Exam 2: Lecture 15 (Chapter 31)

Question 1

What are some characteristics of Fungi

Answer 1

1. Eukaryotic heterotrophs that feed through absorption
2. Cell walls composed of Chitin
3. Multicellular organisms dispersed by spores
4. Bodies composed of Hyphae

Question 2

What are Hyphae

Answer 2

Hyphae are the networks of tiny filaments that form fungal bodies

Question 3

Hyphae are ______, made of a hard wall of _______, and only grow at the ________.

Answer 3

Tubular, chitin, and grow at the tips

Question 4

Hyphae are divided by cross-walls called _______, that have large pores enabling ________ _______ ________.

Answer 4

Septa, cell-to-cell movement of organelles

Question 5

What are the types of fungi and their feeding

Answer 5

ALL FUNGI ARE HETEROTROPHIC
Sparophytes/Saprobes: Feed on dead tissues and organic waste

Symbionts: Mutually beneficial relationship between fungus and other organisms

Parasites: feed on living tissue of a host

Question 6

What are the steps of absorptive feeding

Answer 6

1. Hyphal tips release enzymes
2. Enzymes break down substrate
3. Product diffuses back into hyphae

Question 7

Fungi use _______ to communicate their mating typ

Answer 7

Pheromones

Question 8

Define Heterokaryons, dikaryotic mycelium, and karyogamy

Answer 8

Heterokaryons: Cells with two or more genetically distinct nuclei within the same cytoplasm.
Dikaryotic mycelium: Fungal hyphae with two distinct nuclei per cell, typically seen in fungi before karyogamy.
Karyogamy: The fusion of two nuclei in a cell, leading to the formation of a diploid nucleus.

Question 9

What are the Phylum Chytridiomycota

Answer 9

Simple fungi found in freshwater, marine, and terrestrial habitats that have flagellated and motile spores called Zoospores
(roles: Decomposers, mutalists, parasites of algae)

Question 10

What are the Phylum Mucoromycota

Answer 10

They are fast-growing molds, parasites, and symbionts that reproduce asexually through spores, and sexually through zygosporangium.

Question 11

What are the Phylum Ascomycota

Answer 11

Most common fungi (75%), also called the sac fungi, because they produce sexual spores in “Asci”

Question 12

What is the Asci

Answer 12

Sac-like structures found in Ascomycota fungi, where sexual spores, called ascospores, are produced and stored.

Question 13

________ are a part of the Ascomycetes phyla and mainly ferment carbohydrates

Answer 13

Yeasts

Question 14

How do Basidiomycetes reproduce

Answer 14

They reproduce sexually; 4 basidiospores (n) are produced on a basidium and spread around through spores.

Question 15

What are some of the ecological roles of fungi

Answer 15

1. Decomposers (break down cellulose and lignin)
2. Act as mutalists
3. Act as pathogens

Question 16

The _________ fungi has formed a __________ relationship with plants, and is found on the roots of 90% of vascular plants.

Answer 16

Mycorrhizae, mutualistic

Question 17

How does Mycorrhizae fungi help plants

Answer 17

The fungi improve the plants ability to absorb water and phosphorous, and receives photosynthetic sugars from the plant in return