Bio 220: Lecture 18 - Fungi (Continued)

Front 1

Fungi can produce reproductive hyphae which ...

Back 1

project above their growth substrate.

Front 2

Reproductive hyphae can produce either ___ or ___ spores.

Back 2

asexual or sexual

Front 3

Fungal spores are both ___ and ___

Back 3

resistant and reproductive cells.

Front 4

Spores can land back on the substrate and form ___.

Back 4

new hyphae

Front 5

True/False: Asexual spores produce new hyphae with the same genetics as the strain from which they came.

Back 5

True

Front 6

True/False: Sexual spores will form hyphae with the mixed genetics from two different strains of the mold.

Back 6

True

Front 7

What are some asexual spore type?

Back 7

1. Blastospores
2. Chlamydospores
3. Arthrospores
4. Sporangiospores
5. Conidiospores

Front 8

True/False: Asexual spores will produce new hyphae with different genetics from the strain they came from.

Back 8

False

Front 9

What are blastospores?

Back 9

there are the same as the buds found on yeast cells

Front 10

What are clamydospores?

Back 10

thick-walled spores that are highly resistant to adverse conditions

Front 11

True/False: Sexual spores will form hyphae with the same genetics from two different strains of mold.

Back 11

False

Front 12

What are arthrospores?

Back 12

described as cast or barrel or cylindrically shaped. They are formed by the disjointing or fragmentation of hyphal cells.

Front 13

What are sporangiospores?

Back 13

spores form within sacs at the end of hyphae
Example: Rhizopus

Front 14

What are conidiospores?

Back 14

spores formed by extrusion of single cells from specialized area of hyphae. The spores are not enclosed in a sac.
Examples: Penicillium (branching pattern) and Aspergillus (linear pattern).

Front 15

What are some examples of sexual spore types?

Back 15

1. zygospores
2. ascospores
3. basidiospores

Front 16

What are zygospores?

Back 16

large spores encased in a thick wall.
Example: Rhizopopus

Front 17

What are ascospores?

Back 17

spores within a "pea pod like structure known as an ascus.
Example: Penicillium and Aspergillus

Front 18

What are basidiospores?

Back 18

are found amongst the gills of the fleshy mushrooms

Front 19

Fungi imperfecti

Back 19

this is a special category of fungi where sexual reproduction methods have not yet been observed. This fungi imperfecti category should be thought of as a temporary or holding category. At one time both Aspergillus and Penicillium were placed here. It is now known that these two genera produce sexual spores known as ascospores.

Front 20

define: symbiosis

Back 20

the living together of two different organisms or populations. There are several kinds of symbioses in the living world.
• two life forms coexist in the lichen, a fungus and an alga. Both life forms benefit from this coexistence.
Therefore this represents a mutualistic symbiotic relationship.

Front 21

What is an example of a mutualistic symbiotic relationship?

Back 21

lichen, where two life forms coexists, a fungus and an alga

Front 22

What is a mycorrhiza?

Back 22

a fungus growing in symbiosis with plant roots

Front 23

What is an example of a mycorrhiza?

Back 23

truffles
• Truffles (mostly from the genus Tuber) are a mass of mycelia and ascospores wrapped around the roots of the tree.
• they are odiferous and is a food delicacy.
• Truffles benefit by gaining access to the tree's carbohydrates while the tree benefits from water and mineral content delivered by the truffles.

Front 24

How are mycoses categorized?

Back 24

by the level of tissue involvement in the host

Front 25

What are the four categories of mycoses?

Back 25

1. cutaneous mycoses
2. subcutaneous mycoses
3. superficial mycoses
4. systemic mycoses

Front 26

What are superficial mycoses?

Back 26

only the outer layers of the hair and skin are affected.
• Generally these are quite mild and are mainly of cosmetic interest.
• Tinea versacolor (disease not agent) causes a mild discoloration and a brownish scaling on the trunk, neck or arms.
• Tinea nigra can present as black spots upon the palms of the hands
• Tinea alba will produce white area upon the skin

Front 27

What are cutaneous mycoses?

Back 27

these infect the epidermis, hair and nails. These fungal organisms secrete the enzyme keratinase which is used to breakdown the protein keratin. Since keratin is required as a nitrogen source, these organisms are restricted to growing in the epidermis and areas where keratin is found.
• There are several tineas (ringworm) infections associated with cutaneous mycotic infections.
• Exampls are Tinea pedic, Tinea corporis, Tinea barbae, Tinea cruris
• Three genera associated with cutaneous mycoses are Microsporum, Epidermophyton and Trichophyton.

Front 28

What is Tinea pedis?

Back 28

ringworm of the foot and also known as "Athletes Foot"
• an example of a cutaneous mycoses

Front 29

What is Tinea corporis?

Back 29

ringworm of the body
• an example of a cutaneous mycoses

Front 30

What is Tinea barbae?

Back 30

ringworm of the beard
• an example of a cutaneous mycoses

Front 31

What is Tinea cruris?

Back 31

ringworm of the groin area, also known as "jock itch"
• an example of a cutaneous mycoses

Front 32

What are the three genera associated with cutaneous mycoses?

Back 32

Microsporium, Epidermophyton, and Trichophyton

Front 33

Most fungi are ___ pathogens.

Back 33

opportunistic

Front 34

Fungi are generally part of the normal flora and we only see them as ___ under certain circumstances.

Back 34

mild pathogens

Front 35

Who has an increased risk of serious infections with opportunistic pathogens?

Back 35

Debilitated individuals, trauma victims, those using broad spectrum antibiotics, those using immunospressive agents (corticosteroids), drug addicts, obese individuals, alcoholics, diabetics, undernourished, and those under stress are al subject to increased risk of opportunistic pathogens.

Front 36

True/False: Fungal organisms are prokaryotes.

Back 36

false

Front 37

True/False: Fungal organisms are eukaryotes.

Back 37

true

Front 38

Our medicines for treatment are more likely to be ___ on our own eukaryotic cells.

Back 38

toxic

Front 39

What are subcutaneous mycoses?

Back 39

most are caused by the yeast called Candida albicans. Candida albicans is typically part of our own normal flora. This infection can involve the skin and the subcutaneous tissues without going any deeper. The disease is called candidiasis or moniliasis. It is also called "thrush" and can be seen in children and older adults as white patches on the inside of the mouth or tongue. This infection can also be seen in warm moist environments where irritation is oftentimes a factor.
• The axilla, intergluteal folds, groin area, inframammary folds and belt line are common areas of infection.
• AIDS patients will experience Candida infections as their immune systems are compromised. Candida can work its way into the blood stream and go systemic.
• It can infect the heart valves and cause a candidal endocarditis.

Front 40

What are systemic mycoses?

Back 40

fungal organisms that have spread throughout the body and have invaded deeper tissues. These are rare infections but can be very serious and difficult to treat.
• The yeast-like organisms that cause these dimorphic (two appearances).
• At 37 degrees C. they are yeast-like.
• At 25 degrees C. they grow hypha, and are mold-like.