Module 4.1 Flashcards
name of disease 1
tuberculosis
type of pathogen of disease 1
bacteria
transmission of disease 1
droplets / airborne (sneezing )
symptoms of disease 1
tiredness , night sweats , lack of appetite
organisms affected by disease 1
humans
Prevention / treatment of disease 1
vaccination - prevention
treatment - antibiotics
name of disease 2
athlete’s foot / tinea pedis
type of pathogen in disease 2
bacteria
transmission of disease 2
contaminated towels / clothes and surfaces
symptoms of disease 2
itchy red rash between toes
organisms affected by disease 2
humans .
prevention/ treatment of disease 2
antifungal medication
name of disease 3
bacterial meningitis
type of pathogen of disease 3
bacteria or virus
transmission of disease 3
droplets from coughing sneezing etc
symptoms of disease 3
babies - high fever , drowsiness
older children - seizures , muscle pain
organisms affected by disease 3
humans
prevention / treatment of disease 3
intravenous anitbitoics
name of disease 4
potato / tomato blight
type of pathogen in disease 4
proctoctist (protist)
transmission of disease 3
direct contact with watery rot on the surface .
symptoms of disease 4
tomato - leaves and stems , brown patches may appear on stem .
-fruit may decay more rapidly . Same for potatoes .
organisms affected by disease 4
tomatoes and potato
prevention / treatment of disease 4
growing more tomato’s and potato’s in a greenhouse .
name of disease 5
HIV
type of pathogen in disease 5
virus
transmission of disease 5
unprotected sex , sharing blood
symptoms of disease 5
fever , rash , muscle and joint pain
organism affected by disease 5
humans
prevention / treatment of disease 5
treatment is antiretroviral drugs
prevention is to use condoms
name of disease 6
black sigatoka
type of pathogen in disease 6
fungus
transmission of disease 6
rain splash , wind during wet conditions .
symptoms of disease 6
mottling , yellowing of tissues , poor yield
organisms affected by disease 6
plants
prevention / treatment of disease 6
destruction of infected individual
name of disease 7
ring rot
TYPE OF PAthogen in disease 7
bacterium
transmission of disease 7
direct contact with infected tubers
symptoms of disease 7
skin of the potato may crack and ooze can emerge from the heel end and soil
organisms affected by disease 7
potato
prevention / treatment of disease 7
prevention is use seeds that are pathogen free .
-there is no treatment
name of disease 8
malaria
type of pathogen in disease 8
parasite -
Plasmodium falciparum
transmission of disease 8
mosquito
symptoms of disease 8
vomiting , diarrhoea , sweats and chills
organisms affected by disease 8
humans
prevention / treatment of disease 8
wearing bug repellent spray and sleeping inside a mosquito net /
name of disease 9
tobacco mosaic virus
type of pathogen disease 9
virus
transmission of disease 9
infected leaves rub against healthy plant
symptoms of disease 9
defective fruit
organisms affected by disease 9
plants
prevention / treatment of disease 9
application of fungicide , removal of affect leaves .
name of disease 10
ring worm
type of pathogen of disease 10
fungus
transmission of disease 10
human- human contact
human- animal contact
-human - object contact
(rare ) = human - soil contact
symptoms of disease 10
silvery , red ring- like rash on skin
organisms affected by disease 10
humans
prevention / treatment of disease 10
antifungal drugs
-keep area dry
name of disease 11
influenza
type of pathogen disease 11
virus
transmission of disease 11
airborne (coughs and sneezes )
Symptoms of disease 11
high temperature , 38 above , tiredness , weakness and headaches .
organisms affected by disease 11
huamans
prevention / treatment of disease 11
bed rest
One way of transmission
direct contact
-direct physical contact , such as touching a person who is infected or touching contaminated surfaces (including soil ) that harbour the pathogens . (HIV , bacterial meningits ring worm and athlete’s foot . )
ways to prevent direct contact transmission
hygiene ; washing hands regularly - especially after using the restroom .
keeping surfaces clean - especially door handles.
-cleaning and disinfecting cuts and abrasions .
-sterilising surgical instruments .
-using condoms during sexual intercourse .
faecal-oral
usually by eating food or drinking water contaminated by the pathogen .
-for example ; cholera , food poisoning .
ways to prevent faecal oral transmission
using human sewage to fertilise crops is a common practice in some parts of the world .
-treatment of waste water and treatment of drinking water are important ways to reduce the risk .
-thorough washing of all fresh food (using treated water ) .
-careful preparation and thorough cooking of all food .
third way of transmission
droplets
-droplets infection , in which the pathogen is carried in tiny water droplets in the air
for example tuberculosis , influenzas and covid
ways to prevent droplet transmission
catch it , bin it and kill it .
-cover your mouth when coughing or sneezing . Use a tissue and ensure the tissue is disposed correctly .
