Fungi Bac 2100

Dimorphic fungi refers to fungi that have the ability to grow in two different forms, either as yeast or mold, depending on the temperature or environment. This means that these fungi can switch between a unicellular yeast form and a multicellular mold form. The term "dimorphic" is used to describe this ability to exist in two different morphological forms. Therefore, the correct answer for this question is "Dimorphic fungi."

Spores are reproductive structures produced by molds, yeast, and other organisms. They are capable of dispersing and germinating to form new individuals. In the context of the given options, spores are the most appropriate answer as they specifically relate to the reproduction of molds. Molds reproduce by producing spores, which are released into the environment and can then develop into new mold colonies under suitable conditions.

Hypae are threadlike branching tubules composed of fungal cells attached to end beds. They are a characteristic feature of fungi and play a crucial role in their growth and reproduction. Hypae are responsible for absorbing nutrients from the environment and can extend over long distances, allowing fungi to colonize and explore their surroundings. They can also form networks called mycelium, which is the main body of a fungus. Therefore, the given answer, Hypae, accurately describes the described structure.

Yeast is the correct answer because it is a type of fungi that can grow as single cells and reproduce by budding. When yeast cells do not separate after budding, they can form long chains known as pseudohyphae. This growth pattern is characteristic of yeast and distinguishes it from other types of fungi such as molds.

Saprophytes are fungi that obtain their energy by decomposing dead organic matter, such as soil and rotten vegetables. They play a crucial role in the ecosystem by breaking down and recycling nutrients from dead organisms, helping to maintain the balance of nutrients in the environment. This makes saprophytes an important part of the nutrient cycling process.

The given description of multicellular colonies composed of clumps of intertwined and branching hyphae best fits the characteristics of mold. Mold is a type of fungus that forms multicellular colonies made up of hyphae, which are thread-like structures. These colonies often appear as clumps and can have a branching pattern. Thus, mold is the correct answer in this case.

Keratinase is an enzyme that is present in cutaneous fungal infections. It is responsible for degrading the protein keratin, which is found in skin, hair, and nails. This degradation leads to the loss of hair and brittle nails commonly observed in fungal infections.

The correct answer lists the four levels of fungal infection, which are superficial, cutaneous, subcutaneous, and systemic. Superficial fungal infections affect only the skin, while cutaneous infections involve the skin, hair, and nails. Subcutaneous infections occur beneath the skin, and systemic infections spread through the bloodstream.

The two superficial fungal infections mentioned in the question are Pityriasis versicolor and Tinea nigra. Pityriasis versicolor is characterized by hyperpigmented patches that remain white after suntanning. Tinea nigra, on the other hand, presents as painless patches on the soles of hands and feet. Both of these infections can be treated with selenium sulfide.

The correct answer lists the five common cutaneous fungal infections. Tinea corporis is a fungal infection that appears as a ringworm under the skin. Tinea capitis is a fungal infection of the scalp characterized by scaly red regions and hair loss. Tinea pedis, also known as athlete's foot, occurs between the toes. Tinea cruris, or jock itch, causes a scratchy red area in the groin region. Tinea unguium affects the nails, causing them to become thickened, discolored, and brittle. Candida albicans is a yeast infection that can infect the mouth, groin, and vagina.

The two subcutaneous fungal infections mentioned in the given information are Sporothrix schenckii and Phialophora and cladosporium. Sporothrix schenckii causes sporotrichosis, which is a hazard for gardeners. It leads to the formation of subcutaneous nodules that become necrotic and ulcerative. Phialophora and cladosporium, on the other hand, are found in rotting wood and cause chromoblastomycosis. This infection results in the development of violent colored wart-like clusters of lesions that resemble cauliflower.

Histoplasma capsulatum is a dimorphic fungi that can be mistaken for tuberculosis (TB). It grows in a mycelial form with spores at 25 degrees on Sabouraud's agar. In humans, it grows as yeast. The infection occurs when the spores are inhaled and it is not transmitted person to person. The initial infection is localized in the lungs and can then spread to the bloodstream.

Cryptococcus neoformans is a type of yeast that is encapsulated and has a polysaccharide capsule. It is not dimorphic, meaning it does not have the ability to switch between different forms. The primary mode of transmission is through inhalation into the lungs. The major manifestation of infection is meningoencephalitis, which is an inflammation of the membranes surrounding the brain and spinal cord. This infection is most commonly seen in individuals who are immunocompromised, particularly those with AIDS.

Aspergillus flavus is a type of mold that can be found everywhere, as its spores are ubiquitous. Some individuals may develop type I hypersensitivity to this mold, meaning they have an allergic reaction when exposed to it. Additionally, Aspergillus flavus is known for producing Aflaxin toxin, which can contaminate peanuts, grains, and rice. This toxin can pose a health risk if consumed.