Biology Quiz 12/12

DNA Structure & Replication

DNA

Deoxyribonucleic Acid

What is DNA Responsible for?

Transmitting genetic information from one generation to the next (heredity)

nucleotides

monomers that repeat to make DNA molecules

What are the 3 parts of a nucleotide?

5-carbon sugar, phosphate group, nitrogenous base

Name the 4 Nitrogenous bases

Guanine, Adenine, Cytosine, Thymine

Which base pairs with Guanine?

Cytosine

Which base pairs with Adenine?

Thymine

Which base pairs with Cytosine?

Guanine

Which base pairs with Thymine?

Adenine

DNA is often described as a “______”

ladder

What kind of bonds hold base pairs together?

Hydrogen bonds

replication

the duplicating of DNA within a cell

What happens during DNA replication?

DNA splits into two strands, then two new complimentary strands are produced following base pairing rules

semi-conservative replication

each molecule of DNA has one old strand and one new strand

Where does DNA replication take place?

Nucleus

Helicase

“unzips” a segment of DNA by breaking the hydrogen bonds between the complimentary strands

single-strand binding proteins

stabilize the two complimentary strands

DNA Polymerase III

adds nucleotides continuously to the leading strand

RNA Primase

Lays down a primer for DNA polymerase III to start from

which strand has to be synthesized in fragments? What are these fragments called?

lagging strand; Okazaki fragments

DNA Ligase

closes gaps between segments of the lagging strand

DNA Polymerase I

removes RNA primer and adds DNA nucleotides

what type of bonds hold sugars/phosphates and sugars/bases together?

Phosphodiester bonds

purines

adenine, guanine

pyrimidines

thymine, cytosine