Download App

Enhancement of Food Production — BIOLOGY STD 12 Science — Question

Maharashtra BoardEnglish MediumSTD 12 ScienceBIOLOGYEnhancement of Food Production3 Marks
Question
What are cyanobacteria? Give any two examples cyanobacteria as biofertilizers.
✓

Answer

  1. Cyanobacteria are aerobic, photosynthetic, $N_2$_ fixing microorganisms.
  2. They are aquatic or terrestrial.
  3. They may be free-living or symbiotic.
  4. They may be heterocystous or non- heterocystous. Heterocyst is the site of nitrogen fixation.
  5. e.g. Free living cyanobacteria are Anabaena, Nostoc, Tolypothrix, Plectonema, Oscillatoria.
  6. Anabaena and Nostoc have symbiotic relationship with lichens.
  7. Anabaena is also symbiotically associated with Azolla and Cycas.

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

More "Answer the following questions in detail." from Enhancement of Food Production→Enhancement of Food Production — all question types→BIOLOGY STD 12 Science question papers→Maharashtra Board STD 12 Science question papers→Maharashtra Board question paper generator→

Similar questions

Column AColumn B
(1) Forebrain————–
(2) Midbrain————–
(3) Hindbrain————–
→
  1. List the two methodologies which were involved in human genome project. Mention how they were used.
  2. Expand ‘YAC’ and mention what was it used for.
→
How do ‘pills’ act as contraceptives in human female?
→
Although sexual reproduction is a long drawn, energy-intensive complex form of reproduction, many groups of organism in Kingdom Animalia and Plantae prefer this mode of reproduction.
Give at least three reasons for this.
→
What will happen to an ecosystem if:
All producers are removed.
→
With respect to Messelson and Stahl’s Experiment, answer the following questions:
  1. Identify the method used to distinguish between heavy and light isotopes of nitrogen.
  2. With the help of diagrams, compare the results for the DNA isolated after 20 minutes of experiment with the DNA which was isolated after 40 minutes.
→
Explain BOD and its effects on aquatic ecosystem.
→
Where are the Leydig cells present? What is their role in reproduction?
→
Bee keeping practice is a good income generating industry. Write the different points to be kept in mind for successful bee keeping. Write the scientific name of the most common Indian species used for the purpose.
→
Mention any two human diseases caused by roundworms. Name their causative agents and their mode of transmission into the human body.
→