Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Biology A-Level OCR > Disease > Flashcards

Disease Flashcards

You may prefer our related Brainscape-certified flashcards:
AP® Biology flashcards Biology 101 flashcards
1
Q

What are the types of pathogens?

A

Bacteria, fungi, protoctista and virus

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

What are the different shapes of bacteria?

A

Rod, chain, coccus, pair of cocci, cluster of cocci, comma shaped, spiral, corkscrew

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

How can bacteria be classified?

A

Shape or cell wall

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

How can bacteria be classified by their cell wall?

A

Gram staining - gram positive (purple-blue) or gram negative (red)

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

Name an example of a gram positive and a gram negative bacteria

A

Gram positive: MRSA

Gram negative: E.coli

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

What are the properties of viruses?

A

0.02-0.3 micrometers, 50x smaller than bacteria, reproduce within host cells

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

What are the properties of protoctista?

A

Eukaryotic, single celled or multicellular, use host cells to reproduce

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

What are the properties of fungi?

A

Eukaryotic, often multicellular, often saprophytes (eats dead matter), some are parasitic

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

How do viruses infect cells?

A

Inject viral genetic material into host cell (and so host DNA), virus then uses the host cell to make new virus cells, which causes cell lysis

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

How do protoctista infect cells?

A

Use host cells to reproduce and the cause cell lysis, but does not take over host cell’s DNA. Digest and use cell contents as they reproduce

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

How do fungi infect cells?

A

Digest living cells and destroy them

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

How do bacteria infect cells?

A

Produce a poison that damages host tissues, either by breaking down cell membranes, inactivate enzymes or damage host cell’s genetic material so the cells cannot divide

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

What are the outcomes of plant diseases?

A

Starvation, loss of jobs (so failing economy) and danger to ecosystems

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

Name an example of a plant bacterial disease

A 
Ring rot (gram positive)
Symptoms include: damages leaves, tubers and fruit
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Name an example of a plant viral disease

A

Tobacco mosiac virus

Symptoms: Damages leaves and fruit, stunts growth and yield

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

Name an example of a plant disease caused by a protoctista

A 
Potato blight (tomato/late blight)
Symptoms: Destroys leaves, fruit and tubers
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Name an example of a plant fungal disease

A

Black sigatoka

Symptoms: Destroys leaves (turning them black), reduced yield

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Name an example of an animal bacterial disease

A

Tuberculosis (TB, mycobacterium tuberculosis)

Symptoms: Damages lung tissue, suppresses immune system

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

Name an example of an animal viral disease

A

HIV/AIDS

Symptoms: more susceptible to other diseases

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

Name an example of an animal disease caused by a protoctista

A

Malaria (vector of mosquitos)

Symptoms: rolling fevers

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Name an example of an animal fungal disease

A

Ring worm

Symptoms: Grey-white, crusty circular areas of skin

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

How are diseases spread?

A

Indirect and direct transmission

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

What are some examples of direct transmission in animals?

A

Direct contact, inoculation, ingestion

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

What are some examples of indirect transmission in animals?

A

Fomites (inanimate objects like bedding, socks), droplet infection, vectors

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

What are some of the factors affecting the transmission of disease in animals?

A

Overcrowding, malnutrition, poor immune system, little/no waste disposal, climate change, culture and infrastructure, socioeconomic factors

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What are some examples of direct transmission in plants?

A

Direct contact between parts of a healthy plant with parts of a diseased plant

27
Q

What are some examples of indirect transmission in plants?

A

Soil contamination, vectors

28
Q

Name some examples of vectors for indirect disease transmission in plants

A

Wind, water, animals and humans

29
Q

What are some of the factors affecting the transmission of disease in plants?

A

Susceptible plant breeds, over-crowding, poor mineral nutrition, damp/warm conditions, climate change

30
Q

How do plants prevent disease?

A
  • pathogen recognised by glycolipid
  • and compounds of broken down cell wall from pathogenic enzymes are recognised
  • signalling molecules alert plant cell’s nucleus
  • nucleus triggers production of callose and lignin to block plasmodesmata to prevent pathogen entering
  • chemical is secreted to alert other plant cells
31
Q

What are the properties of plants physical defence?

A

Polysaccharide with beta 1-3 and 1-6 glycosidic bonds between glucose monomers

32
Q

What are some chemical defenses in plants?

A

Insect repellents (pine resin), insecticides, antibacterial compounds, antifungal compounds (chitinases), anti-oomcytes (glucanases), general toxins

33
Q

What are some non-specific defenses in animals? (keep out)

A

Skin, mucus, tears/stomach acid, blood clotting, inflammation, expulsive reflexes

34
Q

How is skin a non-specific defense? (keep out)

A

Covers areas of body to prevent pathogens entering, skin flora of microorganisms to outcompete, sebum (oil) to inhibit growth of pathogens

35
Q

How is mucus a non-specific defense? (keep out)

A

Sticky to trap pathogens, contains lysozymes to digest pathogens

36
Q

How are tears/stomach acid a non-specific defense? (keep out)

A

Lysozymes (also applies to urine)

37
Q

How are expulsive reflexes a non-specific defense? (keep out)

A

Expulsive reflexes (sneezes, coughs, vomiting and diarrhoea) expel contents of body that may contain pathogens

38
Q

How is blood clotting a non-specific defense? (keep out)

A

Blood clots seal a wound that pathogens may enter by

39
Q

What is the cascade response for blood clotting?

