Tag: bacteria; benefits and harmful effects

Questions Related to bacteria; benefits and harmful effects

Which one of the following is the basis of biological control of crown gall?

botany bacteria bacteria - introduction, shape and structure bacteria: types and structure bacteria; benefits and harmful effects

  1. Agro bacterium radiocasted strains contain a plasmid which directs the synthesis of bactenocin

  2. The Ti(tumour inducing) plasmid in Agro bacterium tumefactions is integrated with host plant DNA and is transcribed into mRNA

  3. The cloning strategy leading to a composite(chimeric) plasmid harbouring two or more genes that code for distinct bacteriocins against phytopathogenic bacteria

  4. Agrobacterium radiobacter plasmid interferes with the production of auxin by a tumefaction

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Correct Option: A

Match items in Column I with those in Column II -
 

Column I Column II
(A) Peritrichous flagellation (J) Ginkgo
(B) Living fossil  (K) Macrocystes
(C) Rhizophore (L) Escherichia coli
(D) Smallest flowering plant (M) Selaginella
(E) Largest Perennial alga (N) Wolffia

Select  the correct answer with the following

botany bacteria bacteria - introduction, shape and structure bacteria: types and structure bacteria; benefits and harmful effects

  1. A L ; B J; C M ; D N ; E K

  2. A K ; B J; C L ; D M; E N

  3. A J ; B K; C N ; D L; E K

  4. A N ; B L; C K ; D N; E J

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Correct Option: A

Which one of the following is the most important criterion used to classify living organisms into three primary kingdoms, namely-Archaea, Eubacteria and Eukarya?

botany bacteria bacteria - introduction, shape and structure bacteria: types and structure bacteria; benefits and harmful effects non cellular organism : virus world of virus

  1. Genetic relatedness

  2. Morphological characters

  3. Physiological characters

  4. Phenotypic characters

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Correct Option: A

Rhodopseudomonas and Rhodospirillum are ______________.

botany bacteria bacteria - introduction, shape and structure bacteria: types and structure bacteria; benefits and harmful effects non cellular organism : virus world of virus

  1. Purple non-sulphur bacteria

  2. Green non-sulphur bacteria

  3. Green sulphur bacteria

  4. Purple sulphur bacteria

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Correct Option: A

Yeast die when alcohol concentration reaches about $13$%, still yeast perform alcholic fermentation why?

botany bacteria bacteria - introduction, shape and structure bacteria: types and structure bacteria; benefits and harmful effects non cellular organism : virus world of virus

  1. To obtain ATP

  2. Utilization of $O _{2}$

  3. For oxidation of $NADH _{2}$

  4. Obligate aerobic

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Correct Option: A

Cell division is a type of reproduction in 

botany bacteria bacteria - introduction, shape and structure bacteria: types and structure bacteria; benefits and harmful effects non cellular organism : virus world of virus

  1. Unicellular organisms

  2. Multicellular organisms

  3. Both A and B

  4. None of the above

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Correct Option: A
Explanation:

Cell division is the process in which a parent cell divides into two or more daughter cells. The unicellular organism divides and results in the formation of daughter cells and hence, cell division is a type of reproduction in unicellular organisms. Thus, the correct answer is option A.

Choose the correct answers from the alternatives given.
Surface appendages used by -bacteria to attach to one another and to host organisms are called:

botany bacteria bacteria - introduction, shape and structure bacteria: types and structure bacteria; benefits and harmful effects non cellular organism : virus world of virus

  1. thylakoids

  2. mesosomes

  3. pili

  4. spirilla

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Correct Option: C
Explanation:
A pilus is a thin, rigid fiber made of protein that protrudes from the cell surface. The primary function of pili is to attach a bacterial cell to specific surfaces or to other cells. So, the correct option is 'pili'.

Which of the following organisms do not depend on reproduction to exchange genetic information?

botany bacteria bacteria - introduction, shape and structure bacteria: types and structure bacteria; benefits and harmful effects non cellular organism : virus world of virus

  1. Animals

  2. Plants

  3. Bacteria

  4. Fungi

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Correct Option: C
Explanation:

Bacteria have three mechanism for genetic information transfer without undergoing reproduction-
1. Transformation- take up free fragment of DNA floating in medium. 
2. Transduction- transfer of DNA by a virus bacteriophage.
3. Conjugation- direct cell to cell transfer of DNA mediated by plasmid. So, option C is correct, all other options depend on reproduction for exchange of genetic material.

Select the pair that shows the same relationship as the animals in the box.
Amoeba : Paramecium.

botany bacteria bacteria - introduction, shape and structure bacteria: types and structure bacteria; benefits and harmful effects non cellular organism : virus world of virus

  1. Rhizopus : Chlamydomonas

  2. Candida : Saccharomyces

  3. Pteridium : Fasciola

  4. Albugo : Adiantum

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Correct Option: A
Correct sequence of layer of bacterial cell envelope from outward to inward is
botany the world of microbes bacteria - introduction, shape and structure bacteria: types and structure bacteria; benefits and harmful effects non cellular organism : virus world of virus

  1. Cell wall $\rightarrow$ Glycocalyx $\rightarrow$Cell membrane

  2. Cell membrane $\rightarrow$ Glycocalyx $\rightarrow$ Cell wall

  3. Glycocalyx $\rightarrow$ Cell wall $\rightarrow$ Cell membrane

  4. Glycocalyx $\rightarrow$ Cell membrane $\rightarrow$ Cell wall

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Correct Option: C
Explanation:

Glycocalyx is the outermost layer of the cell envelope. Cell wall lies between plasma membrane and glycocalyx.

So, the correct answer is 'Glycocalyx → Cell wall → Cell membrane'.