DNA and RNA structure and function

Question 1

what 2 parts make up the human genome

Answer 1

1. nuclear genome
2. mitochondrial genome

Question 2

what is the nuclear genome comprised of

Answer 2

approximately 3.2 billion nucleotides divided into 24 linear molecules called chromosomes

Question 3

how many genes are in the nuclear genome

Answer 3

35000

Question 4

how many genes are in the mitochondrial genome

Answer 4

37

Question 5

What is the mitochondrial genome comprised of

Answer 5

a circular molecule of approximately 16569 nucleotides, with multiple copies in each mitochondria

Question 6

all cells have their own copy of the genome, what are the exceptions

Answer 6

cell types that lack nuclei e.g. red blood cells

Question 7

what are the vast majority of cells and what does this mean

Answer 7

diploid - means they carry two copies of each autosome and two sex chromosomes

Question 8

what do haploid cells contain and give an example

Answer 8

just 23 chromosomes - e.g. gametes

Question 9

what is a genome

Answer 9

a store of biological information

Question 10

what is genome expression

Answer 10

the accessing of information that requires the coordinated activity of enzymes and other proteins in a series of biochemical reactions - transcription and translation

Question 11

Who discovered DNA and when

Answer 11

Johann Miescher in 1869

Question 12

who discovered the inheritance patterns of genes and when

Answer 12

W.S Sutton in 1903 - led to the theory that genes are located on chromosomes

Question 13

What experiments suggested that DNA made genes

Answer 13

the latter experiments

Question 14

who proposed that DNA existed as a double-helix structure and when

Answer 14

James Watson and Francis Crick in 1951

Question 15

Name 6 key features of the double helix of DNA

Answer 15

1. Base pairing between two strands
2. Formation of hydrogen bonds
3. Complementary bases
4. Has major and minor grooves
5. Base stacking adds stability
6. Can exist in different forms

Question 16

What are the 3 main functions of DNA

Answer 16

1. It is the molecular basis for heredity
2. Contains the genetic information for protein synthesis
3. Genes dictate organisms physical and physiological traits

Question 17

Name 3 things about RNA structure

Answer 17

1. polynucleotide
2. contains phosphodiester bonds (less stable than DNAs’)
3. amount of RNA per cell varies with the size of the cell

Question 18

Name the 2 differences between RNA and DNA

Answer 18

1. RNA contains ribose not deoxy-ribose
2. RNA contains uracil not thymine

Question 19

Name the 5 different types of RNA and their functions

Answer 19

1. Messenger RNA - transcript of the protein coding gene
2. Ribosomal RNA - forms ribosomes
3. Transfer RNA - transports amino acids to ribosomes
4. Small nuclear RNA - used to modify rRNA molecules
5. Micro RNA/ Short interfering RNA - regualte expression