B5 communicable diseases Flashcards

1
Q

What is the difference between communicable diseases and non-communicable diseases?

A

Communicable diseases are caused by pathogens that can be passed from one person to another

Non-communicable diseases cannot be transmitted from one person to another

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are some factors that can affect health?

A

diet
-lack of nutrients, food, ED, obesity
stress
-too much, linked to range of health problems (heart disease, cancer)
life situations
-area, gender, financial status, ethnic group, level of free health care
(communicable diseases- diarrhoea, malaria)
(non communicable diseases- heart disease, cancer)
illness

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

What is a communicable disease?

A

it is an infection that is caused by pathogens such as bacteria and viruses
can be passed from one person to the other (infectious)
(tuberculosis, flu)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is a non-communicable disease?

A

cannot be transmitted from one person to the other
(heart disease, arthritis)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What illnesses can viruses lead to?

A

can trigger changes leading to cancers
HPV (human papilloma virus-> cervical cancer)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

What can defects in the immune system be the result of?

A

-genetic makeup
-poor nutrition
-infection (HIV/AIDS)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What can defects in the immune system lead to?

A

higher risk of suffering from communicable diseases

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are immune reactions caused by?

A

pathogens
ie reaction to common cold

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

What can immune reactions lead to?

A

trigger allergies to environmental factors
cause skin rashes, hives, asthma

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

How are physical and mental health linked?

A

severe physical ill health can lead to mental illnesses (depression etc)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

What does malnutrition lead to?

A

health issues
-deficiency diseases
-weakened immune system
-obesity
-cardiovascular diseases
-type 2 diabetes
-cancer

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What are microorganisms that cause disease called?

A

Pathogens
infect animals and plants, causing disease

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

What are some examples of pathogens?

A

bacteria, viruses, protists, fungi

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What are communicable diseases caused by?

A
  • directly by a pathogen
  • by a toxin made from a pathogen
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

How are communicable diseases passed?

A

from one infected individual to another uninfected individual

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What are some examples of communicable diseases?

A

-common cold, tonsillitis
-tetanus, influenza, HIV/AIDS

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

What is an example of a communicable disease passing between different species?

A
  • infected dogs can pass rabies onto people
  • tuberculosis can pass from badgers to cows, cows to people
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

What are the most common pathogens in plants?

A

viruses and fungi

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

What are bacteria?

A

single celled living organisms
smaller than animal and plant cells
living (can survive outside a host)
can be treated by antibiotics

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

What are some uses for bacteria?

A
  • make food (yogurt, cheese)
  • treat sewage
  • make medicine
  • decomposers in the environment and body
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What are the most common pathogens in humans?

A

Bacteria and Viruses

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

What is a virus?

A

even smaller than bacteria
non living
cannot be treated by antibiotics

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

How do bacteria cause disease inside the body?

A

-divide rapidly by splitting in 2 (Binary fission)
-may produce toxins that affect the body (cause symptoms)
- sometimes directly damaging the cell

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

How do bacteria divide/reproduce?

A

binary fission

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

How does a virus cause disease inside the body?

A
  • take over the cells in the body
  • live and reproduce inside the cell
  • damage and destroy cells
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What are common symptoms of disease?

A
  • high temperature
  • headaches
  • rashes

caused by the body responding to the pathogens toxins and cell damage

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

How do pathogens spread?

A

Through the air
-droplet infection, human expel tiny droplets with pathogens from breathing system when coughing, sneezing or talking. Others breathe in the droplets
-flu, influenza, common cold

Direct contact
- common in plants
-infected leaf left in field can infect entire new crop
-humans, STI (syphilis, chlamydia), direct contact of skin
-HIV/AIDS, hepatitis enter through direct sexual contact, bodily fluids (cuts, scratches, needle punctures)
-animals can be a vector of plant and animal diseases (carrying pathogen between infected and uninfected individuals)

By water
-plants. fungal spores carried in splashes of water
-humans, eating raw, uncooked, contaminated food. Drinking water containing sewage
(salmonella, cholera)
- enters through digestive system

Lifestyle factors
- crowded living conditions, no sewage system etc

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What is a vector?

