Tag: botany

Questions Related to botany

Which of the following is mostly used in genetic engineering experiments?

  1. Bacillus subtilis

  2. Rhizobium

  3. Staphylococcus

  4. Escherichia coli


Correct Option: D
Explanation:

Genetic engineering is a branch of science which uses a set of biotechnology techniques and knowledge of cytology and genetics to  bring modifications to an organism's genome.   For such research,  scientists need to store and modify the genes and genetic information from wide range of organisms into organisms that can be easy to transform.  Bacteria more commonly Escherichia coli is used to transform and create the genetically modified bacteria as this can be transformed and stored easily for indefinite periods at -80 C and replicate the modified DNA in short time period.

The uptake of naked DNA by bacteria is called

  1. Conjugation

  2. Transformation

  3. Transfection

  4. Transduction


Correct Option: B

R-II strain of $T 4$ bacteriophage cannot lyse Escherichia coli. Two of its types, R-$II^x$ and R-$II^y$ were allowed to invade the bacterium which lysed because of _________________.

  1. Transformation into wild type

  2. Presence of similar cistrons

  3. Presence of different cistrons

  4. Absence of mutation


Correct Option: A

The colonies of recombinant bacteria appear white in contrast to blue colonies of nonrecombinant bacteria because of

  1. Inactivation of glycosidase enzyme in recombinant bacteria

  2. Nonrecombinant bacteria contain beta galactosidase

  3. Insertional inactivation of $\alpha$-galactosidase in nonrecombinant bacteria

  4. Insertional inactivation of $\alpha$-galactosidase in recombinant bacteria


Correct Option: D

Changes in transcription after linking the cloned DNA of the putative promoter/enhancer region to cloned DNA of the coding region of an unrelated gene, can be measured rapidly with a high degree of sensitivity using.

  1. Transgenic technology

  2. Reporter gene technology

  3. cDNA technology

  4. Gene transfer technology


Correct Option: A

Which one of the following techniques made it possible to genetically engineer living organisms?

  1. Heavier isotope labelling

  2. Hybridization

  3. Recombinant DNA techniques

  4. X-ray diffraction


Correct Option: C
Explanation:

Genetic engineering, also known as recombinant DNA technology, means altering the genes in a living organism to produce a genetically modified organism (GMO) with a new genotype. Various kinds of genetic modification are possible: inserting a foreign gene from one species into another, forming a transgenic organism; altering an existing gene so that its product is changed; or changing gene expression so that it is translated more often or not at all.

Which of the following produces citric acid through fermentation process?

  1. Aspergillus

  2. Streptococcus

  3. Acetobacter

  4. Streptomyces


Correct Option: A
Explanation:
  • Aspergillus produces citric acid through fermentation process.
  • Streptococcus  produces lactic acid through fermentation.
  • Acetobacter produces acetic acid through fermentation.
  • Streptomyces produces antibiotics.
  • So, the correct answer is 'Aspergillus'.

Lipid dissolving enzymes are obtained from

  1. Trichoderma

  2. Streptococcus

  3. Candida

  4. Mucor


Correct Option: C
Explanation:
  • Candida is the fungus that causes infection on the skin or the mucous membrane.
  • The cells of the fungus in order to infect the host cell needs to break the cell membrane and enter the cell. For this purpose the fungi secrets phospholipase and lipase to dissolve the cell membrane which is made us of the lipid bilayer with units of phospholipid present in it.
  • After entering the cell the fungi starts growing on the cell in a parasitic way. The secretions which are released by the fungus cause itching and rashes on the area of infection.
  • Whereas Trichoderma is not an infectious agent but it lives in a symbiotic relationship with many plants. Some species of Trichoderma maybe pathogenic but only to plants.
  • Streptococcus is a disease-causing organism but it causing the disease using the process of hemolytic where it mainly attacks the blood cells and causing their lysis.
  • Mucor is fungus whose growth is seen on the stale bread. It is black colour mold growing on the bread.
  • Therefore the answer Option C is correct as Candida is the only one among the options that secrets lipid dissolving enzymes.

Which of the following is an application of fermentation

  1. Tanning of leather

  2. Curing of tea

  3. Production of wine

  4. All of the above


Correct Option: D
Explanation:
  • Fermentation in the process of tanning leather is used to soften the skin after removing the hair. This done using various bacteria.
  • fermention in curing of tea takes place after the process of disruption. Here the chlorophyll in the ;eves is enzymatically broken and its tannins are released.
  • In production of wine the organism used for fermentation to convert carbohydrate in alcohol.

If all fungi in an environment that perform decomposition were to suddenly die, then which group of organisms should benefit most, due to the fact that their fungal competitors have been removed?

  1. Plants

  2. Protists

  3. Prokaryotes

  4. Animals


Correct Option: C
Explanation:
  • Prokaryotics will be the next group after fungus that will benefit if all the fungus were to die a sudden death.
  • As the protist group consist of mostly disease causing organisms and plants are one that take the benefit from the decomposed material while animals are the those that feed on organisms from first and second tropic level.
  • Prokaryotes mostly have single celled organisms such as bacteria which help in decomposition of the organic waste left by the higher organisms
  • So, the correct answer is 'Prokaryotes'.