B - 1 - DNA and RNA Flashcards
What is the structure of a nucleotide?
- Phosphate
- Pentose sugar
- Nitrogen containing base
What is a sugar-phosphate backbone?
Alternating sugar and phosphate groups joined together in a polynucleotide chain
What is DNA?
Deoxyribonucleic acid - the molecule in cells that stores genetic information
What is RNA?
Ribonucleic acid - A type of nucleic acid, similar to DNA, but containing ribose instead of deoxyribose and uracil instead of thymine
What is one of the main functions of RNA?
To transfer genetic information from the DNA to the ribosomes.
What is the bond between two nucleotides called?
A phosphodiester bond
What is the structure of a DNA nucleotide?
- Phosphate
- Deoxyribose sugar
- Base (A,T,C or G)
Describe the structure of DNA
- Double helix
- Made up of polynucleotide strands
- They are very long and coiled up tightly so that lots if genetic information can fit into a small space in the cell nucleus
- Antiparallel strands
- Has a sugar phosphate backbone
What is complimentary base pairing?
Hydrogen bonding between specific pairs of bases on opposing polynucleotide strands
Describe the structure of an RNA nucleotide
- Ribose
- Phosphate group
- Bases (A, U, C or G)
Describe the structure of RNA
- Single polynucleotide strand
- Shorter than DNA
- Has a sugar phosphate backbone
How are ribosomes formed?
They are formed from RNA and proteins
Why did scientists in the 1800’s doubt that DNA carried the genetic code?
Because it has a relatively simple chemical composition
