Lecture 1 Fundamentals

Pyrimidines- with single ring structures

Thymine and cytosine

Purines- with double ring structures

Adenine and guanine

Chargraff’s rule

The amount of adenine in DNA corresponds to the amount of amount of thymine and the amount of cytosine corresponds to the amount of guanine

Complementary strand is created from the 

parent DNA strand

5’ - NNNN- 3’

Lagging Strand Template

3’ - NNNN - 5’

Leading Strand Template

Hybridization

Formation of hydrogen bonds between two complementary strands of DNA

Antiparallel

two complementary single-stranded

nucleic acids oriented so that when hydrogen-bonded

together through complementary bases, the 5 ′ end of

one molecule is next to the 3 ′ end of the other

DNA polymerase

Enzyme responsible for the polymerization of the nucleotide chains

Primase

The base that is provided by another enzyme that gives a hydroxyl group to start the DNA replication process

Helicase

enzyme that unwinds and untangles DNA

Ligase

Enzyme that closes that nick that is opened by the DNA polymerase

Okazaki fragments

small fragments of replicated DNA that occur so that both strands of DNA can be replicated at the replication fork

Endonucleases

breaks the sugar phosphate backbone of DNA

Restriction enzymes

Endonucleases that recognize specific base sequences and break or restrict the DNA polymer at the sugar-phosphate backbone

the most often used Restriction Enzyme in laboratories is…

Type 2

Explain Type 2 Restriction enzymes

They recognize symmetrical DNA sequences and cut the sugar phosphate backbone in different ways, leaving no single strands at the cut site (blunt ends) or 5’ or 3’ overhanging single stranded ends

Single strand ends are … that can hybridize with complementary overhangs

Sticky

What enzyme puts the fragments back together after the restriction enzyme has the cut them apart?

DNA Ligase

What is the term for an efficient mode of transportation for the transfer of genes from one cell to another?

Plasmids

Plasmids are the source of particular phenotypes of …

multiple drug resistant bacteria

RNA has … sugars on its single stranded backbone

ribose

What is the difference between the sugar deoxyribose and ribose?

Ribose has an additional hydroxyl group than deoxyribose, making DNA more stable due to its lack of an oxygen atom 

Messenger RNA (mRNA)

conveys genetic information from DNA to the ribosome

Ribosomal RNA (rRNA)

The RNA component of the ribosome. It is the largest component of cellular RNA

Transfer RNA (tRNA)

Carries specific amino acids and aids in decoding the mRNA

Heteronuclear RNA (hnRNA)

Pre-messenger RNA that has not been processed

Small nuclear RNA (snRNA)

Plays role in processing hnRNA

Double stranded RNA (dsRNA)

Plays role in gene silencing

Micro RNA

Functions in RNA silencing and post-transcriptional regulation of gene expression

Which of the three types of RNA polymerases is responsible for the synthesis of mRNA?

RNA polymerase II

Copying of one strand of DNA into RNA is a process catalyzed by 

RNA polymerase

mRNA carries the information in DNA to the… where it is translated into a protein

ribosomes

3 phases of RNA transcription

Initiation, Elongation, and Termination

NucleoSIDES

Nitrogen base bound to unphosphorylated sugar (base + sugar) ie A,C,G,T

NucleoTIDES

Nitrogen base bound to phosphorylated sugar (base + phosphate + sugar) ie ATP

RNA transcription: Initiation

Alleles

Different forms of genes

Phenotype

A term applied to the visible expression of a trait or characteristic of an individual

Heterozygote

Term used to describe an individual having different copies of a gene that govern the expression of a trait

A gene that is always expressed is said to be

Dominant

Who is noted as the father of genetics?

Mendel

The place on a chromosome where a given gene is located:

locus

Organisms having two sets of chromosomes (one paternal and the other maternal) are said to be…

diploid

DNA replication is said to be…

semiconservative

Semiconservative

a term used to describe DNA replication where one strand is conserved and serves as a template for a new strand, resulting in a new double helix comprising one parent and one daughter strand

Which base is unique to RNA?

UracilT

The process by which genetic information from DNA to RNA is

Transcription

The process by which the information from the genetic code is converted into protein is

Translation

What are the pyrimidines?

Thymine, Cytosine, and Uracil

What are the purines?

Guanine and Adenosine (think GA is pure even if that is for sure not true)

What are these enzymes a part of:

• DNA primase

• DNA helicase

• DNA polymerase

• DNA ligase

DNA replisome

Is RNA Polymerase a part of the DNA replisome?

Nope