Fungi

Question 1

are fungi eukaryotic?

Answer 1

yes

Question 2

what are the 3 major groups of fungi?

Answer 2

moulds, yeast, mushrooms

Question 3

are fungi ubiqutious?

Answer 3

yes

Question 4

how do fungi survive?

Answer 4

• they secrete hydrolytic enzymes that allow them to solubilise substances
• they are usually aerobic
• can be facultative anaerobe (can obtain energy by fermentation - yeast)

Question 5

fungi can be either…

Answer 5

saprophytic or parasitic

Question 6

what is a saprophytic fungi?

Answer 6

uses dead organic matter as a nutrient source

Question 7

what is a parasitic fungi?

Answer 7

live on another organism

Question 8

what is the fungal cell wall like?

Answer 8

very rigid - provides rigidity and structure, they have lots of layers, 80-90% polysaccharide, also contains chitin, glucans (mannans, galactosans), cellulose, mannans

Question 9

what is the fungal cell membrane like?

Answer 9

similar to eukaryotes, has 6% sterol composition, ergosterol instead of cholestrol which could be a selective target for drug design, it also regulates osmotic pressure

Question 10

what is the shape of yeast?

Answer 10

spherical, oval or cylindrical in shape, 3-30micrometers, they are unicellular fungi , it can produce sexually and asexually

Question 11

what is the shape of moulds?

Answer 11

they consist of branched, thread like filaments called hyphae which form a mycelium.
it has lots of nuclei - multinucleate so can rapidly divide

Question 12

what are hyphae?

Answer 12

branched, thread like filaments

Question 13

what do all the hyphae together form?

Answer 13

a mycelium

Question 14

what is the difference between septate and coenocytic?

Answer 14

septate (with cross walls) or coenocytic (continous cytoplasm)

Question 15

when do mushrooms occur?

Answer 15

when conditions are favourable

Question 16

how do fungi reproduce sexually?

Answer 16

a mixing of genetic material occurs so that the offspring exhibit traits of both arents.

Question 17

many species of fungal can use both sexual and asexual reproduction at different times. True or false?

Answer 17

tru

Question 18

what mechanism do yeast use to asexually reproduce?

Answer 18

fission and budding

Question 19

moulds have unique reproductive structure. true or false

Answer 19

true

Question 20

can yeast become resistant really quickly?

Answer 20

yes

Question 21

how do moulds reproduce?

Answer 21

asexually, exospores (conidia) are involved. they occur from fusion of unicellular gametes or specialised hyphae

Question 22

what do spores depend on?

Answer 22

specie

Question 23

what are the 2 types of spores?

Answer 23

acospores - formed in enclosed sac

- basidiospores - formed in club shaped baidium

Question 24

what is yeast used in industrially?

Answer 24

fermentation (beer, wine bread) & genetic engineering

Question 25

what can molds do medically to us?

Answer 25

colonise us - causing superficial (surface layer of the body) mycoses Hypersensitivity - fungal spores, mycelial fragments -toxins

Question 26

what is a candidiasis?

Answer 26

a yeast infection, they can be superficial such as oral or vaginal thrush, or systemic and potentially life-threatening diseases.

Question 27

who are most vulnerable to candida infections?

Answer 27

immunocompromised, such as cancer, transplant, and AIDS patients, are vulnerable

Question 28

how is candidiasis treated?

Answer 28

commonly treated with topical clotrimazole, topical nystatin, fluconazole and topical ketoconazole.

Question 29

what can we target in fungi to get rid of them?

Answer 29

ergosterol, bc human cell dont have that, its found in membranes instead of cholestrol

Question 30

some antifungal drugs and causse they target

Answer 30

Polyoxins: inhibit chitin biosynthesis (not used clinically) 5-fluorocytosine: nucleic acid synthesis inhibitor Emergence of resistance

Question 31

what is yeasts' dimorphism?

Answer 31

yeast can either grow as a yeast (single cells) | or they can form a mycelial and grow together.

Question 32

at body temperature, how does candida albicans grow?

Answer 32

it forms a mycelial, making it more pathogenic that can invade our tissues, allow it to reproduce more rapidly , gives a competitive advantage