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TLS Online TPP Program

#Question id: 3818

DNA replication is studied in a newly discovered bacterium. It takes 30 min for the bacterium to complete a round of replication at 37oC. A Meselson-Stahl-type experiment was performed. The bacteria were grown for several generations in 14N-medium and then switched to 15N-medium. The DNA molecules were then analyzed.

If the mechanism of DNA replication in this bacterium were semi-conservative, what results would be found when the double-stranded DNA was analyzed in a CsCl density gradient after three generations in 15N-medium?

#Unit 3. Fundamental Processes

  1. The DNA would form three bands: one with hybrid density, one with light density, and one with heavy density.

  2. The DNA would form one band with hybrid density.

  3. The DNA would form two bands: one with heavy density and one with hybrid density.

  4. The DNA would form two bands: one with light density and one with hybrid density.

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TLS Online TPP Program

#Question id: 32320

#Unit 1. Molecules and their Interaction Relevant to Biology

The standard free-energy change for given reactions, using the equilibrium constants given for the reactions at 25°C and pH 7.0 will be
TLS Online TPP Program

#Question id: 12708

#Unit 8. Inheritance Biology

800 meiocytes with the genotype AaBb undergoes meiosis with 60% chance of crossing over with A and B. How many recombinant gamete form?
TLS Online TPP Program

#Question id: 5727

#Unit 8. Inheritance Biology

Pairing occurs during the prophase of meiosis I, after the chromosomes have been duplicated. Centromere mention as 1, 2, 3 and 4

Which of the following is correct statement Types of disjunction in a translocation heterozygote during meiosis I.

A) Centromeres 1 and 3 go to one pole and centromeres 2 and 4 go to the other pole, producing non fuctional gametes.

B) Centromeres 1 and 2 go to one pole and centromeres 3 and 4 go to the other pole, producing viable gametes.

C) Centromeres 2 and 3 go to one pole and centromeres 1 and 4 go to the other pole, producing euploid gametes.

D) Centromeres 2 and 3 go to one pole and centromeres 1 and 4 go to the other pole, producing non viable gamete
TLS Online TPP Program

#Question id: 19367

#Unit 12. Applied Biology

First phase genetic engineering is done for production of 
1. Human growth hormone
2. Insulin 
3. Interferon
Which of the above products are correct?
TLS Online TPP Program

#Question id: 5145

#Unit 5. Developmental Biology

Doris Taylor’s research group used detergents to remove all the cells from a cadaveric rat heart, which left behind the natural extracellular matrix. Proteins such as fibronectin, collagen, and laminin held together the rest of the extracellular matrix and maintained the intricate shape of the heart. The researchers then infused this extracellular matrix scaffold with cardiomyocyte progenitor cells. Surprisingly, these cells differentiated and organized into a functionally contracting “recellularized” heart. The behavior of extracellular matrix scaffold can promote the differentiation and rebuilding of a beating heart is analogous to which of the interactions?