Question

The fungus in a lichen is which of the following? a. a basidiomycete b. an ascomycete c. a zygomycete d. an apicomplexan

Short answer

b. an ascomycete

Step-by-step solution

Understand the Question

Identify what is being asked: What type of fungus is found in a lichen? Remember that lichen is a symbiotic association between fungi and a photosynthetic partner, usually algae or cyanobacteria.

Review Fungal Groups

Review the characteristics of each fungal group provided in the options: basidiomycetes, ascomycetes, zygomycetes, and apicomplexans.

Identify Fungi Typically Found in Lichens

Recall that the majority of fungi forming lichens belong to the ascomycete group. Although some basidiomycetes may also form lichens, ascomycetes are far more common.

Eliminate Incorrect Answers

Remove options that do not fit: An apicomplexan is not a fungus, so it can be eliminated. Zygomycetes are rarely involved in lichen formations, and basidiomycetes are less common compared to ascomycetes.

Select the Correct Answer

Based on the information, the fungus in a lichen is usually an ascomycete.

Key concepts

lichens

Lichens are fascinating organisms that arise from a symbiotic relationship between fungi and photosynthetic partners, typically algae or cyanobacteria. These unique entities appear to be a single organism, but they are really a partnership. Lichens can survive in some of the harshest environments on Earth, including arctic tundras, deserts, and rocky coastlines. This resilience is largely due to the symbiotic relationship that allows them to combine the strengths of two different organisms. Lichens can grow on rock surfaces, tree bark, and even buildings, making them incredibly versatile in where they can live.

ascomycetes

Ascomycetes are a group of fungi that are most commonly found as the fungal component in lichen relationships. They are characterized by the production of spores in special sac-like structures called asci. Some well-known examples of ascomycetes include yeast and molds. The majority of fungal partners in lichens are ascomycetes, making them essential for the formation and survival of lichens. While some basidiomycetes can form lichens, ascomycetes are far more prevalent in these symbiotic associations.

fungal symbiosis

Fungal symbiosis is the mutualistic relationship between fungi and other organisms. In the case of lichens, this relationship involves a fungus and a photosynthetic partner. The fungus provides a protected environment and structure for the photosynthetic partner, which in turn supplies carbohydrates and other nutrients through photosynthesis. This mutually beneficial relationship allows lichens to thrive in environments that would be inhospitable to either partner on their own. Fungal symbiosis exemplifies how different species can collaborate for mutual benefit, enhancing survival and growth in challenging conditions.

photosynthetic partners

In lichens, the photosynthetic partners are usually algae or cyanobacteria. These partners are crucial for the survival of the lichen, as they produce food through photosynthesis. The carbohydrates produced by the photosynthetic partners are shared with the fungal component, providing the energy necessary for the lichen's survival. Cyanobacteria, a type of bacteria capable of photosynthesis, can also fix atmospheric nitrogen, adding another layer of nutritional support. This partnership allows lichens to colonize areas where nutrient availability is low, demonstrating the incredible adaptability and efficiency of these symbiotic relationships.