-face masks .
fourth way of transmission
spores
transmission by spores which are resistant stage of the pathogens , these can be carried in the air or reside on surfaces or in the soil .
(example anthrax and tetanus )
ways to prevent spores transmission
use of a mask
washing the skin after contact with the soil
indirect - malaria
a vector is another organism that maybe used by the pathogen to gain entry to the primary host .
(e.g malaria caused by plasmodium parasite enters the human host via a bite by the female mosquito )
transmission of plant pathogens
–pathogens prevent in the soil can enter the plants via roots .
-fungi produce spores that can be airborne .
-infected leaves shed and carry pathogens back into the soil .
-pathogens can enter fruit and seeds , infecting offspring .
-infects can indirectly plants and vectors .
the effect of climate
many proctitis bacteria and fungi can grow and reproduce rapidly in warm and moist conditions .
-Therefore ,they , tend to be more common in warmer climates
in cooler climates
-these pathogens maybe damaged or even killed by cold winter weather 0 such weather will certainly reduce the ability to grow and reproduce .
-as a result there is a greater variety of diseases to be found in warmer climates , and animas or plants living in these regions are more likely to become infected .
Communicable diseases
can be spread between organisms either of the same sspecies , or sometimes between different species .
-communicabe diseases spread by pathogens ,
-pathogens are micorgansims that cause disease .
host –> organisms are what pathogens infects .
bacteria (2)bacteria (2)
also , bacteria do not have other membrane bound organelels like motochondira .
-bactceira are also surroudned by a cell wall containing the chemical petidogylcen .
how bacteria enter the cell
-once they ener the body , pathogenic bacteri can release toxins .
-Toxins are chemcials which damage the host cells and tissues leding to be symp whattt
-another way bacteria can enter host cells
-some bacteria can enter host cells and prevent them from functioning normally - e.g bacteira that cause tuberuclosis are much smaller than baceria .
-difference between bacteira and virus
-unlike bacteria , virusses are non-living no cells trucutre at all .
-viruses consits of genetic mterials can be dna / rna .
-the genetic material is wrapped around a protein strucutre called a capsid .
viruses also attach what ?
viruses also have attachment proteins , which allow the virus to attach virus to attach to hsot cell .
-some viruses also contain a lipid envelop e.
Key feature ; virsues ,,c annot reporduce outside of a hsot cell –? to reproduce a virus attaches to the host cell and hen passes thorugh the cell meembrna
how do viruses work with the hos cel .
virus then copies itsel using the enzyme of the host cel .
-the virus particles now leave the host cell and gd go on infect new host cells and continue reporducing .
-virus prevents the hsot cells from functioning normally . In many cases , virus can lead to the death of the host cell .
Fungi
-are eukryotic organismd .
-they can be unicellular or multiceullar .
FUNGI : obtain their bnutrients by releaasing enzymes and digresting the matrrial around htem .
the products of digestion are then absorbed BACK INTO THE fungal cell .
-Tjis process of digestion can cause damage to hot cells and tissues .
-when they reproduce , fungi release a large amount of spores .
-so fungal diseses can spread very wideluy .
-Many species of fungi are found on the remiansresad very widey .
-Many species of fungi are found on the remains of dead organsisms , where hey ake part in the decay proces .
However , pahogenic fungi are found on lviing organssms where hehy cuse disease .
-e.g in humans fungi causes thrush and athlete’s foot .
-fungi can cuase a range of disease in plans . incluing some which re very destructive .
-by dmging the leaves , fungi can reduce the rate of photosynthesis . severyly reducign the yield of plant crops .
protoctista (protista) –> eukaryotic organsimss .
-these protoctista act as pathogenic parasites in humans .
-ciarda cises doarrpea ad si transmited when humans dink water coaining infexrws water .
-plasmodium is the pthogen that causes malria in huans and is transmitted between uhmans by mosquitoes .
human body has a number of ways to protect itself from infection bbyoathgoens .
-number one specific immune sytem –? respone of he specific immune system is tailored to each pathogen .
-w-when the specific immune sytem fights off aprticular pathogen , it then becomes more effective at fighting off a second infection , by the same pathogen .
–body has w hole rnge of non-specific diefences precent pthogens from gainign acess to the body .
-unlie tthe specific , the no-speciifc defence is the same for all pathogens .
1.line of defence is the skin
Which provides a protective layer for the majority of body surfaces .
SKIN —> has many layers of cdlls , including a layer of desd cells. This makes the skin difficult for pathogens to penetrate .
What is the surface of the skin covered with
It is covered with an oily denim produces by sebaceous glands .
-this forms a slightly acidic layer , which can prevent thee growth of harmful bacteria .
-healthy skin is also
Covered worj harness
Micrograjosms which reduces fhe growth of pathogens by competing for resources .
