Question

rRNA sequences are among the most highly conserved in nature. What does the word conserved mean in this context? . (1) Why are rRNA sequences so strongly conserved? . (2)

The different stages of translation use several factors that are not a part of the ribosome. What are these factors, meaning what are they made of? . (1) (2) Why are they not considered to be a part of the ribosome? . (2)

The hydrophobic effect helps explain why proteins fold into stable three-dimensional shapes. In other words is one of the most important components of tertiary structure of proteins. Explain how it works. How do both hydrophilic and hydrophobic R groups lead to folding via the hydrophobic effect? (2)

The part of all amino acids that they share includes both a positively charged side group and a negatively charged group. Despite this, most amino acids in actual proteins lack any charge. How is this possible? (2)

Answer 1

Solution:

Rna sequences are among the most conserved in nature. Here conserved means, they do not vary among species. From their primary structure( building blocks) to their functional conformation, they are similar and execute same or similar functions. The rRNA seauences are heavily conserved. The ribosome execute protein synthesis in prokaryotes and eularyotes. The large and small ribosomal rna are formed of different rRNA sub-units and proteins. In prokaryotes the small rRNA are formed of 16S rRNA. Many phylogenitic studies make use of this rRNA for identification of strains. Also the rRNA in large ribosomal sub unit act as ribozyme. They execute peptidyl transferase reaction that leads to peptide bond formation. Since the process of protein synthesis, it requires highly conserve megadalton machinery to execute this.

During translation several factors associate with ribosomes that are not part of the ribosome. Such factors are proteins that are classified into initiation factors, elongation factors, termination factors and ribosome recycling factors. These factors assit ribosomes during major steps in protein synthesis like initiation, elongation and termination. They are actually made up of amino acids.

These assisting factors enter and exit during different stages of translation. No assisting factors have been found throughout the process unlike ribosomes.