A

a carrier of a pathogen between infected and uninfected individuals, can be between different species
can carry plant and animal pathogens
(ie mosquito)

29
Q

What is a culture medium?

A

a liquid or gel containing nutrients

30
Q

What are conditions microorganisms need to grow?

A
  • warmth
  • oxygen
  • culture medium (carbohydrate, minerals, nitrogen source, chemicals)
31
Q

How can cultures become contaminated?

A

skin, air. soil, water around

32
Q

What is a mutation?

A

a change in the DNA

in pathogens it can create a new and dangerous pathogen

33
Q

Why is the maximum temperature for culture incubation in schools 25 degrees C?

A
  • 37 degrees is human body temperature
  • high risk of growing dangerous pathogens
  • low temp, reduce risk of growing harmful bacteria
34
Q

Why are industries allowed to incubate cultures at 37 degrees C?

A
  • enables microorganisms to grow quicker
  • can be used for use faster
35
Q

What is the growth rate of bacteria affected by?

A
  • temperature
  • available nutrients
  • oxygen levels
  • pH
36
Q

How can you prevent the growth of bacteria?

A

-raise or lower the temperature
- chemicals to stop them growing/killing them (disinfectant for environment around, antiseptic for human skin, antibiotics inside the body)

37
Q

Ignaz Semmelwies + what did he discover?

A

He was a doctor mid 1850’s
-Many women were died from childbed fever a few days after birth, no cause
-he noticed medical students didn’t wash their hands between dissecting corpses to delivering babies. He thought they could be carrying disease from the bodies to the patients
- he insisted medical students wash their hands before delivering babies

38
Q

Louis Pasteur + Joseph Lister -> what did they discover?

A

Mid to late 19th century
Louis Pasteur: showed microorganisms caused disease, developed vaccines (anthrax, rabies)
Joseph Lister: used antiseptic chemicals in operating theatres to destroy pathogens before causing any infection

39
Q

How can hygiene prevent the spread of communicable diseases?

A
  • hand washing (after toilet, before cooking, after animal contact etc)
  • using disinfectant (kitchen surfaces, toilets, reduce number of pathogens)
  • keeping raw meat away from food eaten uncooked (prevent pathogen spread)
  • coughing/sneezing into handkerchief, tissue, hands (then wash hands)
  • maintaining hygiene of people and agricultural machinery (prevent spread of plant disease)
40
Q

How can isolating infected individuals prevent the spread of communicable diseases?

A

-less amounts of healthy people come into contact with them
-less likely pathogens pass on

  • same for plants
  • only works for small, movable plants
41
Q

How can destroying or controlling vectors prevent the spread of communicable diseases?

A

spread of diseases can be prevented or reduced
- houseflies carry human disease
- mosquitos carry a range of disease (malaria, dengue fever)

42
Q

How do vaccination work to prevent the spread of communicable diseases?

A
  • doctors introduce a small amount of dead or inactive form of a specific pathogen to the body
  • prepares the immune system for the live pathogen. If there becomes contact with live pathogen, body won’t be ill
  • success protecting large numbers of humans and animals
  • cannot protect plants, no immune system
43
Q

What is Measles and how is it spread?

A
  • fever, red rash
  • spreads through droplet infection
  • can cause blindness, brain damage, death
  • no treatment, if infected then person must isolate
    -rare in the UK
44
Q

What is HIV/AIDS?

A
  • HIV leads to AIDS
  • HIV: mild, flu like illness, attacks immune cells. remains inside immune system until system is so badly damaged it can’t deal with other infections, or cancers.
  • Then it has become AIDS
    onset of AIDS depends on
  • level of nutrition
  • overall health
  • access to antiretroviral drugs
45
Q

How is HIV spread?

A
  • direct sexual contact, exchange of bodily fluids (ie blood, drug users share needle, unscreened blood used for transfusion)
  • passed from mother to child from breast milk

no cure, spread can be prevented
-use condoms
- not sharing needles
- screening blood
- HIV positive mothers bottle feeding children

46
Q

What is TMV?

A
  • widespread plant pathogen affecting over 150 species of plants (ie tomatoes, tobacco plants)
  • causing distinct mosaic patterns on leaves, virus destroys plant cells
  • affects the growth of the plant, affected areas don’t photosynthesise, reducing crop yield
47
Q

How is TMV spread?

