Diseases

Question 1

Communicable disease

Answer 1

Can be passed from one organism to another, in animals

Often from one individual species to another but some BETWEEN species - vectors

Question 2

What is a communicable disease?

Answer 2

Can be passed from one organism to another, in animals- often from one individual to other, in animals. Often from one individual of a species to another -but some BETWEEN species- vectors

Question 3

Types of pathogen

Answer 3

Bacteria, Virus, Protoctista, Fungi

Question 4

Bacteria

Answer 4

Prokyaryotes
Don’t have a membrane bound nucleus/organelles
Damage host by releasing waste products and toxins
Live in vascular tissues and causes BLACKENING and deaths of tissues

Question 5

How are bacteria classified?

Answer 5

By their basic shape- rod, spherical, comma shaped, spiralled, corkscrew

By their cell walls-2 main types of bacteria cell have different structures - react differently to gram staining

Question 6

Gram staining

Answer 6

Gram positive bacteria look blue-purple under light microscope e.g. MRSA
Gram negative bacteria- red e.g. gut bacteria E.coli
Type of cell wall affects how bacteria reacts to different antibiotics

Question 7

Viruses

Answer 7

Genetic material surrounded by a coat of protein
Cannot reproduce without cells
0.02-0.3um in diameter
50 time smaller than an average bacterium
Viruses reproduce rapidly and evolve by developing adaptations to their host

Question 8

How do viruses destroy cell

Answer 8

Invade living cells, where the genetic material of the virus takes over biochemistry f host cell t make more viruses

Question 9

Protoctista

Answer 9

A group of eukaryotic organisms with a wide variety of feeding methods
Includes single celled organisms and cells groups into colonies
Enter host and feed on contents as they grow
Mauy need a vector
Parasitic - use animals as host

Question 10

Fungi

Answer 10

Eukaryotic and multicellular
Yeasts that cause human iseases are single celled
Cant phosynthesise, digeest good EXTRACELLULARLY before absoribing teh nutrients
Many fungi are sprophytes =feed on dead and deayign matter
Parasitic
Fungal infections often affect the leaves of teh plant and stop them photosyntehsis - quickly killplant
Reproduce = millions of tiny spores
Netweork of fibre fialment called hyphae formin the mycellium

Question 11

Damaging host tissue directly

Answer 11

VIRUSES- Take over cell metabolism
-The viral genetic material gets into the host cell and inserted into host DNA , Virus then uses host cell to make new viruses which burst out if cell

PROTOCTISTA -Take over cells and break them open as the new generation emerge, but they do not take over the genetic material of the cell. DIgESt and use cell contents as they reporduce e.g, malaria

FUNGI - Digest living cells and destroy them

Question 12

Producing toxins which damage host tissue

Answer 12

BACTERIA- Produce toxins that posion or damage the host cell in some way, causign disease
- Somr damage the host cells by breakign down the cell memrbanes , sme inactivate enzymes and sme interfere with the gentic info so cellw ont divide

FUNGI - Some fungi produce toxins which affect the host cells and cause disease

Question 13

Plant bacterial disease

Answer 13

RING ROT

Question 14

RIng rot

Answer 14

Bacterial disease of potatoes , tomatoes and aubergines
Gram positive
Transmissin= direct contact, cotnaminated potato waste/water supply
EFFECT= Vascular tissues appear glassy and eater soaked. 80% of crops destroyed
SOLUTION- No cure, practice good hygeine and plant only classified seeds

Question 15

Plant virus

Answer 15

Tobacco mosaic virus

Question 16

TMV

Answer 16

Infects tobacco plants and 150 other specieis
e.g. tomatoes, peppers, cucumbers
Damages laves, flowers
Transmission- water and via plant and plant seeds
solution- resistant crop strains, good hygiene , regularly inspect plant and burn infected plants

Question 17

Potato /tomato blight

Answer 17

protoctista 
Water rot, brown lesions 
Hyphae penetrate host cells 
Fungal spores by wind 
No cure

Question 18

Tuberculosis

Answer 18

Bacterial disease of humans, cows, pigs
Effect -damages and destroys lung tissues and and suppresses the immune system so the body iks less’s able to fight off diseases
Global rise of HIV/AIDS has a large impact on tose suffering from Tb
Antibiotics

Question 19

Types of pathogens

Answer 19

Fungi
Bacteria
Protoctista
Virus

Question 20

Bacteria ?

Answer 20

Prokaryotic
DO NOT have a membrane bound nucleus/organelles
Damage host by releasing waste products and toxins
Live in vascular tissues and causes BLACKENING and deaths of tissues

Question 21

How are bacteria classified

Answer 21

By basic shape - may be rod shaped, spherical, comma shaped, spiralled and corkscrew

By their cell walls- 2 main types of bacteria cell wall have different structures and so react differently to gram staining

Question 22

Gram staining

Answer 22

Gram positive bacteria look blue- purple under light microscope e.g. MRSA

Gram negative- red e.g. Gut bateria E.coli

Type of cell wall affects how bacteria reats to different antibiotics

Question 23

What are the modes of action for damaging that pathogens can take

Answer 23

Damaging host cells directly

Releasing toxins which damage host tissue

Question 24

Damaging host tissues directly - Modes of action for pathogens

Answer 24

VIRUSES- Take over cell emtbolism
The viral genetic material gets into the host cell and inserted into host DNA. Virus then uses the host cll to make new viruses which burst out of cell-infect more

PROTOCTISTA- take over cells and break them open as the new generation emerge - dont take over the genetic material, digest and use

FUNGI- Digest living cells and destroying them

Question 25

Producing toxins which damage host tissue- pathogens, modes of transport

Answer 25

BACTERIA- Produce toxins that poision or damage the host cell in some way, causing disease
- Some bacterial toxins that damage the host cell by breaking down the cell membranes, some damage enzymes, some interfere with the host cell genetic info so cells cant divide

FUNGI - Some fungi produce toxins which affect the host cells and cause disease

Question 26

Black sigatoka

Answer 26

Banana disease
FUNGUS
Effect- brown rusty paint liek spots, attacks and destroys eaves- hypahe penetrate and digest cells turning them black
50% reduction in yield

SOLUTION- Resistant strains are beign developed

Question 27

HIV/aids

Answer 27

Targets T helper cells in the immune system , gradually destroying
Humans and non human primates
Retrovirus with RNA as its genetic material, contain the enzyme reverse transcript 0 transcribes teh RNA to a single strand of DNA to produce single strand in host cell-
Bodily fluids
No vacccine or cure

Question 28

Malaria

Answer 28

Protoctista plasmodium
Anopheles mosquito
2 hosts - people, and mosquito
Reproduce inside mosquito, when it feeds on blood - plasmodium is passed on
Invades blood cell, liver and brain
200 million get it a year
No vaccine, antimalarial tabs, drain stagnant water

Question 29

Bacterial meningitis

Answer 29

Bacterial infections of the meniges of the brain
an spread into the rest of the body causing septicemia
Blotchy red and purpole rash
10% infected die
Sneezing transmission
Solution = antibiotics

Question 30

Athletes foot

Answer 30

FUNGAL
Form of ring worm 
Grows on and digests warm, moist in between toes 
Contact with infected 
Antifungal medicine

Question 31

Influenza

Answer 31

Virus
Infects ciliated epithelial cells in gas exchange system
Kills them - leaving airways open to second infection
Severe seconadry bacterial infections on top of original
Classified by proteins on surfaces
Vaccine, rest

Question 32

Ringworm

Answer 32

Fungi
Antifungal cream
grey white crusty areas