Question 1

The filaments that MOST fungi produce to absorb nutrients are called:

Accepted Answer

Fungi absorb nutrients through hyphae, which are thin, filamentous structures that make up the body of a fungus. Root hairs are specialized cells of plants that absorb water and nutrients from the soil. Ectomycorrhizae are a type of mutualistic association between fungi and the roots of certain plants. Chitins are a type of complex carbohydrate that make up the cell walls of fungi and some other organisms. Fruiting bodies are structures that some fungi produce to disperse spores, but they are not involved in nutrient absorption.

Question 2

Which of the following BEST describes the role of fungi in an ecosystem?

Accepted Answer

Fungi play a crucial role in ecosystems as decomposers, breaking down dead and decaying organic matter and recycling nutrients back into the ecosystem. They also form mutualistic relationships with plants, helping them absorb nutrients from the soil. However, fungi are not autotrophs, herbivores, carnivores, or producers, as they do not produce their own food or consume other organisms.

Question 3

Fungi include:

Accepted Answer

Fungi can be yeasts, decomposers, pathogens, and smuts, among other types. Therefore, all of the choices are correct.

Question 4

Imagine that fungal hyphae were as thick as a human hair. How might this increase in thickness affect the ecological role of fungi?

Accepted Answer

Fungal hyphae with a decreased surface area to volume ratio due to increased thickness would be less efficient in nutrient absorption and enzyme secretion, leading to slower decomposition rates.

Question 5

The network of branching filaments that form the main body of a multicellular fungus is the:

Accepted Answer

The mycelium is the network of branching filaments that form the main body of a multicellular fungus. The hypha is a single filament that makes up the mycelium. The fruiting body is the visible reproductive structure of the fungus, and the spore is a reproductive cell that is produced by the fruiting body. Rhizoids are root-like structures that are found in some fungi and plant-like organisms.

Question 6

Which of the following statements MOST accurately describes the anatomy of a multicellular fungus?

Accepted Answer

A multicellular fungus is composed of numerous hyphae that make up a mycelium. The mycelium is the vegetative part of the fungus and is responsible for absorbing nutrients from the environment. The hyphae are long, branching filaments that grow from the fungal spores and can spread out over large areas. The mycelium is often hidden underground or within the substrate on which the fungus grows.

Question 7

The fungi are most closely related to:

Accepted Answer

Fungi are most closely related to arthropods because both produce chitin, a structural polysaccharide found in fungal cell walls and arthropod exoskeletons.

Question 8

Which of the following statements comparing fungal and animal nutrition is CORRECT?

Accepted Answer

Fungi secrete digestive enzymes into their food, breaking it down externally before absorbing the nutrients, while animals generally ingest their food and digest it internally.

Question 9

The numerous thin filaments that make up the body of a multicellular fungus are the:

Accepted Answer

The thin filaments that make up the body of a multicellular fungus are called hyphae. Mycelia are the branching networks of hyphae that form the body of a fungus. Fruiting bodies are the reproductive structures of fungi and spores are the reproductive cells. Rhizoids are specialized hyphae that anchor some fungi to their substrates.

Question 10

A researcher has been studying lichens in his hometown. Since he began his study, he has noticed several lichens dying in the vicinity of a new factory. What is MOST likely causing the decrease in lichen populations?

Accepted Answer

The most likely cause of the decrease in lichen populations is an increase in industrial pollutants in the area. Lichens are sensitive to pollution and can be used as indicators of air quality. The emissions from the factory may be depositing harmful chemicals onto the lichens, causing their death.

Question 11

The _____ is a web of hyphae produced by a fungus in response to encountering a food source.

Accepted Answer

The answer of The _____ is a web of hyphae...

Question 12

Lichens are able to obtain nutrients from their environment by:

Accepted Answer

Lichens secrete organic acids that help break down minerals in their environment, releasing nutrients that they can absorb.

Question 13

Basidiomycetes are the only fungal group that produces lignin peroxidases, which are chemicals that can break down lignin and lignified tissues. Basidiomycetes growing within a fallen log would get less nutrition than ascomycetes because more of the cellulose in the log would be available to be broken down and absorbed.

Accepted Answer

Basidiomycetes are known for their ability to break down lignin and lignified tissues, which actually allows them to access the cellulose more efficiently than many other fungi, including ascomycetes. This ability to degrade lignin gives them an advantage in decomposing wood and accessing the cellulose for nutrition.

Question 14

Which of the compounds found in wood are difficult to degrade (or break apart)?

Accepted Answer

The answer of Which of the compounds found in wood...

Question 15

Fungi feed through extracellular digestion and then absorption. How would the rates of decomposition of detritus be altered if fungicide (something that kills fungi) were sprayed on the forest floor?

Accepted Answer

Fungi play a crucial role in the decomposition of detritus, so if fungicide were sprayed on the forest floor, the fungi would be destroyed and their ability to decompose detritus would be significantly reduced. Bacteria may also contribute to decomposition, but they are not as effective at breaking down complex organic matter as fungi are. While fungi do have hyphae above ground, they are still vulnerable to fungicide if it is sprayed on their substrate or if they have direct contact with it. Therefore, D is not a viable option.

Question 16

What is the advantage of a fungal body being composed of numerous thin hyphae instead of one or two very thick hyphae?

Accepted Answer

A greater surface area allows for more efficient absorption of nutrients, as there is more opportunity for contact with the surrounding environment.

Question 17

Fungal cell walls are composed of what material?

Accepted Answer

Fungal cell walls are mainly composed of chitin, a complex polysaccharide made up of repeating units of N-acetylglucosamine.

Question 18

The development of septa in the hyphae of fungi was an important evolutionary step. Why?

Accepted Answer

The development of septa in the hyphae of fungi allows for the sealing of septal pores to prevent the cytoplasm from leaking out if a hypha is damaged. This is important for the survival of the fungus.

Question 19

Fungi can cause various diseases, but they can also be beneficial to humans. Which of the following result from fungi?

Accepted Answer

Fungi are responsible for smut or rust crop infections (A), they are used in the fermentation process to make leavened bread (B), soy sauce (C), and some soft cheeses (E). They can also cause certain skin infections (D).

Question 20

Which of the following materials can serve as food sources for fungi?

Accepted Answer

Fungi are decomposers that can break down a wide variety of organic materials, including elephant dung, leaf matter, animal carcasses, fallen trees, and fruit. They play a crucial role in nutrient cycling by decomposing dead organic matter.

Quiz 34: Fungi: Structure, Function, and Diversity