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#Question id: 15268

During DNA isolation, phenol / chloroform extraction is performed to remove

#SCPH28 | Zoology
  1. to remove lipid from DNA homogenate
  2. to remove RNA from DNA homogenate
  3. to remove protein from DNA homogenate
  4. to remove from DNA homogenate
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#Question id: 9283

#SCPH06 I Botany

Organization of the protein complexes the photosystems I and II Are spatially separated in the thylakoid membrane, choose the correct arrangement of PSI and PSII on the membrane ;

a.) The PSI reaction centre and its associated antenna pigments and electron transfer proteins, as well as the coupling-factor enzyme that catalyzes the formation of ATP, are found almost exclusively in the stroma lamellae and at the edges of the grana lamellae

b.) The PSI reaction centre, along with its antenna chlorophylls and associated electron transport proteins, is located predominantly in the stromal lamellae

c.) The PSII reaction centre and its associated antenna pigments and electron transfer proteins, as well as the coupling-factor enzyme that catalyzes the formation of ATP, are found almost exclusively in the stroma lamellae and at the edges of the grana lamellae

d.) The PSII reaction centre, along with its antenna chlorophylls and associated electron transport proteins, is located predominantly in the grana lamellae

Which of the following given combination correct?
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#Question id: 15657

#SCPH01 Biochemistry

You are studying a new strain of E. coli that can utilize the disaccharide melibiose very efficiently. You find that utilization depends on the enzyme melibiase, which is encoded by the gene Mel1. Mel1 is not expressed unless melibiose is present in the growth medium.
You next construct a MelA– MelB– double mutant, which gives the following behavior:
 
Which of your two models is consistent with this new data?
a) the MelA- MelB- double mutant is identical to the MelB- mutant
b) MelA- is epistatic to MelB-
c) MelB- is epistatic to MelA-
d) the MelA- MelB- double mutant is identical to the MelA- mutant
Which of the following is the correct prediction about the double mutants?
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#Question id: 11140

#SCPH28 | Zoology

Although the membrane of a "resting" neuron is highly permeable to potassium ions, its membrane potential does not exactly match the equilibrium potential for potassium because the neuronal membrane is also ________.
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#Question id: 2974

#I Life Science/ Life Sciences Group – I-V

Following statements are regarding to control of the G1–S phase transition in budding yeast.

A. G1 cyclin-CDK complexes stimulate the formation of G1/S phase cyclin-CDKs, which then initiate bud formation, centrosome duplication, and DNA replication. In yeast, the G1 cyclin gene is called CLN3.

B. Once sufficient Cln3 is synthesized from its mRNA, Cln3-CDK complexes phosphorylate and activate the transcriptional repressor Whi5.

C. Phosphorylation of Whi5 promotes its export out of the nucleus, allowing the transcription factor complex SBF to induce transcription of the G1/S phase cyclin genes CLN1 and CLN2 as well as other genes important for DNA replication.

D. Once produced, Cln1/2-CDKs contribute to further Whi5 phosphorylation. This positive feedback loop ensures the rapid accumulation of G1/S phase cyclin-CDKs.

Which of the following statements are correct?
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#Question id: 5742

#SCPH06 I Botany

When an allotetraploid (AABB) is backcrossed to one of its progenitor species (AA), a sterile progeny is produced.  The genomic composition of this sterile individual can be best represented by