain the reason for washing you hands with soap to help prevent the transmission of COVID-19
this genetic material is packaged inside a lipid envelope which can be broken apart by chemicals in soap. once broken up the virus is harmless and can no longer be caught or transmitted
how can fungi reproduce
both sexually and asexually
example of a single-celled fungi
yeasts
what do fungi’s cell walls contain
chitin
what is hyphae
branching filaments
what is the reproductive part of fungi called
the fruiting body
how do fungi obtain food
fungi use their hyphae, which elongate & branch off spreading the mycelium through soil or through living or dead plant or in animal tissues.
what are decomposers?
fungi obtain their food substances from dead organic matter, break down & get rid of dead organisms
what are Lichens?
an association of a fungus, & a plant that photosynthesises.
what is one example of a useful use of bacteria
making yogurt
how is anthrax spread
inhaled
how is whooping cough spread
spread through the air from person to person
how is Lyme disease spread
spread by ticks
how is chlamydia spread
sexually transmitted
how is botulism spread
develops if a persons ingests the toxin
how is tetanus spread
from soil and manure it can enter through a break in the skin
how is diphtheria spread
spreads through droplets
how is diarrhea spread
droplet infection
how is meningitis spread
coughing, sneezing, kissing
how is stomach ulcers spread
person to person in close contact
how is legionnaire’s disease spread
by inhaling droplets of water
how is listeriosis spread
transmitted via the oral route after ingestion of contaminated food products
how is leprosy spread
coughing or sneezing, droplets
how is tuberculosis spread
spreads through the air
how is gonorrhoea spread
sexually transmitted
how is salmonellosis spread
contaminated food and drink
how is pneumonia spread
pathogen entering the lungs
how is cholera spread
food or drink contaminated with infected persons face.
what are protoctists or protists?
single-celled organisms that are not anima, plant or fungi
what are the two things all proctists/protists have in common?
they are all very simple and small.
3 protocists that live in fresh water
Amoeba, Paramecium and Euglena
information about Amoeba
move by bulging their cytoplasm, to slide across a surface
information about Paramecium
slipper shaped organism with many hair like cilia around the outside of their membrane
information about Euglena
have characteristics of both animals (have a long flagellum and move, have an eyespot and move towards the light) and plants (have chloroplast and photosynthesise, they store starch
what do Parasitic protoctists include?
Plasmodium
the life cycle of plasmodium vivax (7)
1 human- female mosquito bites the human
2 human- the malaria parasite, Plasmodium, travels in the blood
3 human- the malaria parasite infects the liver
4 human- the malaria parasite reproduces asexually
5 the mosquito consumes infected blood when feeding
6 mosquito- the malaria parasite travels from the gut to its salivary glands
7 mosquito- the malaria parasite reproduces sexually
6 of the body’s primary defences and explanation of how each one performs
- tears (contain an enzyme that kills some microbes)
- mucus (traps particles and contains an enzyme that kills some microbes)
- cilia (there are fine hairs in the airways. move trapped microbes back up out of the body)
- skin (stops microbes from entering the body)
- scab (blood clots over a wound to prevent microbes from entering the body)
- stomach acid (kills many microbes)
after the body’s primary defences what is the next line of defence?
white blood cells
what are the three types of white blood cell and what do they do?
- Phagocytes- ingest microbes and destroy them
- ‘B-cells’- produce antibodies
- ‘T-cells’- produce antitoxins
what happens when microbes infect the body?
white blood cells numbers increase and blood flows to the site of the infection.
white blood cells
cells in the blood that help fight disease, for example by producing antibodies
immune system
the parts of our bodies that fight disease caused by pathogens such as viruses and bacteria, including the white blood cells
phagocyte
a type of white blood cell that ingests and digests harmful particles such as bacteria
antibody
a molecule made by the immune system that recognises microbes and helps get rid of them
memory cell
a white blood cell that makes antibodies to fight infection caused by pathogen; it can quickly fight the same pathogen if it should enter the body again
what happens once an infection is overcome?
- Once an infection is overcome, the number of white blood cells returns to normal levels.
- However, some T cells and B cells remain as memory cells.
- If the same pathogen infects the body again, these memory cells react quickly
- This is why we don’t often suffer from the same disease twice: we are now immune to it.
how does mutating affect what happens after you overcome the flu?
- Some pathogens, such as those that cause flu, can mutate
- This means there are small changes in their DNA which means they produce slightly
- different proteins (antigens).
- This means that the memory cells do not recognise them so we can get flu each year.
