If a lot of tryptophan is present, the operon will be repressed.
Under intermediate amounts of tryptophan, the change to stop codons would cause the ribosome to stall and therefore would mimic as if there were no tryptophan present.
If no tryptophan present, the operon would be maximally expressed.
a - True. The ribosome would always be stalled in the leader sequence - so this wouldn't matter. However, the operon would still be transcribed because the repressor would be active (remember Trp operon is controlled both by attenuation and repression). True as long as there's not much tryptophan to activate the repressor!
b- True - With no tryptophan the repressor isn't engaged and the ribosome is stalled in the leader sequence.
c- Matters about how much tryptophan is available. So True if there's lots of tryptophan available.
d- I would choose this one as all of the above could be true depending on the levels of tryptophan.
<h2>Heteroduplex DNA</h2>
Explanation:
With respect to double strand break repair, heteroduplex DNA can be formed when broken strands invade non sister chromatids
- Heteroduplex DNA is formed during homologous genetic recombination
- Holliday junction is formed during the break model of homologous recombination by break in DNA and strand invasion,each invading strand joins to the broken end of other DNA molecule,creating a Holliday junction
- Two types of cleavage occurs in this type of junction-horizontal and vertical cleavage
- Cleavage in vertical plane produces cross over recombinant consisting of 2 heteroduplex DNA
Answer:
physical
Explanation:
example: water freezing into ice
there is no change in the chemical properties, frozen water is still water
The dissolved sugar molecules is distributed evenly all over the solution.
The equilibrium is reached through diffusion. Diffusion is the net movement of molecules and atoms from a high concentration to area of lower concentration. This is considered as the result of the movement of molecules. Diffusion is driven by a gradient until the molecules are distributed randomly and uniformly all throughout the solution. This can be manifested by perfume sprayed in the air, dye dropped in a water. The distinguishing features of diffusion is that particle move randomly and in uniform pattern.
