Chapter 21: Fungi

Question 1

What is a hypha?

Answer 1

a tube of a filament in a fungus

Question 2

What is a mycelium?

Answer 2

visible mass of hyphae

Question 3

What are fungi cell walls made of?

Answer 3

chitin

Question 4

What are the 2 modes of nutrition for fungi?

Answer 4

parasitic and saprophytic

Question 5

Are fungi heterotrophic or autotrophic?

Answer 5

heterotrophic

Question 6

What is a parasite?

Answer 6

an organism that feeds off of a living host

Question 7

What is a saprophyte?

Answer 7

an organism that feeds off of dead organic matter

Question 8

What are the two types of parasite?

Answer 8

obligate parasite - only lives on a live host (can cause harm)
facultative parasite - may kill the host

Question 9

What are saprophytic fungi known as in ecology?

Answer 9

decomposers

Question 10

What is the difference between edible fungi and poisonous fungi?

Answer 10

edible - can be eaten and digested

poisonous - can be eaten but not digested, it causes harm to the body

Question 11

What is an example of an edible fungi?

Answer 11

truffles

Question 12

What is an example of a poisonous fungi?

Answer 12

death cap

Question 13

Name the two fungi studied.

Answer 13

rhizopus

sacchoromyces

Question 14

How does rhizopus get its food?

Answer 14

secretes enzymes into its environment
lives off starchy food
saprophyte

Question 15

What is the function of hyphae?

Answer 15

digests the substrate on which they grow

Question 16

What is the function of rhizoids?

Answer 16

provide extra surface area for absorption of the digested material

Question 17

What is the function of the stolon?

Answer 17

allows rhizopus to spread sideways

Question 18

hyphae are multinucleic, what does this mean?

Answer 18

they have no cross walls and multiple nuclei (n)

Question 19

What is the function of the sporangium?

Answer 19

produces spores

Question 20

What is the mycelium?

Answer 20

hyphae, rhizoids together

Question 21

How does rhizopus reproduce?

Answer 21

asexually - sporulation

sexually - gamete joining

Question 22

What is sporulation?

Answer 22

the sporangium opens to release spores, each spore blows away and it lands on a substrate, if the substrate is suitable, it grows into a new hyphae and mycelium

Question 23

Explain the sexual reproduction of rhizopus. 12 steps

Answer 23

1. hyphae from opposite strains grow close together (+ and - )
2. swelling from opposide each other form
3. the swellings touch
4. nuclei move into each swelling forming progametangia
5. cross walls form to produce gametangia which are held together by suspensors
6. walls between gametangia dissolve
7. fertilisation occurs and produces many diploid zygote nuclei
8. a tough walled black zygospore forms these nuclei
9. zygospores can remain dormant for a long time
10. in favourable conditions zygospores germinate by meiosis
11. haploid hyphae grows, sporangiophore, sporangium
12. spores are released from sporangium

Question 24

What is a progemetangia?

Answer 24

nuclei move into swelling that are touching

Question 25

What is a gametangium?

Answer 25

when the nuclei in the swellings join to form one swelling

Question 26

What is a zygospore?

Answer 26

a spore that is dormant until favourable conditions arise

Question 27

What is another name for yeast?

Answer 27

sacchoromyces

Question 28

How does yeast get its food?

Answer 28

anaerobic respiration

Question 29

What is the equation for anaerobic respiration?

Answer 29

glucose —— 2 ethanol + 2 carbon dioxide

Question 30

How does yeast reproduce?

Answer 30

asexually - budding

Question 31

Explain budding.

Answer 31

1. parent cell divides by meiosis to form another nucleus
2. a bud forms on the cell and one nucleus enters the bud
3. eventually the bud will detatch from the cell to make 2 daughter cells

Question 32

What are 2 benefits and 2 disadvantages of fungi?

Answer 32

benefits - yeast produces alcohol, food

disadvantages - destroys material, causes disease