DNA And RNA Structure Flashcards
What does DNA stand for?
Deoxyribonucleic acid
What does RNA stand for?
Ribonucleic acid
What do DNA and RNA do?
In all living cells, DNA holds genetic information and RNA transfers genetic information from DNA to the ribosomes.
How are ribosomes formed?
Ribosomes are formed from RNA and proteins.
What are they made up of?
Both DNA and RNA are polymers of nucleotides. Each nucleotide is formed from a pentose, a nitrogen-containing organic base and a phosphate group
What are the components of DNA?
The components of a DNA nucleotide are deoxyribose, a phosphate group and one of the organic bases adenine, cytosine, guanine or thymine.
What are the components of RNA?
The components of an RNA nucleotide are ribose, a phosphate group and one of the organic bases adenine, cytosine, guanine or uracil.
How are phosphodiester bonds formed?
A condensation reaction between two nucleotides forms a phosphodiester bond.
What is the structure of DNA?
A DNA molecule is a double helix with two polynucleotide chains held together by hydrogen bonds between specific complementary base pairs.
What is the structure of RNA?
An RNA molecule is a relatively short polynucleotide chain.
Extra: Why did scientists question whether DNA did what it is said to do?
The relative simplicity of DNA led many scientists to doubt that it carried the genetic code.
How is DNA linked to evolution?
All organisms have similar DNA showing indirect evidence for evolution and all coming from similar organisms.
What are nucleotides?
Nucleotides are the subunits from which DNA is made. They are formed from a pentose sugar, a phosphate group and a nitrogen-containing base.
Who worked out the structure of DNA?
James Watson and Francis Crick worked out the structure of DNA in 1053.
What is a pentose?
A 5-carbon-sugar or deoxyribose
What is a phosphate group?
The phosphate group is a molecule containing one atom of phosphorus covalently bound to four oxygen residues, two of which may be expressed as a hydroxyl group. They are relatively reactive molecules that readily form phosphodiester bonds by the interaction with hydroxyl groups
What sort of bond holds the nucleotides (organic bases) together
Hydrogen bond holds together nucleotides in the centre of the structure
What is a hydrogen bond?
A chemical bond important in the three-dimensional structure of biological molecules. Hydrogen bonds break relatively easily.
How many polynucleotide strands are in DNA?
DNA has two strands and RNA has one.
What base pairs with thymine in DNA?
Adenine pairs with thymine in DNA
What base pairs with Cytosine in DNA?
Guanine pairs with cytosine in DNA
What base pairs with adenine in RNA?
Uracil pairs with adenine in RNA
What base pairs with Cytosine in RNA?
Guanine pairs with cytosine in RNA
What structure is DNA in:
A) Antiparallel strands
B) Opposite strands
C) Verticle Strands
DNA is in a double helix where the polynucleotide strands are antiparallel
