1.storage of genetic information

2.Reproduction and heredity

3. Transmission of genetic information 

1.Double helix

2. Two Polymers of nucleotides

3. Antiparallel

4. Sugar-phosphate backbone, bases toward center

5. Bases take on a stacked arrangement

6. Polymers held together by hydrogen bonding between bases

7. Two strands are complementary

The 5' end is the end where a free phosphate group is attatched to the number 5 carbon of the sugar.

The 3' end that has a free hydroxyl group attatched

Carbon 2'

DNA : has a hydrogen

RNA: hydroxyl

A hydrogen bonded to T

C hydrogen bonded to G

A hydrogen bonded to U

C hydrogen bonded to G

A 5 carbon sugar

a nitrogenous base

a phophate functional group

To control exchange of materials from the cytosol to the nucleaus

is a controlled pore

1. All Ribosomal RNA genes are contained here

2. All Ribosomal RNA transcription occurs here

3.Small and large ribosomal subunits are assembled here

a unit of DNA wrapped around a histone

information in DNA is used to make RNA in a process called transcription

Information in RNA is used to make proteins in a process called translation

Also called gene expression

How many base pairs are in a human haploid stage?

Diploid?

3 billion

6 billion

The long tail of adenine at the end of messenger RNA

To catalyze DNA directed RNA synthesis.

to read DNA and produce a complementary strand of RNA

1. transcription factors bind to promoter sequence

2. RNA polymerase comes in and bind to DNA at the transcription factors

3.transcription begins

The coding DNA sequence on a polymer of nucleotides that is the complement of the opposite strand

The template DNA sequence is strand RNA polymerase is reading and synthesizing a complementary strand

1. initiation which is assembling RNA polymerase at the promoter

2. elongation which is polymer synthesis of RNA

3.termination which is RNA polymerase recognizing the end of sythesis

A DNA template

Nucleotide triphosphates as substrates

in Eukaryotes it a protein called sigma factor

1 is 35 nucleotides upstream from the start site

the other is 10 nucleotides upstream from the start site

They are A-T rich

A to T bond is easiest to break which makes the splitting of DNA easier to accomplish

1. alot more DNA in eukaryotes

2. lots of intergenic regions in eukaryotes

3. eukaryotic RNA must be modified to become functional

4. RNA genes have unique promoters and have their own molecule of RNA polymerase to make them

prokaryotic DNA is mostly coding

Genes that are related are clustered together in operons

inter and intragenic DNA

Intra inside Genes

Inter are long strands

Requires a template

reads DNA 3' to 5'

sythesis of complementary strand occurs 5' to 3'

Use nucleoside triphosphate as substrates for energy

Prokaryotes- Funtional RNA molecule

Eukaryotes-non-functional RNA molecule

Transcription

Processing

Translation

Transcription 

Translation

codes for tRNA molecules and 5sRNA

What is snRNA and snoRNA?

(sn=Small nuclear sno=Small nucleolar)

1. important component of ribosomes

2. most abundant RNA molecule

49 ribosomal proteins complex with 28sRNA, 5.8sRNA, and 5sRNA

(s=svedburg units)

How do cells meet the high demand for ribosomal RNA?

3 ways.

1.Multiple Ribosomal RNA genes 

2. multiple rRNA genes

3.genes in cluster spread out across a chromosome

located in the nucleolus

come together when they bind to messenger RNA to make protein

1. removal of sequence from primary transcript

2. primary sequence will be chemically modifed

What is snoRNA made by?

What typ of RNA is snoRNA?

What is snoRNA called when binded to protein?

What does snoRNA's function?

Made by RNA pol 2

is a catalytic RNA also called a ribosyme 

When binded to protein called snoRNP

Responsible for cutting functional RNA from nonfunctional  RNA from a primary transcript

Transcription factor 3's recognizing and binding to tRNA promoter sequences

RNA pol 3 recognizing trascription factor 3's

What are the characteristics of tRNA?

2 characters

1.Have an amino acid binding site at the 3' hydroxyl

2.a sequence of nucleotides called the anticodon at the 5' end

RNA polymerase 2

1. recognization of promoter sequence TATA box in eukaryotes by transcription factors

2. delivery of RNA polymerase 2 to promoter sequence

3. activation of RNA polymerase 2 via covalent modification via poshporylation

through covalent modification of the 5' and 3' end

and removal of sequence

How is the 5' end chemically modified of mRNA primary transcript?

What is it function?

by adding a 5' cap that is a methylated guanosine monophosphate cap.

To protect the 5' end from digestion

How is the 3' end chemically modified?

What is its function?

Through removal of some sequence and the synthesis of a poly A tail by an enzyme after transcription.

To still be digested but only nonfunctional RNA

The phosphate functional group of  the nucleteotide is attatched to the 5' end of the primary trascript.

the terminal phosphate is cut off and the 5'carbons are linked together. guanosine then gets methylated

1. have a 5' cap

2. 3' poly A tail

UAA 

UAG

UGA

1. Initiation

2. Elongation

3. Termination

ribosomal RNA breaks the bond linking methione to its transfer RNA and catalyzes the peptide bond to the next amino acid. the amino acid then enter the exit site and the ribosome moves down the RNA one codon in a process called translocation.

1 2 and 3

1 is the E exit site

2 is the P peptidyl site

3 is the A amino Acyl site

The E site is the site where the transfer RNA is empty

The P site is the site that contains the growing polypeptide

The A site is where the tRNA carrying the next amino acid will bind

1. Triplet code

2. redundant code

3.64 codons but only 61 are coding for 20 amino acids

4.each amino acid is coded for by more than 1 codon except methionine

5. contains punctuation has start and stop codons

 6. nearly universal

 7. non-overlapping

1.recognition of an anticodon of tRNA 

2.Specific Amino acid

both at the active site

empty and uncharged

full and charged

base substitution

base addition or deletion

How is gene expression regulated?

(6 levels)

1.controlling accesibility of the DNA via methylation.

2. control of initiation

3. In eukaryotes control of RNA processing

4. control of half life of RNA

5.control of mRNA translation

6. control of post translational modifications

asexual reproduction

two cells with identical genetic code

What does DNA polymerase require?

Where does catalysis occur

A single strand of DNA as a template

The triphosphate forms of deoxynucleotides for energy

A 3' hydroxyl group to extend off of

catalysis is always 5' to 3'

only nucleotides to an already existing 3' hydroxyl group

it can not intiate strand synthesis

1. seperation of DNA strands

2. provision of 3' hydroxyl group by primase

3. DNA polymerase extends nucleotide triphosphates 5' to 3'

How many origins do eukaryotes have?

Prokaryotes?

Eukaryotes- many

Prokaryotes- 1

Primase will create a primer towards the replication fork then DNA polymerase will synthesize DNA away from the replication fork

then primase will jump towards the replication fork and synthsize another primer and DNA will synthesize DNA towards the primer intially created

Continuous synthesis of the leading strand

Discontinuous synthesis of the lagging strand

What does RNA polymerase catalyze? 

What does Primase Catalyze

RNA polymerase- RNA sythesis during transcription

Primase- RNA sythesis during replication