DNA and Proteins

Central Dogma

a theory stating that genetic information flows only in one direction, from DNA, to RNA, to protein, or RNA directly to protein

mRNA

stands for messenger RNA. It is a type of RNA that carries genetic information from the DNA in the cell nucleus to the ribosomes in the cytoplasm, where it is used to synthesize proteins.

rRNA

molecules carry the coding sequences for protein synthesis and are called transcripts

tRNA

molecules form the core of a cell's ribosomes (the structures in which protein synthesis takes place)

Transcription

the process where the information in a strand of DNA is copied into a new molecule of messenger RNA (mRNA) by RNA polymerase.

Where does transcription occur?

occurs in the nucleus of a eukaryotic cell or the cytoplasm of a prokaryotic cell.

Translation

the process where mRNA is decoded to produce a specific protein.

Where does translation occur?

It occurs in the ribosomes of a cell, specifically in the cytoplasm.

DNA (Deoxyribonucleic Acid)

Double-stranded

Contains deoxyribose sugar

Bases: A, T, C, G

Found in the nucleus

RNA (Ribonucleic Acid)

Single-stranded

Contains ribose sugar

Bases: A, U, C, G

Found in the nucleus and cytoplasm

mutation

a change in the DNA sequence that can lead to alterations in the protein produced, potentially affecting an organism's traits or functions.

Mutagen

a physical or chemical agent that changes an organism's DNA, increasing the frequency of mutations. Example: UV radiation from the sun can act as a mutagen, causing mutations in skin cells.

Types of mutations

frame shift (both insertion and deletion), gene duplication, translocation, inversion, silent mutation 

Codon

A sequence of three nucleotides on mRNA that codes for a specific amino acid during protein synthesis. Located on mRNA.

Anti-codon

A complementary sequence of three nucleotides on tRNA that pairs with the codon. Located on tRNA.

What are proteins?

large biomolecules

What are proteins made of?

amino acids

What is the bond that connects amino acids?

Amino acids are connected by peptide bonds to form proteins.

Bacteriophage

a virus that infects and replicates within bacteria. It consists of a protein coat and genetic material, either DNA or RNA.

Nucleotide

Building block of DNA/RNA, consisting of a sugar, phosphate, and nitrogenous base.

Double Helix

DNA structure with two intertwined strands.

Base Pairing Rules

A-T and G-C; complementary bases in DNA.

Replication

Process of copying DNA to produce an identical strand

DNA Polymerase

Enzyme that synthesizes DNA molecules.

RNA Polymerase

Enzyme that synthesizes RNA during transcription.

Stop Codon

Signals the end of protein synthesis on the mRNA.