DNA/Genetics

Who discovered the nucleotides?

Hershey and Chase

Who discovered the way DNA looks?

Watson and Crick

Name the nucleotides for DNA and then RNA

Adenine, Thymine, Guanine, and Cytosine

For RNA, replace Thymine with Uracil

What is the purpose of DNA?

Provides genetic code for a trait

What is semiconservative replication?

In semiconservative replication, the original two strands of the double helix serve as templates for new strands of DNA. When replication is complete, two double-stranded DNA molecules will be present. Each will consist of one original template strand and one newly synthesized strand that is complementary to the template.

What are the enzymes that help semi conservative replication?

DNA Helicase, DNA Primase, DNA Polymerase, and DNA Ligase

What is DNA Helicase?

"Unzips" the DNA
--Breaks the hydrogen bonds between the nucleotides

What is DNA Primase

"Highlighter"
--Highlights an area of where the new half should be built on

What is DNA Polymerase?

--"Builder"
--an enzyme that joins individual nucleotides to produce a new strand of DNA
--builds in a 5' to 3' direction ALWAYS
--proofreads

What is DNA Ligase

"The glue"
--Fills gaps left in the lagging strand
--Fills with OKAZAKI fragments

What is the leading strand?

The strand where replication moves towards the replication (follows helicase)

What is the lagging strand?

The strand where DNA replication moves away from the replication (away from helicase)

what is topoisomerase?

Keeps the DNA from winding together too much

What does 5' and 3' mean?

5' is the end of DNA with a phosphate, and 3' is the end with a deoxyribose sugar

What is DNA transcription?

process of writing a copy of a DNA template into mRNA

What is RNA Polymerase?

an enzyme that binds to DNA during transcription and separates or unwinds the DNA strands.

What are the sub-steps to DNA trancription

Initiation, Elongation, and termination

What is Initiation?

RNA polymerase binds to promoter

What is a promoter?

binding site for RNA polymerase

What is elongation?

Codes along the new strand

What is termination?

Signals that the build is done and mRNA is made which goes to the Ribosome and its made into a protien

What is translation?

The transition of DNA from a nucleus to mRNA and going to the ribosome

What is tRNA?

brings an amino acid from the cytoplasm

What is a codon?

a sequence of three nucleotides that together form a unit of genetic code in a DNA or RNA molecule.

What is a Codon Chart?

A chart of codon sequences that tells you what amino acid a codon sequence on the mRNA codes for.

What are mutations in DNA

Change in DNA sequence
- have diff consequences relating to the phenotype of the animal

What are the types of mutations

deletion, insertion, substitution, chromosomal mutations, and non disjunction

What is the substitution mutation

Replacement of a single nucleotide by another nucleotide

What is the insertation mutation?

a frameshift mutation, moves all nucleotides from the right of the new nucleotide

What is the deletion mutation?

frameshift mutation, one nucleotide is taken away from a gene or DNA sequence

what is Chromosomal mutations

changes in the chromosomes where parts of the chromosomes are broken and lost during mitosis

what is non disjuction?

When an egg or sperm cell has to many or to less amounts of chromosomes

What is gene expression?

the process by which DNA directs the synthesis of proteins

What is a operon?

a group of genes that operate together

What is a lac operon?

--A collection of genes that are important in coding for enzymes that metabolize lactose.
--If code is being used than it created a enzyme, if not than it doesn't create an enzyme
--if lactose is not present, it doesnt create an enzyme
--saves energy if no enzyme is made

What is eukaryotic regulation?

Exons and Introns

what is an exon?

An expressed sequence of DNA; codes for a protein

what is an intron

non-coding region of DNA, helps prevent mistakes