what is host specific mean (virus) | refers to the specific cell viruses must occupy and use to replicate due to the specific viral receptors on the host cell surface. required for the virus to attach to the cell. |
what are the qualities of COMMUNICABLE DISEASE | -(infectious/transmissible)
-Caused by foreign organisms invading the body and multiplying
-contagious
-passed by contact or vector (intermediate host, eg mosquito)*
-pathogens * |
Pathogens? | Disease causing organisms
most common= bacteria and virus
can include fungi and parasites |
What are the qualities/qualifications of BACTERIA | -Most are non pathogenic
-eg. decomposition, human digestion
-Microscopic single celled organisms
-Rapid multiplication can kill cells
-Can secrete toxins
-Classified by cell shape
-can contain both DNA and RNA |
cocci | spherical cells - bacteria |
Bacilli | Cells with flagella - bacteria |
Spirilla | Twisted cells- bacteria |
Vibrio | Curved rods, comma like cells- Bacteria |
Label Bacteria | . |
What is the role of vectors and common vector borne diseases | Vectors are frequently arthropods, such as mosquitoes, ticks, flies, fleas and lice.
carry pathogens that can multiply within their bodies and be delivered to new hosts, usually by biting.
-Malaria (mosquitos)
-yellow fever
-Lyme disease (ticks) |
Label virus and describe structure | glycoprotein spike -petruding
protein envelope -on surface
RNA or DNA internal
nucleocapsid -nucleic acid + protective capital internal
membrane protein-external. |
pathogenic organisms & examples | Bacteria- ghoneria, clamidia, syphillus, phnumonia
Animal Parasites- lice, tape worms, malaria
virus - covid, ross river,
fungi - |
What are the qualities/qualifications of Viruses | Contain DNA or RNA surrounded by capsid(protein coat)
^ Induces host to manufacture more virus particles (CANNOT REPRODUCE ALONE)
most insert genetic material or enter cell through endocytosis |
Bacteriophanges | Virus using bacteria as host |
cell lycing | the breakage of cell membrane due to over replication of virus within |
Transmission modes of pathogens | Contact
body fluids
airborne transmission
ingestion
droplets
vectors |
Non specific defences overview | innate immune system
works against ALL pathogens
first line of defence |
Types of non specific defence -EXTERNAL | skin -oil sebum barrier, sweat
Mucous membranes - line cavities, mucous inhibit entry
lysosomes-enzyme that kill bacteria, eyes
Acids eg stomach, vag, sweat
hair + cilia
cerumen -wax
flushing action urine, anal |
Specific defences overview | Adaptive/ acquired immune system
directed at particular pathogens
ie antibodies formed after illness |
Phagocytes +two examples | Cells that can engulf and digest(destroy) micro organisms/ eliminate pathogens
eg. leucocytes (white bc) & microphages |
Inflammatory response purpose | reduce -pathogen spread, destroy them, prevent entry
Remove - damaged tissue/ cell debris
Repair- damaged tissues |
Signs of inflammatory response | Red, Heat, Swelling, Pain |
Endocytosis | Endocytosis is a general term describing a process by which cells absorb external material by engulfing it with the cell membrane - occurs with virus such as influenza |
Lysogenic cycle (HIV multiplication method) | the virus bind to a cells receptors inserts its DNA into the cell, allowing the virus RNA to be copied and passed on along with the cell's own DNA producing new viral RNA, to be release to infect other cells
- eg HIV multiplication using lymphocytes |
Lytic cycle ( Influenza multiplication method) | the virus introduces its genome into a host cell and initiates replication by hijacking the host's cellular machinery to make new copies of the virus. continue until cell bursts (cellular lysis) |
Cell lysis | breakage of cellular membrane due to rapid viral multiplication overfilling cytoplasm + increasing pressure. killing of cells/ disruption to regular activity causes symptoms of illness |
Binary fission | reproduction method where organisms double in material then split in two - used by bacteria |
What is plan C | how antibodies work
precipitation
lysis
agglutinin
neutralisation
coat |
Antibody step: precipitation | tbc |
Antibody step: lysis | tbc |
Antibody step: agglutination | agglutination |
Antibody step: neutralisation | tbc |
Coat | tbc |
HIV Endocytocis process | . |
what is host specific mean (virus) | refers to the specific cell viruses must occupy and use to replicate due to the specific viral receptors on the host cell surface. required for the virus to attach to the cell. |
describe phagocytosis. what white blood cell is actively engaged in it | the ingestion of bacteria, dead cell materials or particles by cells
it is the major function of macrophages
the pathogen interacts with phagocyte receptors
phagocyte envelops pathogen and activates lysozyme
pathogen is digested and broken down into proteins
complex formed including pathogen DNA to form a major histocompatability complex (MHC) -antigen (adaptive immunity |