Difference between Algae and Fungi, Practice Problems and FAQs

Pickles are a must have thing in Indian homes. We make pickles of different types of vegetables and fruits. We always keep the pickles in tight containers. Do you know the reason behind it? It is to avoid the air contact, which can spoil the pickles. Have you ever observed a spoiled pickle? If yes, then you might have seen some cottony white layer over it. What are those? They are fungi which formed because the pickle came in contact with the air and moist, which is suitable for a fungus to grow. This same group of organisms can be observed in a bread after the expiry date of it. We call this fungus, a bread mould.

If we observe this fungus under a microscope, we can see a thallus body with spore bearing structures in it. In the traditional system of classification of Kingdom Plantae, Eichler included fungi in the subkingdom Cryptogamae. In this subkingdom, the plants with hidden flowers and seeds are included. Along with algae, he included another plant called algae, which also has a thallus body type. Hence he made a subdivision called Thallophyta and included both fungi and algae in it, because thallus is a plant body without true stem, leaves or roots.

But apart from the thallophytic nature of their body, age and fungi have many differences. This made them to be in different Kingdoms in the classification of R. H. Whittaker. According to him, Fungi itself is a Kingdom and Algae is a group included in the Kingdom plantae. So we are going to discuss more about the differences between algae and fungi in this article.

Table of contents:

• Algae
• Fungi
• Difference between algae and fungi
• Practice Problems
• FAQs

Algae

The thallophytic plant which has the chlorophyll pigment and shows an autotrophic mode of nutrition are called algae. Hence algae can prepare their own food (photosynthetic). The number of algae that have been discovered is approximately 1 million species!

Fig: Algae

They are non vascular plants and have no true roots and true shoots (shoots without leaves). They were placed in the Plant Kingdom by Robert Whittaker. They also don't have flowers, fruits or seeds. Algae is considered as the first plant group that emerged from the unicellular aquatic organisms like cyanobacteria (blue green algae). Their size varies from unicellular body as in Chlamydomonas to giant kelps.

Fig: Chlamydomonas GIF: Kelps

Classification of algae

On the basis of their photosynthetic pigments, algae are classified into three groups and they are as follows:

• Rhodophyceae (Red algae) – primary pigments present are phycoerythrin and phycocyanin
• Phaeophyceae (Brown algae) – primary pigments present are fucoxanthin and violaxanthin
• Chlorophyceae (Green algae) – primary pigments present are chlorophyll a and b

Examples of algae

The examples of algae included in these three groups are as follows:

• Red algae : Polysiphonia, Gracilaria, Porphyra and Gelidium.

Fig: Examples of red algae

• Brown algae - Ectocarpus, Dictyota, Laminaria, Sargassum and Fucus.

Fig: Common examples of brown algae

• Green algae - Chlamydomonas, Volvox, Ulothrix, Spirogyra, Chara, and Chlorella.

Fig: Common examples of green algae

Fungi

The achlorophyllous (lack chlorophyll) thallophytes that show heterotrophic mode of nutrition are called fungi. Hence fungi depend on other organisms for food. R. H. Whittaker has considered fungi as a Kingdom in his five Kingdom classification.

GIF: Fungi

Fungi is also a large group of organisms with over 1,00,000 known species. Most of the fungi are terrestrial, but there are few that inhabit aquatic ecosystems. They generally choose warm and humid places to grow.

Fig: Different habitats of fungi

Fungus are generally multicellular. But yeast is a unicellular fungus. Multicellular fungi have long, tubular, filamentous structures called hyphae. Mass of hyphae is called mycelium. They are non vascular organisms that bear spores. Their cell wall is composed of fungal cellulose or chitin.

Fig: Hyphae in Fungi

Classification of fungi

On the basis of type of mycelium, type of sexual and asexual spores, Fungi are classified into four as follows:

• Phycomycetes – Mycelium is aseptate (without septa) and coenocytic (multinucleated protoplasm), they reproduce asexually by sporangiospores and sexually by zygospores or oospores.
• Ascomycetes – Mycelium is branched and septate, they reproduce vegetatively by budding and asexually by conidia (exogenously). Sexual reproduction is by ascospores.
• Basidiomycetes – Mycelium is branched and septate, asexual spores are generally not found, they generally propagate vegetatively by fragmentation. As sex organs are absent, sexual reproduction is performed by somatogamy.
• Deuteromycetes – Mycelium is septate and branched, they reproduce asexually by conidia and sexual reproduction is absent.

Fig: Classification of fungi

Examples of fungi

The major examples included in different fungal groups are as follows:

• Phycomycetes – Phytophthora infestans, Albugo candida, Rhizopus (Bread mould), Mucor etc.

Fig: Examples of Phycomycetes

• Ascomycetes – Penicillium, Saccharomyces, Aspergillus, Claviceps, Morchella, Neurospora, morels.

