Which DNA polymerase has exonuclease activity?

Which DNA polymerase has exonuclease activity?

DNA Polymerase I possesses a 3´→5´ exonuclease activity or “proofreading” function, which lowers the error rate during DNA replication, and also contains a 5´→3´ exonuclease activity, which enables the enzyme to replace nucleotides in the growing strand of DNA by nick translation.

What are the two main actions of RNA polymerase?

RNA polymerases transcribe the information in DNA into RNA molecules that have a variety of functions, including messenger RNA, transfer RNA, ribosomal RNA (for protein synthesis), ribozymes (for catalysis), and microRNA (for regulation of gene expression).

Which RNA plays a role in transcription?

Messenger RNA

What is the difference between RNA and mRNA?

There are several different types of RNA. One type of RNA is known as mRNA, which stands for “messenger RNA.” mRNA is RNA that is read by ribosomes to build proteins. While all types of RNA are involved in building proteins, mRNA is the one that actually acts as the messenger.

What is the lifespan of RNA?

The experiments were repeated for some 50 different genes and showed that 80 percent of all RNAs undergo a rapid turnover, living less than 2 minutes and can be classified as short-lived. Only about 20 percent live longer, for about 5 to 10 minutes.

Which is the largest RNA?

m-RNA

Which is the smallest RNA?

tRNA

Which RNA has an Anticodon?

transfer RNA (tRNA)

What is difference between RNA and DNA?

There are two differences that distinguish DNA from RNA: (a) RNA contains the sugar ribose, while DNA contains the slightly different sugar deoxyribose (a type of ribose that lacks one oxygen atom), and (b) RNA has the nucleobase uracil while DNA contains thymine.

Is RNA a protein?

RNA as an enzyme Cech discovered that RNA can operate like a protein.

How many codons are needed for 1 amino acids?

The nucleotide triplet that encodes an amino acid is called a codon. Each group of three nucleotides encodes one amino acid. Since there are 64 combinations of 4 nucleotides taken three at a time and only 20 amino acids, the code is degenerate (more than one codon per amino acid, in most cases).

How many codons are needed for 4 amino acids?

We have 4 nucleotides A, T, G and C. So total number of combination for codons will be 4*4*4=64. Total there will be 64 codons for producing 20 amino acids, which are generally found in nature.

How many bases are needed for 4 amino acids?

Genetic experiments showed that an amino acid is in fact encoded by a group of three bases, or codon.