A

1 - injury
2 - Platelets aggregate
3 - Triggers the release of serotonin and thromboplastin
4 - Serotonin causes muscles to contract for ease of clot formation
5 - Converts inactive prothrombin into active thrombin
6 - Active thrombin converts fibrinogen into fibrin (collagen fibers)

40
Q

How is inflammation a non-specific defense? (keep out)

A

Histamines make blood vessels dilate, which causes heat to prevent pathogens reproducing. Histamines also cause blood plasma to move out of the vessels (tissue fluid) which causes swelling and pain. Cytokines attract white blood cells to the site to dispose of the pathogens via phagocytosis

41
Q

What are some other non-specific defenses in animals? (getting rid)

A

Fevers and phagocytosis

42
Q

How are fevers a non-specific defense? (getting rid)

A

Pathogens cannot reproduce at a higher temperature (most often above 37 degrees) and specific immune system works faster at higher temperatures (caused by cytokines)

43
Q

What is phagocytosis?

A

A process where specialised white blood cells (phagocytes) engulf and destroy pathogens (neutrophils and macrophages)

44
Q

List the stages of phagocytosis

A

1 - Pathogens produce chemicals that attract phagocytes
2 - Phagocytes recognise foreign proteins on the pathogen
3 - Phagocyte engulfs pathogen and encloses it in a vacuole called a ‘phagosome’
4 - The phagosome combines with the lysosome to form a phagolysosome
5 - Enzymes from the lysosome digest and destroy the pathogen

45
Q

What are cytokines?

A

Act as cell-signaling molecules that alert other phagocytes that there are foreign bodies within the organism. Can also increase body temperature

46
Q

What are opsonins?

A

Chemicals that bind to pathogens and ‘tag’ them so they can be more easily recognised by pathogens. Phagocytes have receptors in their plasma membranes that are complementary to common opsonins

47
Q

What are antibodies?

A

Molecules that bind to foreign antigens so the immune system know which cells to attack, form an antigen-antibody complex when binds to antigen

48
Q

What is the structure of antibodies?

A

Light chain, heavy chain, variable and constant region, receptor binding site and antigen binding site (and flexible hinge regions)

49
Q

How do antibodies defend the body?

A

1 - antigen-antibody complex acts as an opsonin
2 - Antigen-antibody complex makes it difficult for pathogens to invade host cells
3 - Antigen-antibody complex causes pathogens also carrying the complex to clump together, so acts as an agglutinin
4 - antibodies bind to toxins produced and so makes them harmless

50
Q

What are lymphocytes?

A

Specialised white blood cells, come as B and T lymphocytes

51
Q

Where are lymphocytes made?

A

B - Bone marrow

T - Thymus gland

52
Q

What are the different types of T lymphocytes?

A

T helper, T killer, T memory and T regulator

53
Q

What are the different types of B lymphocytes?

A

Plasma cells, B effector and B memory

54
Q

What is the function of T helper cells?

A

Bind to pathogen’s plasma membrane and produce interleukins (a form of cytokine) to stimulate the activity of B lymphocytes to increase antibody production and other T lymphocytes

55
Q

What is the function of T killer cells?

A

Produces perforin, which kills the pathogen by making holes in the plasma membrane

56
Q

What is the function of T memory cells?

A

Live for a long time in the blood (immunological memory) and divide rapidly into T killer cells when in contact with the pathogen again

57
Q

What is the function of T regulator cells?

A

Interleukins are involved in supressing the immune system to regulate and prevent host antigens being attacked

58
Q

What is the function of plasma cells?

A

Produce antibodies that are complementary to antigens (can produce 2000 antibodies per second)

59
Q

What is the function of B effector cells?

A

Divide to form plasma cell clones

60
Q

What is the function of B memory cells?

A

Live for a VERY long time (immunological memory) and have a very specific response when a specific foreign antigen enters the host again

61
Q

What is the difference between cell-mediated and humoral immunity?

A

Cell mediated: pathogens/changes within cells

Humoral immunity: responds to antigens found outside of host cells

62
Q

In humoral immunity, what is a primary and secondary immune response?

A

Primary immune response: slower, first response

Secondary immune response: very quick, no symptoms

63
Q

What is an autoimmune disease?

A

When the immune system confuses self-cells with foreign cells and so attacks healthy body tissue

64
Q

Name some examples of autoimmune disease

A

Type 1 diabetes, rheumatoid arthritis, lupus

Biology A-Level OCR (26 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions