Free Biodiversity and Variety of Life MCQs with Answers

341. In the life cycle of Rhizopus, the hyphal tips after coming in contact with each are transformed into:

• A. Sporangia
• B. Conidiophores
• C. Sporangiophores
• D. Gametangia

Explanation: Answer is "Gametangia"Explanation: Means bodies containing gametes.Gametangia are specialized structures in fungi that produce gametes, which are haploid reproductive cells. Gametangia are typically found in fungi that reproduce sexually.There are two main types of gametangia: antheridia and archegonia. Antheridia produce male gametes, while archegonia produce female gametes.

342. In the life cycle of Black bread mold, gametangia after plasmogamy and karyogamy give rise to:

• A. Zygospore
• B. Basidiospore
• C. Ascospores
• D. Conidiophore

Explanation: Answer is "Zygospore"Explanation: It is a diploid resistant body which comes into being by fusion of two haploid nuclei of different strains.

343. In the life cycle of Rhizopus diploid spores are produced in:

• A. Asexual reproduction only
• B. Sexual reproduction only
• C. Both in sexual and asexual reproduction
• D. Both in fragmentation and budding

Explanation: Answer is "Sexual reproduction only"Explanation: Somatic body of fungus is haploid and it divides by mitosis to produce asexual spores.Diploid spores are produced in sexual reproduction in the life cycle of Rhizopus.Rhizopus is a heterothallic fungus, which means that it requires two different mating types in order to reproduce sexually.

344. Pick up the true choice with respect to the life cycle of Rhizopus:

• A. Haploid Zygospores mitosis ⎯⎯ →⎯ Haploid spores
• B. Diploid Zygospores mitosis ⎯⎯ →⎯ Diploid spores
• C. Diploid Zygospores meiosis ⎯⎯ →⎯ Haploid spores
• D. Diploid Zygospores meiosis ⎯⎯ →⎯ Diploid spores

Explanation: Answer is "Diploid zygospore ⎯⎯→Haploid spores"Explanation: Diploid zygospore undergoes meiosis to produce four haploid spores, two of plus strain and two of minus strain.Diploid zygospores are created when two haploid fungi fuse together. These zygospores then undergo meiosis, which splits the zygospore into four haploid spores. These spores are then dispersed and can grow into new haploid fungi.

345. Which one of the following phases of the life cycle of Rhizopus is delayed?

• A. Dikaryotic
• B. Heterokaryotic
• C. Diploid
• D. Meiosis

Explanation: Answer is "Meiosis"Explanation: Zygospore is a resistant dormant body which waits for arrival of favorable conditions and meiosis is delayed. This is because Rhizopus is a heterothallic fungus, which means that it requires two different mating types in order to reproduce sexually. The meiosis phase only occurs when two compatible mating types come together.

346. Without the activity of _ along with _ all the essential nutrients would soon become locked up in the mounds of dead animals and plants:

• A. Fungi, Saprobic bacteria
• B. Algae, Saprobic bacteria
• C. Fungi, Parasitic bacteria
• D. Algae, Parasitic bacteria

Explanation: Answer is "Fungi, saprobic bacteria"Explanation: Both of them are decomposers and recycler of nature.

347. Mycorrhizal fungi improve the growth of _ of all kinds of vascular plants through their association:

• A. 95%
• B. 90%
• C. 85%
• D. 80%

Explanation: Answer is "95%"Explanation: Symbiotic association is common in vascular plants.

348. _ growing on rocks breaks them, setting the stage for other organisms during ecological succession.

• A. Ectomycorrhizae
• B. Endomycorrhizae
• C. Bacteria
• D. Lichen

Explanation: Lichens growing on rocks breaks them, setting the stage for other organisms during the course of ecological succession.Lichens are a symbiotic relationship between a fungus and an alga. The fungus provides the alga with water and minerals, and the alga provides the fungus with food. Lichens are able to grow on bare rock because they secrete acids that break down the rock. This process is called lichenolysis.As lichens break down the rock, they create a small pocket of soil. This soil provides a habitat for other organisms, such as mosses and small plants. These organisms further break down the rock, creating more soil. This process continues until a mature ecosystem is established.Lichens are therefore important pioneer species in ecological succession. They are the first organisms to colonize bare rock, and they set the stage for the establishment of other organisms.

349. _ are very good bioindicators of air quality as they are very sensitive to pollution.

• A. Lichens
• B. Mycorrhizae
• C. Rhizopus
• D. Penicillium

Explanation: Answer is "Lichens"Explanation: They are sensitive to air pollution particularly to SO2 and start dieing immediately if air becomes polluted.Lichens are very good bioindicators of air quality as they are very sensitive to pollution. Lichens are organisms that are formed by a symbiotic relationship between a fungus and an alga. They are found in a variety of environments, but they are particularly sensitive to air pollution.

350. Bioremediation means:

• A. Degrading pollutants
• B. Removing pollutants
• C. Degrading or removing environmental poisons
• D. Degrading or removing environmental poisons or pollutants by organisms

Explanation: Answer is "Degrading or removing environmental poisons/pollutants by organisms"Explanation: Degrading or removing environmental poisons/pollutants by organisms is called bioremediation.