Prep for Cell/Mol Biology

Molecular biology

How the biological molecules (DNA, RNA, protein, etc.) interact

Cell biology

How cells are organized, communicate, and respond to stimuli

Deoxyribonucleic acid (DNA)

Holds genetic info for cells

DNA replication allows new DNA to be made from pre-existing DNA

Double helix

The spiral-staircase shape of a DNA molecule

Nucleotide

The basic unit of DNA

Contains a phosphate, sugar, and nitrogenous base

Base pairing

Corresponding bases are aligned between the DNA double strand.

• A binds to T, T binds to A

• C binds to G, G binds to C

Chromosome

Long DNA piece carrying genetic info for thousands of genes

DNA replication

Process that copies DNA for cell growth

Is semi-conservative: a pre-existing strand serves as the template for a new strand of DNA

RNA (ribonucleic acid)

A functional version of genetic information

Transcription

A process that makes RNA based on a DNA template

RNA polymerase

An enzyme that transcribes RNA based on a DNA template

Promoter

Gene expression is coordinated by transcription factors binding to gene promoters.

mRNA (messenger RNA)

Contains information to make a protein

tRNA (transfer RNA)

Brings correct amino acids to the ribosome

Proteins

Long strings of amino acids that do functions in a cell or for a cell

Amino acid

Ribosome

Cellular structure made of proteins and rRNA.

Ribosome translate proteins from information in mRNA

• Use mRNA information to put AAs together to make a protein

Translation

Uses mRNA to make proteins

Open reading frame

Prokaryote vs. eukaryote

Cell membrane

Cytoplasm vs. cytosol

Organelle

Nucleus

Location of DNA storage. Is double membraned.

• Nucleoplasm is the inside of the nucleus

• Nucleolus is the part of nucleoplasm that makes ribosome component

Rough ER

Is studded with ribosomes

Processes membrane proteins and secreted proteins

Vesicle

Transports cargo of proteins between organelles

E.g., ER to Golgi apparatus via vesicles

Golgi apparatus

Matures proteins

Proteasome

Endosome

Lysosome

Small, membrane-bound sac inside animal cells.

Contains strong digestive enzymes that break down waste, old cell parts, and harmful bacteria.

Endocytosis

Histone

Protein that winds DNA to make it compact; compacts DNA into heterochromatin

• Heterochromatin: very compact, not many expressed genes

• Euchromatin: more open/less compact, more expressed genes

Chromatin

Transcription factor

Gene Expression