Chapter 5 - Invaders Flashcards
Antibiotic
Naturally produced or synthetic drug. Used to treat infections, that kills bacteria
Antibody
A protein produced by the immune system that detects, identifies and neutralises ‘non-self’ agents, such as bacteria and viruses; each antibody recognizes a specific antigen that is unique to its target; also called immunoglobulin’s
Antigen
An antigen is any substance that causes your immune system to produce antibodies against it. An antigen may be a foreign substance from the environment, such as chemicals, bacteria, viruses, or pollen. An antigen may also be formed inside the body, as with bacterial toxins or tissue cells.
Autoimmune disease
An autoimmune disease is a disease in which the body identifies some self cells as non-self cells and attacks them. (VCAA examiners report 2008). As a result the B and T lymphocytes attack and destroy self- cells as if they were invading pathogens. This kind of attack leads to a number of diseases such as Diabetes mellitus, Rheumatoid arthritis and Multiple sclerosis.
Bacteria
A member of a large group of unicellular microorganisms lacking organelles and an organized nucleus, including some that can cause disease.
Bacteriophage
A virus that invades a bacterium
Binary Fission
Division of a cell into two without mitosis, only in prokaryotes
Disease
Any condition that interferes without how an organism functions
Non - Infectious Disease
Non communicable diseases
Pathenogicity
The disease causing capacity of a pathogen. Not all pathogens cause disease all the time.
Virulence
Intensity of effect of disease
Incubation period
Period of which a host is infected but not displaying symptoms.
Disease Vectors
Disease transferring organisms
Eg.) Ticks, Flea, Mosquito, ect…
Viruses
Non- cellular
disease causing
Need host cell to survive and reproduce
antibiotics ineffective
DNA Vs RNA Vs Retrovirus
DNA: Double stranded DNA is injected by virus, DNA must be translated and transcripted.
RNA: RNA stand injected, and used to code for viral proteins.
Retrovirus: Inject RNA trand but have reverse transcriptase enzyme which transcribes RNA to DNA.
Virus replication
- Virus particle binds to plasma membrane of cell
- Viral DNA/RNA is injected and replicated
- Viruss are assembled within cell
- Cel lyse and virus’s are released
Viroids
Non - cellular
short peices of RNA
Prions
Non cellular infectious proteins
Do not contain genetic information
Prions exist naturally
When disease causing prions encounter normal prions it converts the normal prion into a disease causing prion.
effects neural tissue, brain function and co-ordination
How does bacteria cause disease
- Most bacteria is good
- But some bacteria can damage tissue as they grow and replicate as they produce powerful toxins as metabolic waste.
- large number of bacteria compete for healthy cells for nutrients and oxygen.
How bacteria spread
- Spread through direct contact, in food or water, or droplets of air.
Fungi and disease
Digestive enzymes of fungi break down organic material and absorb its nutrients.
Infectious vs contagious diseases
Strictly, a contagious disease is one transmitted by physical contact, whereas an infectious one is transmitted via microorganisms in the air or water. In practice, there is little or no difference in meaning between contagious and infectious when applied to disease or its spread.
Plant Physical barriers
- Waxy Cutile (smooth, water resistant)
- Hair on leaf (especially at stomata)
- Sunken Stoma
- Bark or thick layers of epidermis
Plant Chemical barriers
- Shed infected branches or leaves
- Secrete enzymes that destroy or deter pathogens
- Increase cellulose in cell wall to prevent penetration of physical invasion.
- Hypersensitive cell death
What is a pathogen
Infectious agent causing disease
