Tag: algae

Questions Related to algae

.......... is a source of additional fuel through carbohydrates.

biology micro - organism useful actions of algae introduction to algae algae

  1. Algae

  2. Bacteria

  3. Protozoa

  4. Fungi

Show answer
Correct Option: A
Explanation:
Algae are photosynthetic organisms related to plants that grow in water and produce energy from carbon dioxide and sunlight. Single-celled microalgae can be used to produce large amounts of fat, which can be converted into biodiesel, the most common form of biofuel. The carbohydrate content of algae can be fermented into bioethanol or butanol fuel.
So,  the correct option is 'algae'. 

Match column I with column II and select the correct option from the codes given below.

Column I Column II
A. Food (i)Brown algae
B. Agar (ii)Porphyra, Laminaria
C. Algin (iii) Geiidium, Graciiaria
D. Carrageenin  (iv)Red algae
biology micro - organism useful actions of algae introduction to algae algae

  1. A-(ii), B-(iii), C-(i), D-(iv)

  2. A-(ii), B-(iii), C-(iv), D-(i)

  3. A-(iii), B-(ii), C-(iv), D-(i)

  4. A-(iii), B-(ii), C-(i), D-(iv)

Show answer
Correct Option: A
Explanation:
  • Gelidium and Gracilaria are also types of red algae. Agar, a commercial product is also obtained from these algae are used to growing microbes and in preparation of ice cream and jellies.
  • Porphyra and Laminaria are some species of algae which are used as food.
  • Algin a colloidal substance derived from marine brown algae and used as emulsifiers or thickeners. It is used in many foods, such as ice cream, jam, yogurt, and some other dairy products.
  • Carrageenan is also used to thicken, emulsify and preserve foods and drinks. It comes from red algae. 
  • So, the correct answer is " A - (ii), B- (iii), C - (i),  D - (iv) ".

Algae have great economic importance to man because

biology micro - organism useful actions of algae introduction to algae algae

  1. They can be grown in tanks.

  2. They help to restore the fertility of the soil.

  3. Of their high protein content, some algae may be used as future food.

  4. Both B and C.

Show answer
Correct Option: D
Explanation:

Algae have great economic importance to man as it is a rich source of protein and some algae may be used as future food apart from this, it is also true that algae enriches the soil and can be a good source to make the soil fertile. Algae are being commercially used by man in many ways. Red algae is used to produce edible gelatin. Thus, the correct answer is option D.

Agar is obtained from which of the following alga?

biology micro - organism useful actions of algae introduction to algae algae

  1. $Sargassum$

  2. $Spirogyra$

  3. $Gelidium$

  4. $Chondrus$ $crispus$

Show answer
Correct Option: C
Explanation:

Agar is a jelly-like substance, obtained from algae and discovered in the late 1650s or early 1660s. Agar is derived from the polysaccharide agarose, which forms the supporting structure in the cell walls of certain species of algae, and which is released on boiling. These algae are known as agarophytes and belong to the Rhodophyta (red algae) phylum. Agar is actually the resulting mixture of two components: the linear polysaccharide agarose, and a heterogeneous mixture of smaller molecules called agaropectin.The gelling agent in agar is an unbranched polysaccharide obtained from the cell walls of some species of red algae, primarily from the genera Gelidium and Gracilaria. For commercial purposes, it is derived primarily from Gelidium amansii. In chemical terms, agar is a polymer made up of subunits of the sugar galactose.

An alga, very rich in protein, is

biology micro - organism useful actions of algae introduction to algae algae

  1. Nostoc

  2. Ulothrix

  3. Chlorella

  4. Spirogyra

Show answer
Correct Option: C
Explanation:

Chlorella is an alga with extremely important health benefits. It contains nearly 50% of proteins. It also contains certain essential amino acids. But because of its hard cell wall, it cannot be digested easily. So, it is available in the form of food supplements as tablets, capsules etc.

So, option C "Chlorella" is the correct answer.

Which type of algae are helpful in nitrogen economy?

biology micro - organism useful actions of algae introduction to algae algae

  1. Green algae

  2. Blue green algae

  3. Red algae

  4. Brown algae

Show answer
Correct Option: B
Explanation:

The majority of blue-greens are aerobic photoautotrophs, their life processes require only oxygen, light and inorganic substances. At the onset of nitrogen limitation, during bloom conditions, certain cells in Anabaena evolve into heterocysts, which convert nitrogen gas into ammonium, which is then distributed to the neighboring cells of a filament. In addition, blue-greens that form symbiotic (mutually beneficial) relationships with a wide range of other life forms, can convert nitrogen gas into ammonium.

Therefore, the correct answer is option B.

Algae are important to study because

biology micro - organism useful actions of algae introduction to algae algae

  1. They are good organisms to experiment with.

  2. They can be grown in large tank cultures.

  3. They may form important constituents of human food in future.

  4. They produce oxygen and organic acids.

Show answer
Correct Option: D
Explanation:

In addition to their ecological roles as oxygen producers and as the food base for almost all aquatic life, algae are economically important as a source of crude oil and as sources of food and a number of pharmaceutical and industrial products for humans. The taxonomy of algae is contentious and subject to rapid change as new molecular information is discovered. The study of algae is called phycology, and a person who studies algae is a phycologist.

People recovering from long illness are often advised to include the algae Spirulina in their diet because it

biology micro - organism useful actions of algae introduction to algae algae

  1. Makes the food easy to digest

  2. Is rich in proteins

  3. Has antibiotic properties

  4. Restores the intestinal microflora

Show answer
Correct Option: B
Explanation:

Some dieters say that blue green algae helps satisfy appetite and supplies good nutrition while dieting. Some dieters say that bluegreen algae Spirulina, a well-known example, is a group of 1,500 species of microscopic aquatic plants. The two most common species used for human consumption are Spirulina maxima and Spirulina platensis. Spirulina is particularly rich in protein and also contains carotenoids, vitamins, minerals, and essential fatty acids. Blue-green algae (Spirulina) is a concentrated source of nutrients compared to most foods, but it is expensive compared to other supplemental sources of protein, vitamins, and minerals.

Algae are useful because they

biology micro - organism useful actions of algae introduction to algae algae

  1. Purify the atmosphere

  2. Are large in number

  3. Are used in fermentation

  4. Are used to study respiration

Show answer
Correct Option: A
Explanation:

Algae is a collective term for all those chlorophyll bearing organisms which are thalloid. So, during photosynthesis by taking in ${CO _2}$ and giving out ${O _2}$ they purify the atmosphere

Which of the following blue-green algae helps in the formation of biofertilizers?

biology micro - organism useful actions of algae introduction to algae algae

  1. Anabaena

  2. Ocillataria

  3. Nostoc

  4. All of the above

Show answer
Correct Option: D
Explanation:
  • All of the above organisms are the genus of cyanobacteria which are used for fixing nitrogen in the nitrogen cycle.
  • So the correct answer is 'All of the above'.