Biological Classification – NEET Biology MCQs (Part 8)

Correct Answer: B

Fungi constitute a unique kingdom of organisms that are heterotrophic in nature. Unlike plants, fungi cannot prepare their own food because they lack chlorophyll and do not perform photosynthesis. Instead, they obtain nutrients by absorbing organic substances from their surroundings. Some fungi live as decomposers on dead organic matter, while others may live as parasites or in symbiotic relationships with other organisms.

Correct Answer: A

Fungi exhibit a wide diversity in both morphology and habitat. They range from microscopic unicellular forms like yeast to large multicellular organisms such as mushrooms. Fungi can be found in a variety of habitats including soil, water, decaying organic matter, plants and animals. This diversity in structure and environment makes fungi an important and varied group of organisms in nature.

Correct Answer: B

Fungi commonly grow on moist bread and rotten fruits because these materials provide suitable conditions such as moisture and organic nutrients. Fungi are heterotrophic organisms that obtain their food from decaying organic matter. The presence of moisture and nutrients allows fungal spores to germinate and grow rapidly, forming visible mould on bread and fruits.

Correct Answer: C

Mushrooms and toadstools are examples of fungi. They belong to Kingdom Fungi because they are heterotrophic organisms that absorb nutrients from organic matter. Unlike plants, fungi do not contain chlorophyll and cannot perform photosynthesis. Mushrooms are often seen growing on soil or decaying organic matter, where they play an important role as decomposers in ecosystems.

Correct Answer: B

The term toadstool is commonly used for poisonous or inedible mushrooms. Although both mushrooms and toadstools belong to Kingdom Fungi, the word toadstool is usually used for fungi that are toxic or unsafe to eat. Some species such as Amanita are well-known poisonous toadstools.

Correct Answer: C

White spots on mustard leaves are caused by a parasitic fungus. This fungal infection commonly results in a disease known as white rust of mustard. The fungus grows on the plant tissues and forms white blister-like spots on the leaves. As a parasite, the fungus obtains nutrients from the host plant, which can damage the plant and affect crop yield.

Correct Answer: B

Most fungi are multicellular, but some fungi are unicellular. Yeast is a common example of a unicellular fungus. It consists of a single cell and reproduces mainly by budding. Yeast is widely used in baking and fermentation processes such as bread making and alcohol production. Because it is a single-celled organism, it is classified as a unicellular fungus.

Correct Answer: B

Yeast is a unicellular fungus widely used in the preparation of bread and beer. During fermentation, yeast converts sugars into alcohol and carbon dioxide. In bread making, the carbon dioxide produced causes the dough to rise and become soft and fluffy. In beer production, the alcohol produced during fermentation forms the main alcoholic content of the beverage.

Correct Answer: B

Although many fungi are useful as decomposers or in food production, some fungi are harmful and cause diseases in plants and animals. These fungi live as parasites and obtain nutrients from the host organism. Plant diseases such as rusts and smuts are caused by fungi, while some fungal infections also affect animals and humans.

Correct Answer: B

Wheat rust is a serious plant disease caused by the parasitic fungus Puccinia. This fungus infects wheat plants and produces rust-colored pustules on leaves and stems. The infection reduces photosynthesis and weakens the plant, leading to decreased crop yield. Puccinia is therefore considered an important example of a plant pathogenic fungus affecting agricultural crops.

Correct Answer: B

Penicillium is a fungus that produces the antibiotic penicillin. This antibiotic was discovered by Alexander Fleming in 1928 and is widely used to treat bacterial infections. Penicillin works by inhibiting the growth of bacteria, making it an important medicine in modern healthcare. Because of this property, Penicillium is considered a very useful fungus.

Correct Answer: B

Fungi are described as cosmopolitan organisms because they are widely distributed in nature. They can be found in many different environments such as air, water and soil. In addition, fungi grow on plants, animals and decaying organic matter. This wide distribution allows them to play important roles in ecosystems, especially as decomposers that break down dead organic material.

Correct Answer: B

Fungi usually grow best in warm and humid environments. Moisture and moderate temperatures provide suitable conditions for fungal spores to germinate and grow. This is why fungi are commonly seen on moist bread, rotten fruits and damp organic matter. Such environments supply the nutrients and moisture necessary for their growth and reproduction.

Correct Answer: B

Food is stored in a refrigerator to slow down the growth of microorganisms such as bacteria and fungi. These microorganisms multiply rapidly at warm temperatures and cause food to spoil. Refrigeration lowers the temperature, which slows down microbial growth and metabolic activity. As a result, food remains fresh for a longer time and the chances of bacterial or fungal infection are reduced.

Correct Answer: B

Yeasts are a type of fungus that exist as single-celled organisms, unlike most fungi which are multicellular. They reproduce mainly by budding and are widely used in fermentation processes such as bread making and alcohol production. Because they consist of only one cell, yeasts are classified as unicellular fungi.

Correct Answer: B

Most fungi are multicellular and filamentous in structure. They are composed of long thread-like structures called hyphae that form a network known as mycelium. However, yeast is an exception because it is unicellular. Therefore, while most fungi are filamentous, yeast represents a single-celled form of fungi.

Correct Answer: B

The body of most fungi is made up of long, thin, thread-like structures known as hyphae. These hyphae grow and branch repeatedly to form a network called mycelium. The mycelium spreads over the surface or inside the substrate from which the fungus absorbs nutrients. This filamentous structure helps fungi obtain food efficiently from their surroundings.

Correct Answer: A

In fungi, the body is composed of long, thread-like structures called hyphae. These hyphae grow, branch and interconnect to form a dense network. This interconnected network of hyphae is called mycelium. The mycelium spreads through the substrate and absorbs nutrients from the surrounding environment, helping the fungus grow and survive.

Correct Answer: A

Most fungi are filamentous organisms. Their body is made up of long, slender, thread-like structures called hyphae. These hyphae grow and branch repeatedly to form a complex network known as mycelium. The mycelium spreads through the substrate and absorbs nutrients from the surroundings, which helps the fungus grow and survive.

Correct Answer: B

In some fungi, the hyphae do not have cross walls (septa). These hyphae form long continuous tubes containing cytoplasm with many nuclei. Such hyphae are called coenocytic hyphae. Because there are no septa dividing the cytoplasm into separate cells, the cytoplasm remains multinucleate throughout the length of the hypha.

Correct Answer: B

In many fungi, the hyphae are divided by cross walls called septa. These septa separate the hypha into distinct cells. Such hyphae are known as septate hyphae. Each compartment usually contains one or more nuclei. This structure helps in better organization and regulation within the fungal body.

Correct Answer: B

The cell walls of fungi are mainly made up of chitin and other polysaccharides. Chitin is a strong structural carbohydrate that provides rigidity and protection to fungal cells. This composition is different from plant cell walls, which are mainly made of cellulose, and bacterial cell walls, which contain peptidoglycan.