Bio 12.2 and 12.3

Replication fork

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Nucleotides

3 parts: a simple sugar, a phosphate group, & a nitrogenous base. Nucleotides join together by dehydration synthesis - this forms strong covalent bonds between them

Purines

A and G are double-ring purines.

Telomerase

Adds short, repeated DNA sequences to telomeres, lengthening the chromosomes slightly and making it less likely that important gene sequences will be lost from the telomeres during replication.

Helicase

DNA helicase enzyme unwinds and unzips the double helix. Part of Stage 1: Unwinding

DNA ligase

DNA ligase forms a bond between the 3'OH of the growing strand and the 5' phosphate in front of it, joining the DNA fragments together.

DNA polymerase

DNA polymerase enzyme starts the process of adding new nucleotides to the new strand of DNA - it adds to the 3' end. Is part of Stage 2: Base pairing

DNA

Deoxyribonucleic acid is a type of nucleic acid. The information held in the molecules of DNA determine an organisms traits DNA holds all of the instructions for putting together proteins

Nucleic Acid

Nucleic acids are made of repeating units of nucleotides that make extremely long polymer strands

Okazaki Fragments

Okazaki Fragments are made when replicating the lagging strand away from the replication fork

Know the differences between DNA replication in prokaryotes and eukaryotes

Prokaryotic cells have no nucleus... DNA molecule is in cytoplasm Consists of a ring of DNA and associated proteins Eukaryotic cells have linear DNA organized into individual chromosomes 51 mil to 245 million base pairs long

RNA primase

RNA primase enzyme adds a short RNA primer sequence on each DNA strand

Describe the roles of DNA in living organisms. what DNA stands for, what types of cells and what cell structures contain DNA?

Storing information sequence of DNA nucleotides encodes information to make/control proteins Copying information Cells must make a complete copy of every one of its genes before the cell divides Transmitting information Genes are passed down from parent to offspring

Pyrimidines

T and C are single-ring pyrimidines. U?

Antiparallel

The 2 strands of DNA run in opposite directions Called "antiparallel".

adenine guanine thymine cytosine

The four nitrogenous bases

Covalent Bond

The nucleotides in a strand of DNA are joined by covalent bonds formed between their sugar and phosphate groups.

Deoxyribose

The sugar in DNA.

Telomere

The tips of chromosomes are known as telomeres.

Hydrogen Bond

Watson and Crick discovered that hydrogen bonds could form between certain nitrogenous bases, providing just enough force to hold the two DNA strands together. Hydrogen bonds are relatively weak chemical forces that allow the two strands of the helix to separate.