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TLS Online TPP Program

#Question id: 425

Which is usually the slowest way to regulate a reaction in a metabolic pathway?

#SCPH28 | Zoology

  1. allosteric modulation

  2. covalent modification

  3. changing the enzyme concentration

  4. usually equally as fast

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TLS Online TPP Program

#Question id: 15234

#SCPH01 Biochemistry

Polymerisation of acrylamide and bis-acrylamide gel takes place by free radical contribution due to
A) APS
B) Riboflavin
C) TEMED
D) SDS
TLS Online TPP Program

#Question id: 13094

#SCPH28 | Zoology

You are studying a specific gene in yeast, and you want to express that yeast gene in E. coli. Your task is to design a strategy to insert the yeast gene into the bacterial plasmid. Below is a map of the area of the yeast genome surrounding the gene in which you are interested.
 
The distance between each tick mark placed on the line above is 100 bases in length
Below are the enzymes you can use, with their specific cut sites shown 5’-XXXXXX-3’ 3’-XXXXXX-5’
 
The plasmid is 5,000 bases long and the two farthest restriction enzyme sites are 200 bases apart. The plasmid has an ampicillin resistance gene somewhere on the plasmid distal from the restriction cut sites.
                                     
You transform your ligation planned in which two restriction enzymes would you use to design a way to get the insert into the vector if you had to use two enzymes simultaneously, into bacteria and plate the bacteria on Petri plates containing ampicillin. (You actually transform six different ligation mixtures, which are described below, into six different populations of cells, and plate each transformation onto a different plate, because you want to do all of the correct controls.) The next day you come in to lab to look at how many colonies of bacteria are on each plate. You are really excited, because the number of colonies you see on each plate tells you that the entire procedure worked! Which of the three following patterns of number of colonies did you see in order to conclude that you had a successful transformation?
In this table, DV = digested vector. DYG = digested yeast genome.
 
a) Pattern-1, DV only + Ligase→No colonies b/c you have digested with 2 different restriction enzymes that can’t ligate together 
b) Pattern-2, DYG only + Ligase→ No colonies because all you transformed is the digested, linear yeast DNA.
c) Pattern-3, Water + Ligase→ No plasmid with the ampicillin resistance gene (or any DNA) was transformed into the bacteria and so it won’t grow in the presence of ampicillin.
d)Pattern-3, DV + DYG + Ligase→Colonies. The plasmid and yeast gene can ligate together to form a functional plasmid that will express the ampicillin resistance gene.
e) Pattern-1 and 2 only, DV + DYG (No Ligase) →No colonies because, although you have both digested plasmid and a digested yeast gene with complementary sticky ends
Which of the following statements about these ligations and their pattern is correct?
TLS Online TPP Program

#Question id: 12718

#SCPH06 I Botany

primary disruptions could be signaling the plant that a change in environmental conditions has occurred and that it’s time to respond by altering existing pathways or by activating stress-response pathways. At least five different types of stress-sensing mechanisms can be distinguished:

                       

                          COLUMN I

 

 

                              COLUMN II

 

A) Physical sensing

 

 

i) usually results from the detection of by-products that accumulate in cells due to the uncoupling of enzymatic or electron transfer reactions, such as the accumulation of ROS during stress caused by too much light.

 

 

B) Biophysical sensing

 

 

ii) often involves the presence of specialized proteins that have evolved to sense a particular stress; for example, calcium channels that can sense changes in temperature and alter Ca2+ homeostasis.

 

 

C) Metabolic sensing

 

 

iii) refers to modifications of DNA or RNA structure that do not alter genetic sequences, such as the changes in chromatin that occur during temperature stress.

 

 

D) Biochemical sensing

 

 

iv) refers to the mechanical effects of stress on the plant or cell structure, for example, the contraction of the plasma membrane from the cell wall during drought stress.

 

 

E) Epigenetic sensing

 

 

v) might involve changes in protein structure or enzymatic activity, such as the inhibition of different enzymes during heat stress.

 

 

  
Match the correct sequence sensing mechanism during in stress;
TLS Online TPP Program

#Question id: 14121

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

Which of the following is not the classification of SCOP?
TLS Online TPP Program

#Question id: 1723

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

Which of the following statements is the single best description of the location where adaptive immune responses arise?