However , pathogens CAN enter the body via openings e.g breathing and digestive system .
These are lined with a protective layer called mucus membrane .
-SHEIN for the trachea in the breathing Sheen .
-l
What do mucus membranes do
Mucus membranes , secrete mucus which trap
Microorganisms .
-these microorganisms can be destroyed by white blood cells got phagocyte.
-mucus also contains the enzyme
Lysosome which destroys bacteria by digesting the bacteria cell wall .
Where else is lysozyme also found in?
Lysozyme is also found in tears .
Helps to prevent pathogens from entering via the eye .
In the stomach , mucus contains hydrochloric acid .
-hcl helps to kill any pathogens in food :water .
Sometimes , pathogens can made the body through openings such as the mouth or nose .
-in this case , the body tries to expel the pathogen .
-These are Ken as expulsion refluxes .
-these include sneezing , coughing , vomiting and diarrhoea .
-Anotjer way pathogens can enter , is the skin is damaged e.g a cut
-in this case , the body responds by trying to seal the damaged area .
Before , a large number of pathogens can enter aka blood
WHWRE
Blood clotting invovles platelets which are found in the blood stream
Platelets - tiny - short lived fragments of cells with no nucleus .
-platelets are formed y continuing in the bomearrow before being released into
The blood .
The scab protects , the underlying tissue from
Pathogens while wound healing takes place .
Skin cues , under the scab divide and repair the samamage ,
Eventually , scab falls off and freshly repaired skin continues its
Job from
Protecting the body from
Pathogen entry .
Tissue damages can also result in inflammation .
-this is when the tissue is damaged and activates most cells .
-when most cells are activated , they release a chemicals
Called jsofkme
.
-histamine has multiple effects .
Histamine effect in je
Histamine causes something blood vessels go dilate or widen .
-scientists cal fhis vasodilation .
-this increase the supply of blood to the effected area /
-causes the area to feel
Appear red
-increased temperature reduce pathogenic ability to reproduce .
Second effect of histamine
-blood vessels walla , are more
Permeable .
-histamine allows
More blood
Plasmas tk
Leave and fork tissue fluid .
The effect of this is to cause nearby tissues to swell and feel
Painful .
Scientist cal tjis sweeping oedma.
As well as histamine , most cells also release chemicals called cytokines
Cytokines wee a whole range of chemicals produced by the body .
-ok fhe respond to an intense
Cytokines attract phagocytosis’s to the damaged area in order to caddy out phagocytosis of any pathogen and prevent it from.
Some cytokines can reveal to the hypothalamus in the brown where they trigger an increase in body temperature
This increase in body temperature reduced the pathogens ability to reduce .
Picture shown of small arteriole
Walls of the blood besssl have a layer of cells called the endothelium .
Just outside the endothelium there are smootj
Muscle
Cells and proteins such as collagen
-of the endothelium
Is
Damaged sxmplas the skin is cut ,
What would happen .
Then the platelets are
Exposed to the
Proteins outside the endothelium
.
This activates the plates which now trigger blood
Clotting .
-blood clotting is complexed
So only
Noeed
Do know
Somploef beesion.
-when activated , platelets form a plug over the damaged area .
-the platelets also release cjemcoals called clogging factors including
Thromboplastin
Thromboplastim , together with calcium
Ions on the blood , now act in a blood protein called prothrombin .
-this concerts the prothrombin into an active enzyme called thrombin .
Thrombin now acts in a soluble blood
Protein called fibrinogen .
Catalysing the formation
Of ineoldune for mom
.
The insoluble fibrin forms
W
Mesh , with traps res blood cells forming a blood clot
Or thrombus .
-as well as triggering a blood clot , the actives platelets Wlso
Release a chemical called serotonin.
Seretomim causes the smooth muscle cells in the blood vessel walls to contact .
This narrows the blood besses reducing the blood
Flow
To
The damaged area .
-body can now start to repair the damaged blood vessels .
Blood clot also
Prevents energy of pajtiehjs , overtime clot dries to form a scab on the surface of the skin
…
Key ; as well as red blood cells , the blood aso has white blood cells .
-there are two categroies of white blood cells what is the first one ?
-first , catgeort is phagocytes .
-however , macrophagesges also play a role in the specific immune sytem .
we also have neutrophills .
The secondary category is lymphocytes
There are two types of lymphocytes
B lymphocytes and t Limpopo it’s
Lymphocytes form the specific immune syfem
Shown a bacterial cell
KEY: surface of pathogens —> bacteria are covered with chemiCals fhag are not found in humans .
-usuallg , in the case do bacteria fhe chemicals are often part of the bacterial cell wall .
What does the bloood contain fhags super sick
Blood contains special molecules which can recognise these foreign chemicals and Stirck to them .
-scientists call these molecules opsonis