IB biology: topic 2/7: DNA VS RNA

what does DNA stand for?

Deoxyribonucleic acid

what is DNA?

the genetic material in all living organisms

what does the DNA code do?

tells the cell what to do and what proteins to make.

where is DNA found in eukaryotes?

DNA is found mainly in the nucleus but there is also some in chloroplasts and mitochondria.

where is DNA found in prokaryotes?

DNA is not enclosed in a membranous envelope

what is RNA?

a single-stranded nucleic acid molecule

what is the function of RNA?

mostly involved in synthesising proteins

what is the role of mRNA?

transfers genetic information to the rest of the cell and later to make proteins

how are ribosomes formed?

from RNA and proteins

what is the function of nucleic acid?

carry the cell's genetic code (instructions for the function of the cell).

what are DNA and RNA made up of?

nucleotides

what are examples of nucleic acids?

DNA and RNA

what are nucleic acids made up of?

polynucleotides

what is an important role of nucleic acids?

important for passing on information from generation to generation.

what type of bonds connect the two strands of DNA?

hydrogen bonds

what is a DNA nucleotide made up of?

a deoxyribose sugar, a phosphate group and an organic base (A,C,G,T)

what is a RNA nucleotide made up of?

a ribose sugar, a phosphate group and an organic base (A,C,G,U)

what type of reaction joins bonds between the two nucleotides?

a condensation reaction (between sugar of one nucleotide and phosphate group of different nucleotide)

how many hydrogen bonds does A-T form?

2

how many hydrogen bonds does C-G form?

3

what are the two forms of nucleic acids?

pyrimidines and purines

what are pyrimidines?

single-ringed molecules - cytosine, thymine and uracil

what are purines?

double-ringed molecules - guanine and adenine

what is the difference between uracil and thymine?

thymine is present in DNA, while uracil is used in RNA

what is the monomer of DNA and RNA?

nucleotides

what are polynucleotides?

nucleotides joined together to make up nucleic acids (e.g DNA or RNA)

what is the structure of nucleotides?

formed from a pentose sugar, a nitrogen-containing organic base and a phosphate group.

what is the structure of deoxyribose?

the carbon 2 hydroxyl group loses its oxygen, leaving a hydrogen atom

what is the structure of ribose?

the carbon 2 hydroxyl group keeps its oxygen, leaving an OH group

what is the genome?

the complete set of genes in an individual's DNA.

what do the genes in the genome do?

encode the different proteins a cell needs

what is the proteome?

the full range of proteins an individual can produce.

what is a codon?

a specific sequence of **three** bases
The order of the bases on the DNA tells us the order for combining amino acids to create particular proteins.

how is an amino acid encoded?

a specific sequence of three bases (codon) encodes a specific amino acid

what is RNA usually made up of?

single strand of ribonucleotides (ribose, phosphate group and base)

what does RNA stand for?

ribonucleic acid

what does a codon code for?

one amino acid

what are key features of tRNA?

has an anticodon which is complementary to the mRNA codon

what type of nucelotide is uracil? (RNA)

pyrimidine