Cell Biology Chapter 2

Chemical Components of Cells

Chemistry for cells is very

regulated, temperature is exact, pH is exact

Cells continuously exchange things with

The environment

What are model organisms

The cells we study come from these

Escherichia Coli - MO

Type of bacteria, prokaryote, divides very fast, single circular DNA

Saccharomyces cerevisiae - MO

Yeast, simple and single-celled eukaryote

Arabidopsis thaliana

Wall cress, multi-celled eukaryote, easy to grow indoors, produces thousands of offspring in 8-10 weeks, model for plants

Drosophila melanogaster

Fruit fly, multi-celled eukaryote, know X and Y chromosome from this model, well mapped genome, best model for tracing cause and effect from DNA instructions to adult body structure, helped with alcohol studies on the brain (fetal alcohol syndrome)

Caenorhabditis elegans

Small worm, fully mapped brain, knows where all neurons are mapped, 959 body cells in adult body, used for addiction studies, eukaryote

Danio rerio

Zebra fish, eukaryote, used for developmental studies because they are see through for the first 1-2 weeks of life

Mus musculus

Mouse, eukaryote, has brain, has social relationships like humans, most genetically similar to humans, used to study gene function, can test how a drug impacts social interactions, gets some same diseases as humans

Homo sapiens

Humans, eukaryotes, 100% of prescription meds are tested on humans before being prescribed

What are the 2 major types of cell culture?

Primary cell lines + immortalized cell lines

Primary cell lines

Limited lifespan and stop dividing eventually, cells directly from live organisms, studies neurons, muscles, and how cells do their jobs

Immortalized cell lines

Example is cancer cells, they are able to divide forever, divide very quickly, doesn’t do cell jobs, able to use forever

Cells are made of

Atoms

Covalent bonds

Molecular marriage, very strong, difficult to form and difficult to break, occurs when 2 atoms share a pair of electrons

Ionic bonds

Molecular dating, readily forms and readily breaks, weak, transfer of electrons, 1 atom takes both electrons, examples: VDW, H-bonding, electrostatic attraction

All cellular life requires what to live?

Water: bent shape, H-bond between 2 H2O molecules

Hydrophilic

Water lover, dissolves easily in water, charged atoms or polar groups

Hydrophobic

Water hater, insoluble in water, uncharged atoms or nonpolar groups

Covalent bonds make the what of the cell?

Make the polymers

What are polymers?

Large molecule made of many smaller, repeating units called monomers linked together in a long chain

What are polymers connect together with?

Covalent Bonds

Polysaccharide

A type of polymer where sugar is its monomer, held together by glycosidic bonds which is a type of covalent bond

What is glycogen?

A polysaccharide made up of glucose units connected by glycosidic bonds.

What process releases sugar bonds

Hydrolysis

What process forms sugar bonds

Condensation

Lipids

A type of polymer where fatty acids are its monomer connected by ester bonds. This polymer is Amphipathic (hydrophilic and hydrophobic), so some parts of the polymer loves water (charged parts) and some hates it (long parts)

What are the 2 major types of fatty acids

Saturated and unsaturated

What are saturated fatty acids?

Single bonds only, solid at room temperature like coconut oil, packed super close

What are unsaturated fatty acids?

Double bonds only, liquid at room temperature like olive oil, more space between them

Lipids form what part of the cell?

The membrane

Proteins

A type of polymer where amino acids are its monomer and are connected by peptide bonds - type of covalent bond

Structure of amino acids?

Central carbon where on one side there is an amino group (NH2) and on the other there is a carboxyl group (COOH)

What is the backbone for all proteins?

N-C-C (starts at amino group and goes to central carbon, then carboxyl group)

Amino Acid properties

Some properties include: polar/charged, nonpolar/uncharged, acidic, basic, long chains, has rings. They can build any shape you want

Nucleic Acids

A type of polymer where nucleotides are its monomer where phosphodiester bond is the covalent bond that holds them together

What direction is the backbone of DNA or RNA and what it is made of?

Starting at 5’ and ending at 3’

Made of alternating sugar and phosphate groups derived from nucleotides, which link together to form nucleic acids

How do non-covalent bonds work?

Through protein-protein interaction and using the lock and key model