B5- Communicable diseases Flashcards
3 factors that affect health
Diet
Stress
Lifestyle situations e.g where you live
Communicable disease definition
A disease that can be passed from one person to another
Non-communicable disease definition
A disease that cannot be passed from one person to another
Pathogen definition and examples
Microorganisms that can cause disease
Bacteria, fungi, virus
Bacteria
Type of cell?
How do replicate?
Why are they bad?
Size compared to viruses?
Prokaryotic
Binary fission, splitting in two
Produce toxins that cause damage to tissue and cause symptoms
Bigger
Viruses
Type of cell?
How do replicate?
Why are they bad?
Size compared to bacteria?
Not a cell
Use host’s DNA inside of cell
Damages the hosts cell
Smaller
3 ways disease spread and examples of how they spread in humans
Air- coughing, sneezing, breathing in droplets
Water- drinking dirty water, uncooked food
Contact- skin and sexual contact, dirty needles
3 ways disease spread and examples of how they spread in plants
Air- fungal spores by the wind
Water- fungal spores carried by splashes of water
Contact- small piece of infected plant can infect field of crops by soil
2 bacterial diseases
Gonorrhoea, salmonella
3 viral diseases
Measles, HIV, Tobacco mosaic virus
1 Fungal disease
Rose black spot
1 Protist disease
Malaria
Measles
Type of disease?
Spread?
Symptoms?
Management?
Virus
Inhalation of droplets, sneezes and coughs
Fever, red rash
Vaccinate children
HIV/AIDS
Type of disease?
Spread?
Symptoms?
Management?
Virus
Sexual contact, bodily fluids
Flu like disease, attacks immune cells
Antiretroviral drugs
Tobacco Mosaic Virus
Type of disease?
Spread?
Symptoms?
Management?
Virus
Direct contact
Mosaic pattern of discolouration on leaves
Remove infected plants
Salmonella
Type of disease?
Spread?
Symptoms?
Management?
Bacteria
Uncooked food, unhygienic conditions
Fever, abdominal cramps, vomiting
Poultry vaccinated
Gonorrhoea
Type of disease?
Spread?
Symptoms?
Management?
Bacteria
Sexual contact
Yellow/green discharge from sexual organs
Antibiotics
Rose Black Spot
Type of disease?
Spread?
Symptoms?
Management?
Fungus
Water or wind
Black spot on leaves, turn yellow and drop
Fungicides
Malaria
Type of disease?
Spread?
Symptoms?
Management?
Protist
Female mosquito bites
Recurrent episodes of fever
Prevent mosquito from breeding, nets
4 methods to prevent spread of diseases
Hygiene e.g washing hands are toilet, before cooking; isolating infected; destroying vectors; vaccination
What type of genetic material do viruses have? What to protect it?
DNA/RNA
Protein coat (capsid)
Agrobacterium tumefaciens cause what?
Crown galls- mass of unspecialised cells that grow between root and shoot of plant
How do humans prevent infection?
Tears with enzymes to kill bacteria
Stomach- hydrochloric acid, kills bacteria in food& swallowed mucus
Trachea- goblet cells produce sticky mucus, traps bacteria
How to white blood cells treat infection?
Phagocytosis- phagocytes engulf, digest and destroy pathogens
Lymphocytes- produce complementary antibodies and antitoxins
Causes of disease in plants
Viruses, bacteria, fungi, mineral deficiencies, insect pests
2 mineral deficiencies
What they are needed for and what they can cause
Nitrates
For amino acids production, protein synthesis, stunted growth
Magnesium
For chlorophyll, causes chlorosis, leaves yellow, stunted growth
Physical plant barriers
Cell walls, tough waxy cuticle on leaves, dead cells around stems can fall off
Chemical plant barriers
Antibacterial chemicals, poisons to deter herbivores
Mechanical plant barriers
Thorns and hairs deter animals, leaves curl when touched
Culture
To grow in very large numbers so scientists can see all the bacteria as a whole
Exponential growth
The rate of increase getting larger each time
Aspetic technique
Procedures to ensure there is no contamination
Culture medium
A liquid or gel with the nutrients that bacteria need
How to calculate rate of division
- Convert units to minutes
- Calculate no. of divisions
- Bacteria at beginning x 2 to power of no of divisions
Zone of inhibition
πr²
4 things bacteria need to survive
Suitable pH
Suitable temperature
Nutrients
Oxygen
How to prepare uncontaminated bacteria culture
- Sterilise petri dish, agar gel, spray bench
- Pass inoculating loop through bunsen burner
- Dip loop in bacteria and spread on agar gel
- Lid, tape, upside down at 25 degrees for school
How to test the effect of antibiotics
- Soak filter paper disks in antibiotic solutions
2.Place filter paper discs on sterilised petri dish with bacteria on it
3.Incubate at 25 degrees
4.Calculate zone of inhibition, largest is best
4 ways to prevent bacterial growth
Increase/decrease temp
Use disinfectant- in the environment around us
Use antiseptic- on human skin
Use antibiotics- inside our bodies
What did Ignaz Semmelweis do?
-insisted his students wash their hands before delivering babies
What did Louis Pasteur do?
Showed microorganisms caused disease and developed vaccines
What did Joseph Lister do?
Showed antiseptic chemicals destroy pathogens
3 ways to identify plant diseases
Refer to gardening manual
Take infected to a lab
Use monoclonal antibody testing kits
2 insect pests and what they cause
Aphids- feed on phloem sap, deprive plant of glucose, act as vectors
Nematode worms- feed on roots, plants can’t get water
