DNA, Genes and Chromosomes Flashcards
What is the function of DNA and RNA
Both carry information.
DNA is genetic info
RNA carries genetic info from DNA to ribosomes.
What is the structure of a nucleotide?
Consists of phosphate, pentose (5-Carbon) Sugar and Organic Base (containing Nitrogen).
What are the differences in structure between a DNA nucleotide and RNA nucleotide?
DNA nucleotide has a deoxyribose sugar.
RNA nucleotide has a ribose sugar.
DNA has bases guanine, cytosine, adenine and THYMINE.
RNA has bases guanine, cytosine, adenine and URACIL.
How do two nucleotides join together?
A condensation reaction forms a phosphodiester bond between the nucleotides.
How do two nucleotides join together?
A condensation reaction which forms phosphodiester bonds. This requires energy from ATP.
What are ribosomes made of?
Two sub-units. rRNA and proteins.
What are the differences in DNA between eukaryotes and prokaryotes (+ mitochondria + chloroplasts)?
Eukaryotes = long, linear, associated with histones
Prokaryotes = Short, circular, not associated with proteins
Define gene.
A gene is a sequence of bases of DNA that code for a polypeptide or functional RNA (rRNA and tRNA).
List the 4 different bonds in a DNA molecule and where they are found.
- Phosphodiester bonds between phosphate of one nucleotide and sugar on second nucleotide.
- Glycosidic bond between sugar and base of nucleotide.
- Ester bond between phosphate and sugar of one nucleotide.
- Hydrogen bonds between complementary bases of two nucleotides.
What is the genetic code?
The order of bases on DNA.
Define codon.
Triplet of bases (3) that codes for an amino acid.
What is the locus?
The location of a gene on a chromosome.
What are introns?
Non-coding sections of DNA.
What are exons?
Coding sections of DNA.
How many amino acids are there?
20