A
  • by contact between diseased plants and healthy plants
  • insects can act as vectors
  • virus can remain infection in soil for about 50 years
  • no treatment, farmers now grow TMV restraint-strains, also good field hygiene and good pest control prevents spread.
48
Q

What are Salmonella?

A
  • bacteria that live in the guts of many different animals.
  • found in raw meat, poultry, eggs and egg products (mayonnaise)
  • can cause salmonella food poisoning if ingested
  • causes of infection: eating undercooked food, eating food prepped in unhygienic conditions
49
Q

Salmonella + symptoms?

A

symptoms develop within 8-72 hours
- abdominal cramps, vomiting, diarrhoea
- caused by secreted toxins
- can be fatal in young children and elderly
- more serious in countries with malnutrition

50
Q

What are ways of preventing Salmonella?

A
  • poultry are vaccinated against Salmonella in the UK
  • keep raw chicken away from food eaten raw/uncooked
  • avoid washing raw chicken
  • wash hands and surfaces thoroughly
  • cook chicken thoroughly
51
Q

What is Gonorrhoea?

A

-STD
- spread by unprotected sexual contact with infected person
- early stages have symptoms, then becomes symptomless
- early symptoms: thick yellow/green discharge from the vagina or penis, pain on urination
- untreated, can cause long term pelvic pain, infertility, ectopic pregnancies

  • bacterial, can be treated with antibiotics, however their are antibiotic resistant strains
  • all sexual partners of infected individual should be treated to prevent further spread
  • prevent spread by using barrier method (condom), reduce number of sexual partners
52
Q

What are examples of bacterial diseases in plants?

A

-rose black spot
-usually found in tropical and sub tropical regions
Agrobacterium tumefaciens- causes crown galls (mass of unspecialised cells between the root and the shoot of growing plants)
-insert plasmids into plant cells, cause mass to grow
-scientists can make use of this: manipulate bacteria so they carry desirable genes to infect plant cells with.

53
Q

What are fungal diseases + examples?

A

Athletes foot- fungal skin condition
- fungal diseases can be fatal when attack the lungs or brains or ill people
- can develop damaged heart valves
- antifungal drugs, but hard to treat deep tissue infections

Plants
- common, huge crop areas are lost yearly
- stem rusts, rotting diseases

54
Q

What is Rose black spot?

A

fungal disease of rose leaves
- causes purple/black spots on leaves
- bad for gardens or commercial flower growers
- leaves often turn yellow, drop early, reduces photosynthesising area, plant doesn’t flower well

  • spores carried by wind, spread by rain drops splashing from leaf to leaf.
  • stay dormant over winter on stems and dead leaves
  • can prevent by burning or removing dead leaves, chemical fungicides
  • specially bred roses resistant to black spot, disease still can’t be prevented or cured
55
Q

What are protists?

A

a type of single celled organisms
- cause range of diseases, relatively rare pathogens
- carried diseases often serious and damaging
-usually involve a vector (mosquitos etc) to transfer to host (ie malaria)

56
Q

What is Malaria?

A
  • disease caused by protist pathogens, parasites (live and feed on other living organisms)
  • lifecycle-> time in human body and time in female mosquito body
  • reproduce sexually in mosquito but asexually in human body
  • mosquito feeds 2 meals of human blood before laying eggs, protist passed into bloodstream
  • protist travels human body through bloodstream
  • protists burst out of blood cells: causes human body a fever and shaking
  • can be fatal or weakening
57
Q

How can Malaria be treated?

A
  • combination of drugs (not always available in countries with malaria problems)
  • Protists can become resistant
  • using insecticide-impregnated mosquito nets (prevent mosquitos biting humans
  • use insecticide to kill mosquitos in home, office etc
  • remove standing water, spray water with insecticide to kill larvae (remove breeding ground)
  • antimalarial drugs (travellers), kills parasites if in blood.
58
Q

What are the skin defences to pathogens?

