Biology - Diseases

Question 1

what is a disease?

Answer 1

anything that causes an organism to stop its normal functions

Question 2

what is an infectious disease?

Answer 2

any disease that can be transmitted or spread to other organisms

Question 3

how does bacteria work?

Answer 3

a unicellular organism with thousands of different species. only a handful cause disease, called pathogenic bacteria or pathogens. diseases that can spread are labelled infectious disease.

Question 4

how do viruses work?

Answer 4

responsible for many illnesses, colds, flu, measles, mups, rupella, warts, chickenpox, covid 19. are pathogens which are 100 times smaller than bacteria. viruses can only grow and reproduce inside cells they have invaded (host cells).

Question 5

how do protozoa work? give examples

Answer 5

see lesson 2
single celled animal cells which are amoeboid or have cilia or flagella. For example, Malaria is when a unicellular parasitic organism called Plasmodium that mosquitoes carry. injected into the host when mosquitoes suck the blood.

Question 6

how do we counteract disease? hint: three lines of defence

Answer 6

see lesson 2
first line of defence -
lachrymal glands
mucus
saliva
acid
skin

second line of defence -
neutrophils

third line of defence -
lymph
spleen
lymphatic system

Question 7

what do we take if the immune system isn’t enough? describe each

Answer 7

vaccines - chemicals that cause your body to react as if it had met a pathogen, so immune system responds to the vaccine by making antibodies so you can become immune to the pathogen
antibiotics - substance that kills bacteria or prevents the growth of bacteria
antivirals - drug used to treat infections caused by viruses

Question 8

do antivirals and antibiotics have the same effect?

Answer 8

no

Question 9

what are the 4 key types of disease

Answer 9

bacteria
virus
protozoa
fungus