Biology 2 - Infection And Response Flashcards
‘A breakdown in the cellular control mechanism that limits cell division’ - what is this the definition for
Cancer
Cancer - cells that ? be stable begin to ? forming a tumour that divides continuously
should, divide
What happens with a benign tumour?
There is a growth of abnormal cells - usually contained in one area and can grow very large
What is a good thing about a benign tumour
They don’t destroy surrounding tissue or invade other parts of the body
Benign ? can ? tissues preventing normal ? flow or nerve function
tumours, compress, blood
What can a malignant tumour cause
Cancer
Malignant tumours ? surrounding tissue and their ? can break ? and spread through ? or lymph into other sites where they ? secondary ?, malignant ? invade surrounding ? and ? normal cells
destroy, cells, away, blood, form, tumours , tumours , tissues, kill
What are the two types of treatment for cancer
Radiotherapy and chemotherapy
What two things does chemotherapy do
use chemicals to stop cancer cells dividing or cause them to self destruct
What does radiotherapy use and do to treat cancer
using targeted doses of radiation, cancer cells are destroyed - this stops cancer cells dividing
3 noticeable signs meaning there could be plant disease
Spots on leaves, stunted growth, discoloration
What are the symptoms of an aphid (green fly) infestation
Mottled or yellow leaves, decreased growth rate, wilting, low yield and death
Problems with aphid (green fly) infestation :
-Feed on ? sap, reducing the turgar ?, so the plant ?
-Release a ? honey dew that encourages ? growth
-Any pathogens in the ? of the aphid is injected into the ?
-Holes left from ? feeding can allow secondary ? in
-Honeydew encourages ants and other ? into the ?
-phloem, pressure, wilts
-sticky, mould
-saliva, plant
-aphid, protists/pathogens
-animals, plant
What non pesticide control can be used to control aphid infestation (2 examples)
-Squash aphid colonies
-Encourage natural aphid predators, eg: ladybugs
What pesticide control can be used for aphid infestation?
Insecticide
What can magnesium deficiency cause in plants
discoloration of leaves (yellow leaves) and stunted growth
what can nitrate deficiency cause and why?
stunted growth, because nitrate is needed to make amino acids which is used in photosynthesis to help the plant grow. Nitrates then help make hydrogen which helps makes amino acids and therefore proteins which is needed for healthy growth!
what does lack of chlorophyll being made due to a magnesium deficiency cause
the leaves turn yellow because of the lack of chlorophyll and because of that less photosynthesis takes place so less glucose made, less amino acids and less protein for growth leading to stunted growth
3 ways to identify what disease a plant has
- reference to a Garden manual or website
- taking the infected plant to a lab to identify the pathogen present
- using testing kits containing monoclonal antibodies
Physical plant defence mechanisms:
Cellulose cell walls
Tough waxy cuticle
Layers of dead cells around stem (eg bark) which fall off
Chemical plant defence mechanisms
Poisons to deter herbivores
Antibacterial chemicals
Mechanical adaptations for plant defence
Leaves which droop of curl when touched
Thorns and hair to deter animals
Mimicry to trick animals
how many lines of defence are there against diseases?
3
what does the first line of defence do and is it specific or non specific?
prevent pathogens from entering the body, non specific