Tag: archaebacteria

Questions Related to archaebacteria

Bacteriorhodopsin pigment is associated with ________________.

  1. Red sea formation

  2. Red tide formation

  3. Complementary chromatic adaptation

  4. ATP formation


Correct Option: A

Choose the correct answers from the alternatives given.
Facultative anaerobes:

  1. are photosynthetic

  2. do not always need oxygen

  3. are killed in an oxygenated environment

  4. require a constant supply of oxygen


Correct Option: B
Explanation:

A facultative anaerobe is an organism that makes aerobic respiration if oxygen is absent.

So, the correct option is 'do not always need oxygen'.

Choose the correct answers from the alternatives given.
Which bacteria produces methane as byproduct

  1. Green sulphur

  2. Methanogens

  3. Blue-greens

  4. Rickettsias


Correct Option: B
Explanation:
Methanogens are microorganisms that produce methane as a metabolic byproduct in hypoxic conditions. So the correct option is 'Methanogens'.

Choose the correct answers from the alternatives given.
Which of the following archaea would live at a deep-sea vent?

  1. Heterotrophic nutrition

  2. Prokaryotic organisation

  3. Presence of flagella

  4. Rigid cell wall


Correct Option: D
Explanation:

Archaea have rigid cell walls which help in living at a deep-sea vent.

So, the correct option is 'Rigid cell wall'.

Choose the correct answers from the alternatives given.
During bacterial conjugation there is

  1. a partial but mutual exchange of genetic material between the conjugants

  2. only a partial transfer of genetic material from one conjugant to the other

  3. a mutual and complete exchange of genetic material between two conjugants

  4. a complete transfer of genetic material from one conjugant to the other


Correct Option: D
Explanation:
Bacterial conjugation is the transfer of genetic material between bacterial cells by direct cell-to-cell contact or by a bridge-like connection between two cells. So the correct option is 'a complete transfer of genetic material from one conjugant to the other'.

Choose the correct answers from the alternatives given.
Which of the following archaea would live at a deep-sea vent?

  1. Thermoacidophile

  2. Halophile

  3. Methanogen

  4. Parasitic forms


Correct Option: A
Explanation:

A thermoacidophile is an extremophilic microorganism that is both can grow under conditions of high temperature and low pH.

So, the correct option is 'Thermoacidophile'.

How are Archea different from Bacteria

  1. can form Methane

  2. have different rRNA sequences

  3. do not have peptidoglycan in their cell walls

  4. all of these are correct


Correct Option: D
Explanation:
Archea are considered to be primitive than the Eubacteria, having properties more similar to Eukaryotes as compared to Eubacteria. Some of the features that are different from Eubacteria are, they are found in extremes of temperature, most of them are chemoautotrophs or chemoheterotrophs, Methanogens are a type of chemoheterotrophs that produce methane as a metabolic byproduct, they have pseudomurein or peudopeptidoglyclans in their cell wall. 
So, the correct option is 'all of these are correct'

Thermococcus, Methanococcus and Methanobacterium exemplify 

  1. Bacteria that contain a cytoskeleton and ribosomes

  2. Archaebacteria that contain protein homologous to eukaryotic core histones

  3. Archaebacteria that lack any histones resembling those found in eukaryotes but whose DNA is negatively supercoiled

  4. Bacteria whose DNA is relaxed or positively supercoiled but which have a cytoskeleton as well as mitochondria


Correct Option: B
Explanation:

ThermococcusMethanococcus and Methanobacterium are archaea whose histones are shorter than eukaryotic histones and are assembled in tetramers.

So the correct answer is' Archaebacteria that contain protein homologous to eukaryotic core histones'

Which of the following statements is incorrect regarding the structure of a typical bacterial cell?

  1. Cells possess naked circular DNA which is folded to form nucleoid.

  2. Cells are surrounded by a peptidoglycan cell wall and a mucilaginous sheath.

  3. Cells possess well developed membrane bound cell organelles.

  4. Ribosomes in these cells are 70S in nature.


Correct Option: C
Explanation:

The bacterial cell is a prokaryotic type of cell which lacks membrane-bound cell organelles.

So, the correct option is 'Cells possess well-developed membrane-bound cell organelles.'

Read the following statements regarding methanogens and select the correct option.
(i) They are included in the group Archaebacteria.
(ii) They are responsible for the production of biogas in gobar gas plants.
(iii) They live in hot sulphur springs.
(iv) They are strictly anaerobic. 

  1. Statements (i) and (ii) are correct.

  2. Statements (i), (ii) and (iv) are correct.

  3. Statements (ii), (iii) and (iv) are correct.

  4. All statements are correct.


Correct Option: A
Explanation:

Archaebacteria differ from other bacteria in having a different cell wall structure and this feature is responsible for their survival in extreme conditions. Methanogens are present in the gut of several ruminant animals such as cows and buffaloes and they are responsible for the production of methane (biogas) from the dung of these animals. Methanogens are obligate anaerobes.

So the correct option is "Statement(i) and (ii) are correct".