DNA replication

Question 1

DNA in prokaryotic cells

Answer 1

no nucleus, circular chromosomes located in a region of cytoplasm called the nucleoid, does not have histones

Question 2

DNA in eukaryotic cells

Answer 2

linear chromosomes found in the nucleus, in the form of chromatin and is coiled around proteins called histones

Question 2

DNA replication

Answer 2

occurs in the nucleus of eukaryotic cells and in the cytoplasm of prokaryotic cells

Question 2

evolution of cells

Answer 2

evidence that prokaryotic cells came before eukaryotic, as DNA found in chloroplast and mitochondria have circular chromosomes

Question 3

semi-conservative

Answer 3

DNA replication is described as this as the new DNA molecules both consist of one old and one new strand

Question 3

stage 1 of DNA replication

Answer 3

1. enzyme helicase breaks the weak hydrogen bonds between the bases

Question 4

stage 2 of DNA replication

Answer 4

2. free DNA nucleotides are attracted to the exposed complementary bases on the template strands. hydrogen bonds form between these bases

Question 5

stage 3 of DNA replication

Answer 5

the enzyme DNA polymerase joins the sugar and phosphate groups of adjacent nucleotides creating the sugar-phosphate backbone of the newly synthesized strand

Question 6

stage 4 of DNA replication

Answer 6

two new DNA molecules are formed

Question 8

leading and lagging strands

Answer 8

the leading strand runs in the 5’ to 3’ direction, the lagging strand runs in the 3’ to 5’ direction. DNA polymerase builds the new strand in the 3’ to 5’ direction, therefore the