Biology · Environmental Studies

Microbiology and Nitrogen Cycle

1,029 Questions

This hub focuses on microbiology and the nitrogen cycle, covering essential concepts about bacteria and soil microbes. Topics include nitrogen fixation, bacterial structures, and soil microbial processes. These concepts are frequently tested in general science sections of various competitive exams.

Nitrogen fixing bacteriaGram-positive bacteriaBacterial flagellaDenitrifying bacteriaAmmonia conversion processBacterial resting spores

Microbiology and Nitrogen Cycle Questions

Multiple choice zoology respiratory system do plants breathe? plant respiration respiration-plants

The growth of which group of bacteria will be slow in comparison to the others?

  1. Obligate aerobes

  2. Obligate anaerobes

  3. Facultative aerobes

  4. Facultative anaerobes
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
  • The growth of Obligate aerobes will be slow in comparison to the other bacteria.
  • These group of bacteria require oxygen to grow as they cannot respire anaerobically.
  • Its growth depends on aerobic respiration and use oxygen as a terminal electron acceptor.
  • The correct answer is OPTION A.
Multiple choice zoology respiratory system do plants breathe? plant respiration respiration-plants

Mark the correct statement.

  1. Anaerobes grow in absence of oxygen.

  2. Aerophiles can grow in complete absence of oxygen.

  3. Aerobes can grow in absence of oxygen.

  4. Obligate anaerobes can live in the presence of abundant oxygen.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The first statement is the correct one which say the organism grow with no oxygen is called as anaerobes.

So the correct option is 'Anaerobes grow in absence of oxygen'.

Multiple choice botany breeding and biotechnology branches of biotechnology gene cloning biotechnology and genetic engineering

Which of the following bacteria are used in study of 'genetics'?

  1. E. coli

  2. Bacillus

  3. Pseudomonas

  4. Rhizobium
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
E. coli is the most well-understood bacterium and is an extremely important model organism in many fields of research, particularly molecular biology, genetics, and biochemistry. It is easy to grow under laboratory conditions, and research strains are very safe to work with. As with many bacteria, E. coli grows quickly, which allows many generations to be studied in a short time. Under ideal conditions, E. coli cells can double in number after only 20 minutes. The genetics of E. coli are well-understood and can be readily manipulated.
Therefore, the correct answer is option A.
Multiple choice evs modern agriculture agricultural practices in india different types of farming and agriculture various agricultural practices

Which is wrong among the following?

  1. Anabaena and Nostoc are capable of fixing nitrogen in free state.

  2. Root nodule forming nitrogen fixers live as aerobes under free living state.

  3. Phosphorus is a constituent of cell membranes, certain nucleic acids and all proteins.

  4. Nitrosomonas and Nitrobacter are chemoautotrophs.
Reveal answer Fill a bubble to check yourself
A Correct answer
Multiple choice biology food and it's constituents functions and principal sources of lipids chemical organization in living beings lipids

During symbiotic biological nitrogen fixation. The recognition of rhizobiahost interaction involves two classes of molecules there are _______________.

  1. Lectins an lipids

  2. Lectins and Polysaccharides

  3. Flavonoids and lipids

  4. Lectins and Alkaloids
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

In the symbiotic relationship between legumes and rhizobia, the initial recognition involves lectins (on the plant side) and specific polysaccharides or lipids on the bacterial surface.

Multiple choice biology transport in plants transport of food, water and minerals theories of translocation transport in the phloem of plants

In the root nodules of legumes, leghaemoglobin is important because it

  1. Transports oxygen to the root nodule.

  2. Acts as an oxygen scavenger.

  3. Provides energy to the nitrogen fixing bacterium.

  4. Acts as a catalyst in transamination.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The root nodule bacterium is microaerobic in the sense that it requires oxygen but the high concentration of oxygen is detrimental to nitrogen-fixing enzyme system. Here leghaemoglobin proves beneficial, it absorbs or binds oxygen so that there is no free oxygen left in the nodule and then carries micro-amounts of oxygen to the nodule bacteroids. Thus the correct answer is option B.

Multiple choice biology interdependence in living beings - plants and animals animals as consumers scavengers and decomposers interdependence between plants and animals

Which of the following microorganisms convert nitrogenous waste into nitrogen compound?

  1. Bacteria and Fungi

  2. Fungi and Protozoan

  3. Protozoan and Algae

  4. Protozoan and Bacteria
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Bacteria and fungi belongs to the class of decomposers. They act on the waste materials and converts the nitrogen present in the waste to useful nitrogenous compounds. It also increases the nitrogen content of the soil and increases the fertility of the soil.

So, the correct answer is option A.

Multiple choice biology interdependence in living beings - plants and animals animals as consumers scavengers and decomposers interdependence between plants and animals

Which one of the following is genetically improved bacteria for pollution control.

  1. Pseudomonas

  2. Rhlzobium

  3. N!trobacter

  4. Nttrosomonas
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Pseudomonas species, particularly Pseudomonas putida, have been genetically modified to degrade various environmental pollutants including hydrocarbons, pesticides, and heavy metals. This makes them valuable for bioremediation efforts to clean up contaminated sites. The other options are important soil bacteria but not primarily known for pollution control.

Multiple choice botany energy flow in an ecosystem biogeochemical cycle nutrient cycles species, communities and ecosystems

Which of the following are the examples of biogeochemical cycle?

  1. Nitrogen cycle

  2. Krebs cycle

  3. Electron cycle

  4. All of the above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

A biogeochemical cycle involves biological, geological and chemical factors. The circulation of chemical nutrients like carbon, oxygen, nitrogen, phosphorus, calcium, and water, etc. between biotic and abiotic components of the biosphere is known as a biogeochemical cycle.
So, the correct option is option A.