1. Fern

2. Lichen

3. Moss

4. Mushroom

Select the correct answer using the code given below.

(a) 1 and 4 Only

(b) 2 Only

(c) 2 and 3

(d) 1, 3 and 4

4. Ans: c

Explanation:

Algae, lichens, liverworts, and moss are often in nature found growing in damp or shady places in the garden on plants, soil and hard surfaces, they even can grow without soil. 

Lichens: 

Lichens are a complex life form that is a symbiotic partnership of two separate organisms, a fungus and an alga. The dominant partner is the fungus, which gives the lichen the majority of its characteristics, from its thallus shape to its fruiting bodies. The alga can be either a green alga or a blue-green alga, otherwise known as cyanobacteria. Many lichens will have both types of algae. 

What are fungi?

• Fungi are a diverse group of organisms that are in their own kingdom (Fungi), separate from plants. Fungi do not contain chlorophyll or any other means of producing their own food so they rely on other organisms for nutrition. Fungi are widely known for their role in the decomposition of organic matter. They are also necessary for the survival of the ecosystem around them, such as partnering with plants and trees for nutrients and survival.

What are algae?

• Algae are in another kingdom (Protista) separate from plants and fungi. There are several types of algae: green, brown, red, gold. They can survive in salt water and in freshwater on their own, and in any environment when part of a lichen relationship.
• Although cyanobacteria are called blue-green algae, they are actually bacteria, and are part of the bacteria kingdom, Monera. The “blue” in the common name refers to the fact that they need to live in water, and “green algae” refers to their photosynthetic abilities, like green algae.

Lichens, do not have any roots, stems or leaves and their chloroplasts are contained only in the algae on the top surface of the lichen.

Important function of lichens is that they provide a mode of survival in harsh environments, 

lichens directly benefit humans is through their ability to absorb everything in their atmosphere, especially pollutants. Lichens can provide us with valuable information about the environment around us. Any heavy metals or carbon or sulfur or other pollutants in the atmosphere are absorbed into the lichen thallus.

Lichens can be seen hanging off of trees or clinging to rocks. 

Mosses:   

• Mosses are very primitive, the ancestors of the trees , they have plant-like structures that look like and function like leaves, stems and roots. They have chloroplasts throughout their entire bodies and can photosynthesize from all sides of their structures.
• Mosses along with lichens are the first organisms to colonise rocks and hence, are of great ecological importance. They decompose rocks making the substrate suitable for the growth of higher plants

Ferns

• Ferns are plants that do not have flowers. Ferns generally reproduce by producing spores. Similar to flowering plants, ferns have roots, stems and leaves. 
• However, unlike flowering plants, ferns do not have flowers or seeds; instead, they usually reproduce sexually by tiny spores or sometimes can reproduce vegetatively
• The ferns are an ancient lineage of plants, dating back to at least the Devonian. They include three living groups — Marattiales, Ophioglossales, and leptosporangiate ferns — as well as a couple of extinct groups.  
• Ferns are plants that do not have flowers. Ferns generally reproduce by producing spores. Similar to flowering plants, ferns have roots, stems and leaves. However, unlike flowering plants, ferns do not have flowers or seeds; instead, they usually reproduce sexually by tiny spores or sometimes can reproduce vegetatively.

Mushrooms

• Mushrooms are the reproductive structures (fruiting bodies) of organisms that otherwise live as microscopic threads of cells in various substrates such as soil, wood, or living tissues of associated plants.  
• The threadlike cells (hyphae) in mass are referred to as the mycelium. Fruiting bodies are produced from the mycelium to carry out sexual reproduction-the formation and release of spores.
• Spores allow fungi to disperse and survive until conditions are right for germination and establishing a new colony. 
• Fungi generally are classified as pathogens, saprobes, and mutualists .
• Pathogens attack and often kill living tissues and may kill the host organism .
• A true saprobe lives only on dead organic matter such as heartwood of standing trees, woody debris, or fallen leaves .
• saprobes decompose the organic layers of the forest floor: stems, branches, and leaves. 
• . The genera Aleuria, Clitocybe, Collybia, Marasmius, Morchella, Mycena, Naemataloma, Phoiiota, and Scutellinia represent some of the variety of saprobes
• Fungi interact with many soil organisms, including bacteria, other fungi, nematodes, microarthropods, and insects. They serve as prey to and predators of organisms in these group .
•  A large portion of the total forest ecosystem biomass resides in the living fungi, which rapidly die and recycle their nutrients to the soil . This great fungal component not only recycles nutrients but also captures significant amounts of forest nutrients, which reduces leaching loss from the system. 
• Mutuatlism 
• Third major group of fungi, the mutuatists, live in intimate association with plants and interact in various ways that, in this instance, benefit both partners, hence, mutuatistic symbiosis. Among fungi, the predominant mutualistic symbiosis in forests takes place with plant roots producing structures called mycorrhizae. 
• Mycorrhiza literally translates as “fungus-root” 
• The mycorrhizal fungus basically serves as an extension of the plant root system, exploring soil far beyond the reach of the roots and transporting water and nutrients to the roots. The uptake of phosphorus and nitrogen are especially critical functions of mycorrhizal fungi, which can release bound forms of these nutrients otherwise unavailable to the roots. In return, the plant is the primary energy source for the fungus, providing simple sugars and vitamins produced in photosynthesis and transported to the roots and then the fungus.
• Mycorrhizal fungi are less capable of decomposing complex carbon molecules from organic debris than are saprobes. This dependency of fungi on their hosts for growth and survival is critical to mushroom production by mycorrhizal fungi.

Hence, option c is correct.

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