A
  • barrier. prevents bacteria and viruses reaching tissue beneath. Cuts break barrier, restored by body by platelets to clot the cut and scab. Forms a seal over the cut, stops pathogens entering
  • antimicrobial secretions to destroy pathogenic bacteria
  • healthy skin is covered with microorganisms, help keep healthy, act as an extra barrier to pathogens
59
Q

What are respiratory and digestive system defences to pathogens?

A
  • nose hairs, produce mucus. Hair + mucus trap air particles that may contain pathogens or irritate the lungs. (working in pollution, snot becomes black, proves defence works)
    -Trachea and Bronchi also secrete mucus, trap air pathogens. Cilia line them, they beat to waft mucus up to back of throat to be swallowed
  • stomach produces acid, destroys microorganisms in swallowed mucus, also any other ingested.
60
Q

What are immune system defences against pathogens?

A
  • second line of defence: white blood cells
    WBC
    -Ingest microorganisms: ingest, digest and destroy pathogens so they can’t make you ill
    -Produce antibodies: target particular bacteria/viruses + destroy them. Unique antibody to each pathogen. If made once, can be quickly made again if repeatedly infected, stopping getting ill twice.
    -Producing antitoxins: counteract the toxins produced by the pathogens
61
Q

What are examples of plant pathogens?

A

Aphids
- sharp mouthparts, penetrate phloem vessels so they can feed on sugar rich phloem sap
- attack in huge numbers, depriving plant cells of photosynthesis products
- vector (transfer virus, bacteria and fungi on their mouthparts)

Worms and insect larvae
- live in the soil
- feed in or on plant roots
- cannot absorb water or mineral ions effectively (damaged)
- plant fails to grow/thrive

62
Q

How can aphids be destroyed?

A

-chemical pesticides
- biological pest control (enclosed space ie greenhouse)
- release aphid eating insect (ie ladybug + their larvae) to control population, doesn’t impact crop success
-

63
Q

How does mineral deficiency lead to non communicable diseases in plants?

A
  • Plants take magnesium ions form soil to make chlorophyll needed for photosynthesis.
  • If level of ions in soil is low, plant cannot make enough chlorophyll
  • Leaves become yellow, growth slows due to lack of photosynthesis

CALLED CHLOROSIS

  • level of ions can be replaced with soil fertilisers, but if not replaced then plant will eventually die
64
Q

What are symptoms of plant disease?

A
  • stunted growth (mineral deficiency)
  • spots on leaves (black rose spot)
  • areas of decay or rotting (black rose spot, potato blights)
  • growths (crown galls caused by bacterial infection)
  • malformed stems and leaves (due to aphid infestation etc)
  • discolouration (chlorosis, tmv)
  • presence of visible pests (aphids, caterpillars etc)
65
Q

How can disease in garden plants be identified?

A

by comparing symptoms in living plant with disease description in gardening manual/online

66
Q

How can disease be identified in crop plants or forest trees?

A
  • experts visit area to observe natural environment
  • test samples of diseased material in lab, to identify pathogen (DNA analysis etc)
67
Q

What are physical barriers in plants against pathogens?

A
  • cellulose wall strengthens plant cells, also resist invasion of microorganisms (aphids break barrier, give pathogens way into cells)
  • Tough waxy cuticle on leaf surface, acts as barrier to pathogen entryway. Only access at stomata
  • Bark on trees, layer of dead cells on outside of stems, hard for pathogens to penetrate. When cells are shed, pathogens fall too
  • Leaf fall, deciduous trees lose leaves in autumn, any leaf infection fall off tree with leaves.
68
Q

What are chemical barriers in plants against pathogens?

A
  • produce antibacterial chemicals, protecting pathogen invasion
  • plant uses as antibiotics (mint, witch hazel= mild antiseptics in cosmetics)
69
Q

How do plants defend themselves against herbivores?

A
  • poison deters herbivores (foxgloves, deadly nightshade)
  • thorns make it unpleasant, painful to eat the plant (brambles, cacti), may not deter insects
  • hairy stems and leaves deter eating, laying eggs. Can combine with poison (nettles)
    -drooping or curling when touched (frightening animals)
  • Mimicry, plants droop to mimic unhealthy plants. Can mimic butterfly eggs to avoid others laying on them