Fig: Examples of Ascomycetes

• Basidiomycetes – Agaricus (mushroom), Bracket (Shelf) fungi, Puffballs, Ustilago (smut fungi), Puccinia (Rust fungi).
• Deuteromycetes – Trichoderma, Colletotrichum etc.

Difference between algae and fungi

The major differences between algae and fungi are as follows:

Practice Problems

1. Algae are classified into Chlorophyceae, Phaeophyceae and Rhodophyceae on the basis of their

1. Stored food materials
2. Photosynthetic pigments
3. Thallus organisation
4. Habitat

Solution: The thallophytes which are composed of chlorophyll pigment and show an autotrophic mode of nutrition are called algae. Hence algae can prepare their own food (photosynthetic). On the basis of their photosynthetic pigments, algae are classified into three groups and they are Chlorophyceae, Phaeophyceae and Rhodophyceae. Chlorophyceae is also called green algae and it has chlorophyll a and b as photosynthetic pigments. Phaeophyceae is also called brown algae and the photosynthetic pigments found in them are fucoxanthin and violaxanthin. Rhodophyceae or the red algae has phycoerythrin and phycocyanin as pigments. Hence the correct option is b.

2. In which of the following fungi, sexual reproduction is absent?

1. Phycomycetes
2. Ascomycetes
3. Basidiomycetes
4. Deuteromycetes

Solution: In Phycomycetes, the mycelium is aseptate (without septa) and coenocytic (multinucleated protoplasm), they reproduce asexually by sporangiospores and sexually by zygospores or oospores. In ascomycetes, the mycelium is branched and septate, they reproduce vegetatively by budding and asexually by conidia (exogenously). Sexual reproduction is by ascospores. In Basidiomycetes, the mycelium is branched and septate, asexual spores are generally not found, they generally propagate vegetatively by fragmentation. As sex organs are absent, sexual reproduction is performed by somatogamy. In Deuteromycetes the mycelium is septate and branched, they reproduce asexually by conidia and sexual reproduction is absent. Hence the correct option is d.

3. Choose the wrong statement about the algae from the following.

1. They are mostly aquatic organisms
2. Cell wall is made up of cellulose
3. Plant body is called mycelium
4. Starch is mostly seen as stored food material

Solution: The thallophytes which are composed of chlorophyll pigment and show an autotrophic mode of nutrition are called algae. Hence algae can prepare their own food (photosynthetic). They are non vascular plants and have no true roots and true shoots (shoots without leaves). Hence the plant body of algae is called thallus. They were placed in the Plant Kingdom by Robert Whittaker. They also don't have flowers, fruits or seeds. Fungus are generally multicellular. But yeast is a unicellular fungus. Multicellular fungi have long, tubular, filamentous structures called hyphae. Mass of hyphae is called mycelium. Hence the correct option is c.

4. Which of the following options has the examples of a fungus?

1. Albugo, Rhizopus, Mucor
2. Agaricus, Ustilago, Chlorella
3. Volvox, Ulothrix, Spirogyra
4. Trichoderma, Colletotrichum, Selaginella

Solution: Phytophthora infestans, Albugo candida, Rhizopus (Bread mould), Mucor etc. are the major examples included in the group Phycomycetes. The examples of Ascomycetes are Penicillium, Saccharomyces, Aspergillus, Claviceps, Morchella, Neurospora, morels etc. Basidiomycetes include Agaricus (mushroom), Bracket (Shelf) fungi, Puffballs, Ustilago (smut fungi), Puccinia (Rust fungi) etc. Examples of Deuteromycetes are Trichoderma, Colletotrichum etc. Chlorella, Spirogyra, Selaginella are examples of algae. Hence the correct option is a.

FAQs

1. What are lichens?
Answer: Lichens are the symbiotic or mutualistic relationship between the fungi and algae or cyanobacteria. The algae prepares food and the fungi provides protection to algae. The algal partner is called phycobiont and the fungal partner is called mycobiont.

Fig: Lichen

2. Which algae and fungi can be used as food?
Answer: The species of algae used as food materials are Porphyra and Sargassum. Agar is a product derived from algae like Gracilaria and Gelidium. Agar is used in the preparation of chocolates, jellies and ice-creams. Species like Chlorella and Spirulina are rich in proteins and used as food supplements.

The most common fungi which are used as food are the mushrooms. Yeast is an important factor in the preparation of bread, alcoholic and non-alcoholic beverages and probiotics.

3. What is a mixotrophic nutrition?
Answer: Mixotrophic nutrition can be observed in some algae like Chlamydomonas. It is the utilisation of both inorganic and exogenous organic sources to fulfil the nutritional needs.

4. Which fungus has the name ‘fungi imperfecti’?
Answer: The fungus included in the group Deuteromycetes are called fungi imperfecti. The reason for this is the absence of sexual reproduction in these groups. When the Deuteromycetes which have the sexual forms were found, they have moved to either ascomycetes or basidiomycetes. They move on the basis of spores they produce.

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