Genetics Day 2 Vocab and Topics

Nucleic Acids

type of macromolecule/polymer made up/ chain of nucleotides; two main examples are DNA and RNA

Deoxyribose

5 carbon sugar with only H group attached at 2’ position

Ribose

5 carbon sugar with hydroxyl OH group attached at 2’ position

Purines

Nitrogenous bases: Adenine and Guanine; 2 rings; both in DNA and RNA

Pyridines

Nitrogenous bases: Cytosine, Thymine (DNA), and Uracil (RNA); 1 ring; T only in DNA and U only in RNA

Nucleotide

building blocks of monomers/nucleic acids; made up of a phosphate group, sugar molecules, and nitrogenous bases; purine and pyrimidine nucleotides

Phosphodiester Bonds

covalent bond that connects nucleotides; nucleotides add on 3’, phosphate always on 5’

Double Helix

shape of double stranded DNA

Anti Parallel

strands in double helix run in opposite directions; 5’ to 3’ strand pairs w/ 3’ to 5’

Complementary

Adenine pairs w/ Thymine; Cytosine pairs w/ Guanine

Semiconservative

new DNA strands have one OG strand and one new strand

Bidirectional

start in one place and go both ways

Semidiscontinous

lagging strand is made in pieces while leading strand is made in one piece

Proofreading

DNA polymerases can detect and remove mismatched bases during synthesis

Origin of Replication

where replication starts

Leading Strand

strand made in one piece

Lagging Strand

strand made in omazaki fragments

Okazaki fragments

short DNA segments on lagging strands

Helicase

enzyme that unwinds DNA double helix right at replication fork; breaks complementary bases apart

Single Stranded Binding Proteins

stabilize single strands (keeps fork open by preventing rebinding/hairpins)

Primase/Primers

primase makes RNA primer that tells polymerase where to start

DNA Polymerase III

adds dNTPS/makes new DNA (binds to primer)

dNTPs

any nucleotide

DNA Polymerase I

replaces RNA primers w/ DNA

Ligase

links/joins fragments

Replisome

large complex of proteins involved in DNA replication

Proofreading Activity

part of DNA polymerase that error corrects

Transcription

RNA Polymerase

what carries out transcription

Coding (Sense) Strand

identical to mRNA

Template (Antisense) Strand

opposite of mRNA read in 3’ to 5” direction

Promoter

what RNA polymerase binds to; DNA sequence that signals start of gene

TATA Box

DNA sequence inside promoter; recognized during initation

General Transcription Factors (GTFs)

protein recruiters at promoter of enzyme

RNA Polymerase II

makes pre-initiation complex w/ GTFs to start transcription

pre-mRNA

mRNA before 3 steps it needs to leave; mRNA in cell

mRNA Capping

nucleotide added to 5’ (start) to provide stability, assist exit, and help translate

mRNA Polyadenylation

Poly A tail; added to 3’ (end) for protection against degradation

Ribozymes

catalytic enzymes (give power to start splicing); snRNAs in spliceosomes

mRNA Splicing

removal of non coding enzymes + joining coding sequences

Exons

what its kept/ coding sequences that are joined tg (get EXported and translated)

Introns

whats thrown away and degrade; dont get translated

Spliceosome

what links exons and cuts out introns

Side Chains/ R-Groups

chemical groups attached to amino acids that give specific properties

Peptide Bonds

what holds amino acids tg in chain

Polypeptide

chain of amino acids held tg by peptide bonds

Primary Structure

linear; N to C

Secondary Structure

alpha and beta sheets held tg by h bonds

Tertiary Structure

3d shape of polypeptide made by interactions of side chains

Quaternary Structure

when multiple proteins combine to give protein function

Conformation

final 3d shape of protein

Genetic Code

rules/box to follow to turn nucleotide sequence into amino acids

Codon

basic unit of genetic code; 3 baess

Stop Codon

do not signal for amino acids; signal to stop translation

Reading Frames

3 ways to read mRNA sequence each give different amino acid sequence

transfer RNAs (tRNAs)

what can acc read mRNA sequence and collect correct amino acids to make polypeptide chain

anticodon

Wobble Base Pairing

Aminoacyl-tRNA Synthetases

ribosomal RNA (rRNA)

Exit Site

Peptidyl Site

Aminoacyl Site

mRNA-binding Site

ribosome binding site

start codon

Release factors