Mutations. Definition. A Mutationoccurs when a DNA gene is damaged or changed in such a way as to alter the genetic message carried by that gene. A Mutagen is an agent of substance that can bring about a permanent alteration to the physical composition of a DNA gene such that the genetic message is changed
Answer:
The correct answer is option B, that is, promoter, operator, gene.
Explanation:
In a prokaryote, just in front of the operator, the promoter is located, and just in front of the structural genes, the operator is located. All these in combination give rise to an operon.
Any gene, which codes for an enzyme or a structural protein is termed as a structural gene, in the lac operon, a structural gene codes for three distinct kinds of enzymes. A short sequence of DNA is situated just in front of the structural gene, which is known as the operator. An operator functions as a switch for transcription, that is, it monitors whether the process of transcription will take place or not.
Just in front of an operator, a sequence of a promoter is present, and for the transcription and translation of all the structural genes, the RNA polymerase needs to combine first with the promoter. In case, if no transcription is to take place, then the operator allows the repressor to bind with it and prevent the attachment of RNA polymerase with the promoter. Hence, the correct sequence of a prokaryotic operon is a promoter, operator, and gene.
The answer to this question would be: increased food height
Giraffe becomes tall because its food height is increased. In this case, the environmental pressure on Giraffe would be the increased height of the food.
The taller giraffe has access to higher food. Then, the giraffe with the higher chance of survival in this scenario would be the giraffe with a taller height.
An alternative approach to this experiment would be the use of Spectroscopy. Instead of trying to visualize and guess the fraction with the most intense color, the exact fraction could be found with Spectroscopy. A range of fractions that are the most intense are measured with the absorbance value for each one. The fraction with the highest absorbance value will be the most intense fraction.This method guarantees that the <span>correct retention volume is recorded.</span>