Anton van Leeuwenhoek :-))
Answer: Four amino acids.
Explanation:
RNA (ribonucleic acid) and DNA (deoxyribonucleic acid) are polymers made up of long chains of nucleotides. Thus, a nucleotide is the basic building block of nucleic acids and consists of a sugar molecule (ribose in RNA or deoxyribose in DNA) linked to a phosphate group and a nitrogenous base. <u>The nitrogenous bases can be Adenine (A), Thymine (T), Cytosine (C), Guanine (G) or Uracil (U) replacing T in RNA</u>. DNA is the molecule that stores the genetic information to synthesize polypeptides or proteins (set of amino acids). When proteins need to be created, DNA is transcribed into RNA and this RNA is translated in ribosomes to create polypeptides.
Complementarity is the ability to combine with their complement. A and T (or U) are complementary, while C and G are complementary to each other. Complementarity is the principle of replication and transcription, because it is a propery of both DNA and RNA sequences. Their the nucleotide bases at each position of the sequences are complementary, allowing cells to copy information.
Nucleotides in RNA are grouped into codons, which consist of groups of 3 nucleotides where each codon codes for an amino acid. Therefore, <u>the sequence of bases in nucleic acids determines which protein will be synthesized</u>. Protein synthesis begins with a start codon (AUG, which codes for the amino acid methionine) and ends with a stop codon (UGA, UAG and UAA). So, if there are 15 nucleotides, there are 15 bases. Since they are grouped in groups of 3, we will have a polypeptide of 4 amino acids.
<u>3 nucleotides form a codon, so 12 nucleotides form 4 codons giving 4 amino acids. The last codon, is formed by the last 3 nucleotides and form the stop codon that stop protein synthesis</u>.
Reading through the entire investigation before beginning the procedure can help prevent accidents by giving you the knowledge of what to do beforehand and preparing you for what is to come.
Answer:
a. The operon is under positive control
a.) Loss of enzyme synthesis results from loss of regulatory R gene product which is regulated in the presence of Tis ophane for transcription. Absence of (Tis), transcription is positively controlled by regulatory Rprotein
b.) The proposed model reveals Tis / B complex prevents Tis enzymes from undergoing transcription through the RB operator by binding to the B region
the role of the R protein is
-decrease affinity of Tis / B complex to B region of RB
-bind to the R region on RB
- change the conformation of B region
- yield decreased affinity of Tis / B complex when R gene is lacking preventing transcription in the process
Effects of the RB mutations is that R protein will not bind to Tis / B complex to reduce transcription