what is the difference between RNA and DNA?

Question

i have a biology test in 2 days, i got a D- on my last one so i'm really trying to study.
i don't understand DNA and RNA. what is the difference and how/why does DNA become RNA or vice versa?
please try to explain it with simple terms because nothing else is helping

Answer 1

DNA is the master copy of the instructions for making proteins. DNA makes up the genes that are part of the chromosomes. The DNA is so important that it has to stay in the nucleus.

Proteins are made on the ribosomes that are loose in the cytoplasm or on ribosomes that are stuck on the rough endoplasmic reticulum. The problem is that the DNA has the instructions for this process, but the DNA has to stay in the nucleus and can't go out to the ribosomes to tell what to do.

That's where RNA comes into the process. mRNA (messenger RNA) is made in order to copy down the instructions for making a certain protein ... kind of like copying down a recipe from a cookbook that you can't take out of the library. The DNA opens up to get the gene copied, and the pieces of RNA are put together in a way that matches the DNA. When the mRNA is made, it breaks loose from the DNA and goes out of the nucleus to a ribosome. Meanwhile, the DNA closes back up and stays in the nucleus.

When the mRNA reaches a ribosome, tRNA starts bringing amino acids to put together in a chain that will make the protein. mRNA is "read" three letters or three bases at a time. Three bases make a codon. The first mRNA codon is always AUG. The only tRNA that will match AUG is UAC (A goes with U like AUstralia; C goes with G .. both round letters). So the tRNA with one end that says UAC brings its amino acid to start the protein. Then the next three letters on mRNA get matched by a different tRNA, and the second tRNA adds its amino acid to the chain. Eventually this process builds a protein.

What are the three big differences between DNA and RNA?
1. DNA has the sugar called deoxyribose; RNA has ribose.
2. DNA is double stranded; RNA is single stranded.
3. DNA has the bases A,T,C,G; RNA has the bases A,U,C,G. (Always match the round letters together. Do you see how C and G are both started by making a rounded shape? Always match C and G.)

Ask other questions if you have them.

Answer 2

Deoxyribonucleic acid (DNA) is a nucleic acid that contains the genetic instructions used in the development and functioning of all known living organisms and some viruses. The main role of DNA molecules is the long-term storage of information. Ribonucleic acid (RNA) is a type of molecule that consists of a long chain of nucleotide units. Each nucleotide consists of a nitrogenous base, a ribose sugar, and a phosphate. RNA is very similar to DNA, but differs in a few important structural details: in the cell, RNA is usually single-stranded, while DNA is usually double-stranded; RNA nucleotides contain ribose while DNA contains deoxyribose (a type of ribose that lacks one oxygen atom); and RNA has the base uracil rather than thymine that is present in DNA.

Answer 3

RNA is ribonucleic acid and DNA is Deoxyribonucleic acid. RNA is a type of nucleic acid that consists of nucleotid monomers with ribose sugar and nitrogenous bases adenine(A), cytosine(C), guanine(G), and uracil(U). Thry are normally single starands and function in protein synthesis. DNA is a double stranded helix like shaped nucleic acid molecule capable of replicating and determining the inherited stucture of the cell's proteins.