B5 Communicable Diseases Flashcards
What is measles?
Measles is a viral disease spread through droplets
What are the symptoms of measles?
Symptoms:
- High Fever
- Severe Red Rashes
- Blindness
How do you prevent measles?
You can avoid the spread of measles by:
- Wearing masks
- Having good ventilation in a room
- Taking the vaccine
What are communicable diseases?
Diseases that can be spread from one organism to another
What are the four types of pathogens?
- Bacteria
- Viruses
- Fungi
- Protists
How do bacteria cause illness?
Bacteria reproduce asexually by binary fission. They produce large number of bacteria very rapidly then they release toxic substances called ‘Toxins’ to damage the cells in your body.
What is binary fission?
The asexual reproduction by a separation of the body into TWO new bodies.
Two examples of a bacterial disease?
Salmonella
Gonorrheoa
Symptoms of Salmonella :
-Diarrhoea
-Fever
-Vomiting
-Severe stomach cramps
How does salmonella transmitt and how can it be reduces?
Transmitted by partially cooked meat
Transmissions can be reduced by good hygine, vaccination and cooking meat thoroughly
Symptoms of Gonorrhoea:
- Pain when urinating
- Yellow or green secreation from vagina and penis
How is gonorrhoe transmitted and how to treat it?
Transmitted throught sexual intercource so barrier methids are advised
Antibiotics are used to treat it
Are viruses as living organisms?
No,as they don’t fit the all 7 living characteristics (MRSGREN)
How do viruses infect?
Viruses inject their genetic materials into host cells and replicate inside the host cell. Eventually the host cell bursts as there is not enough space for new viruses
Give three example of a viral disease?
Measles
HIV (Human Immuno-defiency Virus)
TMV (Tobacco Mosaic Virus)
How is Human Immuno-Deficency Virus (HIV) transmitted?
Transmitted through mixing of body fluid such as blood,semen or sharing needles
What happens when someone is infected with HIV
They don’t instantly show sypmtoms, but once the virus is triggered they start to reproduce and damage white blood cells making the person more susceptible for other infections
Symptoms of TMV:
Mosaic patterns in leaves
Stunted growth
How is growth stunted with TMV?
There won’t be enough cholophyll to absorb sunlight for photosynthesis
This means there is not enough glucose produced for respiration to relase energy
It also means that there is not enough glucose to make amino acids and protiens for growth and repair
How is TMV transmitted?
Through roots and wind
What are fungi?
Eukariotic cells which can either be unicelluar or multicellular
How do fungal disease transmitt?
Throught direct physical contact
They have thin,branched and filoment like structure called hyphae and they can penetrate through the skin in animals and bark in trees.
An example of a fungal disease?
Rose black spots (plants)
What are the symptoms of rose black spots?
Stunted growth
Black spots in leaves
How do rose black spots spread?
Wind carrying spores
Direct/physical contact
How to reduce the transmission of Rose black spots?
Anti-fungal sprays
Removing infected plants
What are protsists
Single-Celled Eukaryotes
Why are mosquitos vectors?
As they transfer malaria from one person to another
What are the symptoms of malaria?
Episodes of a fever
How to prevent malaria?
Anti-repellant
Kill mosquitos
Leave not water sources (breading sites)
What is immuntiy?
The ability of your body to fight against pathogens
What does the first line of defence consist of?
- Goblet cells in trachea produce mucus to trap pathogens
- HCL in stomach
- Lysozyme enzyme in tears and saliva
- Nasal hair
- Blood-Clots
What is the second line of defence?
Phagocytes
What is the process of phagocytosis/engulfing?
They ENGULF (not eat) a pathogen and release digestive enzymes to kill the pathogen, eventually the products of digestion are absorbed
What is the third line of defence?
Lymphocytes
How do lymphocytes work?
Lymphocytes with complementary recpetors are stimulated and start to divide by mitosis cell division (to make a clone of cells)
Some cells secreate antibodies (to kill the pathogen directly or to make it eaiser form phagocytes to engulf the pathogen)
Some cells are stored as memory cells incase pathogen returns
How can pathogens spread?
- Water
- Air
- Direct contact
What has made it harder to treat gonorrhoea?
Bacteria have become resitant to the antibiotic penicillin which is used to treat gonorrhoea
Suggest why it’s important to wash your hands thoroughly before cooking?
To prevent contamination of food
How could you detect that a plant has a disease?
1) stunted growth
2) spots on leaves
3) areas of decay (rot)
4) malformed stems or leaves
5) discolouration (of leaves)
6) the presence of pests.
Physical defences of plants :
- Cellulose cell walls.
- Tough waxy cuticle on leaves.
- Layers of dead cells around stems (bark on trees) which fall off.
Chemical defecenes of plants:
- Antibacterial chemicals.
Poisons to deter herbivores
Mechanical defences of a plant:
- Thorns and hairs deter animals.
- Leaves which droop or curl when touched.
- Mimicry to trick animals.
Explain how a NITROGEN ion deficiency could affect a plant.
Nitrogen is needed for plants to make protien so a lack of nitrogen leads to stunted growth
Explain how a MAGNESIUM ion deficiency could affect a plant.
Magnesium is needed for making chlorophyll
No chlorophyll — No glucose — No respiration — No protien-synthesis = Stunted growth
