Tag: archaebacteria

Questions Related to archaebacteria

Choose the correct answers from the alternatives given.
Which of the following is mismatched?

botany the living world archaebacteria the three domains of life classification of microbes

  1. Diatomssilica shell, boxlike, golden brown

  2. Euglenoidsflagella, pellicle, eye spot

  3. Parameciumcilia, calcium carbonate shell, gullet

  4. Foraminiferantest, pseudopod, digestive vacuole

Show answer
Correct Option: C
Explanation:

Paramecium consists cilia on the cell wall which is made up of the pellicle, paramecium does not contain calcium carbonate shell and the food in the paramecium passes through the cell mouth into the gullet.

So, the correct option is 'Paramecium cilia, calcium carbonate shell, gullet.'

Which of the following bacteria is present in the rumen of cattle ?

botany the living world archaebacteria the three domains of life classification of microbes

  1. Azotobacfer

  2. Rhizoblum

  3. Methanobacterium

  4. Azospirilium

Show answer
Correct Option: C
Explanation:

Methanobacterium is found in the rumen (a part of the stomach) of cattle. A lot of cellulosic material is also available in the rumen. In rumen, these bacteria help in the breakdown of cellulose and play an important role in nutrition of cattle.

Select the correct combination of the statements (i - iv) regarding the characteristics of certain organisms.
(i) Methanogens are archaebacterial which produces methane in marshy areas.
(ii) Nostoc is a filamentous blue-green alga which fixed atmospheric nitrogen.
(iii) Chemosynthetic autotrophic bacteria synthesize cellulose from glucose.
(iv) Mycoplasma lacks a cell wall and can survive without oxygen.

botany the living world archaebacteria the three domains of life classification of microbes

  1. (ii) and (iii)

  2. (i), (ii) and (iii)

  3. (ii), (iii) and (iv)

  4. (i), (ii) and (iv)

Show answer
Correct Option: D
Explanation:

Methanogens produce methane gas, nostoc fixes atmospheric nitrogen, mycoplasma lacks a cell wall and can survive without oxygen.

So, the correct option is '(i), (ii) and (iv)'.

Organisms living in salty areas are called as

botany the living world archaebacteria the three domains of life classification of microbes

  1. Methanogens

  2. Halophiles

  3. Heliophytes

  4. Thermoacidophiles

Show answer
Correct Option: B
Explanation:

Halophiles can be found in a concentration of salt five times greater than the salt concentration of the ocean.

So, the correct option is 'halophiles'.

Certain bacteria are able to thrive under extreme environmental conditions such as absence of oxygen, high salt concentration, high temperature or highly acidic environment. What are these bacteria called?

botany the living world archaebacteria the three domains of life classification of microbes

  1. Probacteria

  2. Neobacteria

  3. Hardy bacteria

  4. Archaebacteria

Show answer
Correct Option: D
Explanation:
Archaebacteria are the oldest organisms living on the Earth. They are unicellular prokaryotes and belong to the kingdom, Archaea. They were first discovered in 1977 and classified as bacteria. Most archaebacteria appear like bacteria, when observed under the microscope. However, they are quite different from bacteria and eukaryotic organisms. Archaebacteria are found in very harsh conditions such as in the volcanic vents or at the bottom of the sea. They can easily survive in such extreme environment as sea vents releasing sulfide-rich gases, hot springs, or boiling mud around volcanoes.
So the correct option is 'archaebacteria'.

Which of the following mode of reproduction can be seen in archae bacteria?

botany living world and classification of microbes archaebacteria the three domains of life classification of microbes

  1. Sexual reproduction

  2. Asexual reproduction

  3. Horizontal gene transfer

  4. Both B and C

Show answer
Correct Option: B
Explanation:

The archaebacteria are the primitive, single-celled, prokaryotic organisms. These bacteria can reproduce through asexual reproduction. The modes of reproduction include binary fission and fragmentation. The cell divides to form two daughter cells through binary fission. The fragments which are produced have the capability to develop into new organisms. 

Thus, the correct answer is option B. 

These bacteria grow anaerobically on cellulosic material, produce large amount of methane along with $CO _2$ and $H _2$ and are collectively called as methanogens. Examples of such bacteria are:

botany the living world archaebacteria the three domains of life classification of microbes

  1. Melhanobacterium

  2. Mathanobrevibacter

  3. Methanococcus

  4. All of these

Show answer
Correct Option: D
Explanation:

Methanogens are microorganisms that produce methane as a metabolic byproduct in anoxic condition. They include Methanobacterium, Methanobrevibacter and Methanococcus. 

Methanogens can be found 

botany the living world archaebacteria the three domains of life classification of microbes

  1. In swamps

  2. In a cow's stomach

  3. In marshes

  4. All of the above

  5. None of the above

Show answer
Correct Option: D
Explanation:

Methanogens are the primitive bacteria belonging to archaea which are able to produce methane. These organisms can utilise the carbon dioxide and hydrogen gas to form methane. These organisms are found in marshy areas where they produce the marsh gas, in swamps and in the stomach of certain animals. These organisms are responsible for methane production in the stomach of cattle which causes belching.

Thus, the correct answer is option D. 

This taxonomic group of living organisms includes the extreme halophiles, methanogens, and extreme thermophiles. This group has also been extant for about 3.7 billion years, and their cell lacks a nucleus and membrane bound organelles. Which of the following groups of life is being described here?
I. Domain Eukarya
II. Domain Archaea
III. Domain Bacteria        

botany the living world archaebacteria the three domains of life classification of microbes

  1. I only

  2. II only

  3. III only

  4. I and II

  5. II and III

Show answer
Correct Option: B
Explanation:

The archaebacteria are the single-celled, prokaryotic organisms. They do not have well-developed organelles and cellular structures. These organisms can survive in extreme conditions like high temperatures, high salt concentration, high temperature, etc. Some organisms from this group can produce methane through the process of methanogenesis. 

Thus, the correct answer is option B. 

Marsh gas is produced by

botany the living world archaebacteria the three domains of life classification of microbes

  1. Mycoplasma

  2. Myxobacteria

  3. Methanogens

  4. Halophiles

Show answer
Correct Option: C
Explanation:

Marsh gas is also called as biogas. It is also called as methane gas as it primarily consists of methane gas along with hydrogen sulfide and carbon dioxide in minor composition. It is a produced by the decomposition of vegetable matter under water by anaerobic bacteria. The marsh gas is produced by Methanogens that are found in marshes.

Thus, the correct answer is 'Methanogens.'