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Explain how two different species of rabbits could have developed from a common ancestor?

The population of rabbits (common ancestor) must have gotten seperated to form two populations. This could have happened due to a geographical barrier (such as an earthquake) . These two environment must hav...
PJ
Answered by Precious J. Biology tutor
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An electron is traveling at a velocity of 500m/s perpendicular to a uniform magnetic field. A force of magnitude 4.32 x10^(-16) N is acting on the electron, what is the magnetic flux density of the field?

F=BQv so B=F/Qv (Q is the charge of an electron, 1.6 x10 -19 C) so B=4.32 x10 -16 / (1.6 x10 -19 x 500) = 5.4 T
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Answered by Christian J. Physics tutor
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What product would you expect to obtain when reacting ethanal (or acetaldehyde) with potassium cyanide (KCN) in dilute acid? Draw a curly arrow mechanism for this transformation, and determine whether you obtain one enantiomer or a racemic mixture.

The product obtained is a cyanohydrin, with the formula CH3CH(OH)(CN) where the cyanide anion has acted as a nucleophile towards the aldehyde. The mechanism would first show the lone pair on the carbonyl oxy...
AS
Answered by Alex S. Chemistry tutor
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Translation occurs in living cells. Explain how translation is carried out, from the initiation stage onwards.

Translation is the process where mRNA in the cytoplasm becomes a functional protein. Translation follows transcription, where an mRNA for a protein-coding gene is made. The mRNA leaves the nucleus through po...
TM
Answered by Tessa M. Biology tutor
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Explanation of the lac operon, based on 9700/41/M/J/18 Question 3

It is made up of 3 genes: lacZ, lacY and lacA which encode for B-galactosidase (LacZ), lactose permease (LacY), and another enzyme (not studied at A level) respectively.The functions of LacZ (the enzyme) is ...
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Answered by Jose V. Biology tutor
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