Cell Biol Chapter 1 outline
ADVANCED CELL BIOLOGY (BIOL 312) outline, Fall semester 2000
Chapter 1: Cells and their Molecules
I. Introduction to cells
A) Cell history
1) Robert Hooke = cells
2) Anton van Leeuwenhoek = animalcules
3) Louis Pasteur - spontaneous generation disproved
4) development of cell theory
a) Theodor Schwann
b) Matthias Schleiden
c) Rudolph Virchow
B) Cell Theory
1) cells are fundamental units of structure and function
2) all life forms are composed of cells
3) cells arise from preexisting cells
C) Classical Biochemistry and Genetics
1) Eduard Buchner - isolated enzymes from yeast
2) Emil Fisher - amino acids joined by peptide bonds
3) genetic break throughs
a) Gregor Mendel
b) Walter Sutton
c) Thomas Hunt Morgan
d) Barbara McClintock
e) George Beadle and Edward Tatum
f) Fred Griffith
g) Oswald Avery, Colin MacLeod, and MacLyn McCarty
h) Alfred Hershey and Martha Chase
D) Molecular Biology
1) James Watson and Francis Crick
E) Modern Cell Biology
1) cytology
2) biochemistry
3) genetics
II. Properties of Cells
A) Cell types
1) prokaryotes
2) eukaryotes
3) archaebacteria
B) Cell components
- cell membrane
- cell wall
- endoplasmic reticulum
- Golgi
- lysosomes
- peroxisomes
- vacules
- nucleus
- ribosomes
- mitochondria
- chloroplasts
- cytoskeleton
C) Limitations on cell size
1) diffusion
2) surface area to volume ratio
3) self assimilation
D) Means to overcome these limitations
1) cytoplasmic streaming
2) active transport
3) compartmentalization
4) microvilli
E) Viruses
- obligate intracellular parasites
- size
- basic structure
- shapes
- viral replication
- retroviruses
- cancer
III. Molecular composition of life
A) Basic chemistry
- Elements
- naturally occuring
- CHONPS
- covalent bond strength
B) Chemical Bonds
1) covalent bonds
a) nonpolar
b) polar (dipole)
2) non covalent bonds (interactions)
a) hydrogen bonds
b) ionic bonds
c) Van der Waals interactions
d) hydrophobic interactions
amphipathic molecules = of both kinds
IV. Water and pH
A) polarity of water - results in unique properties of water
1) cohesiveness
2) high heat capacity
3) high heat of vaporization
4) expands when freezes
5) excellent solvent
B) water as a solvent
amount of solvent expressed as moles/liter or molarity (M)
1M = FW in grams/liter
C) dissociation of water
1) pH
pH = -log[H+]
2) zwitterions (e.g. amino acids at pH=7)
3) buffers and pK
pH = pKa + log [A-]/[HA]
when [A-] = [HA]; pH = pKa
a) titration curves
Molecules and Macromolecules (see handout for functional groups)
I. Proteins
A) Functions
1) enzymes
2) transport
3) storage and nutrient
4) movement and contraction
5) structure
6) defense (antibodies)
7) regulation - hormones (some), receptors
8) control of gene expression
B) amino acids
1) general structure
2) as zwitterions
pH1 pH7 pH12 NH3+ NH3+ NH2 COOH COO- COO- (pK a amino group ~ 9.5, pK a carboxyl group ~ 2)
3) L and D isomers
4) groups of amino acids
a) nonpolar - hydrophobic
b) polar, uncharged
c) polar, charged = basic or acidic
5) charges on R groups
C) Peptide bonds
1) planar
2) phi and psi angles about the a carbon
D) Levels of protein structure
1) 1º structure = sequence of amino acids
a) protein sequencing
2) 2º structure = shape over short stretches
a) a helix
b) ß pleated sheet
Domains and motifs
3) 3º structure = shape of the polypeptide chain
4) 4º structure = combined shape of multiple subunits
5) experiments with ribonuclease - Anfinsen
E) additional aspects of proteins
1) post-translational modification
2) glycoproteins
3) lipoproteins
4) nucleoproteins
II. Nucleic acids
A) monomeric units = nucleotides
1) nitrogenous bases
2) pentose
3) phosphate
4) nomenclature
B) polymers = RNA and DNA
1) 5' vs. 3'
C) DNA structure
1) molar ratio of A, T, G, C (Chargaff's rules)
2) X-ray crystallography data
3) complimentary base pairing
4) Watson and Crick's double helix = antiparallel
5) forms of DNA
a) B form = Watson - Crick model = right handed, 10 residues/turn
b) A form = right handed, 11 residues/turn
c) Z DNA = left handed, 12 residues/turn
6) denaturation and renaturation of DNA
a) DNA melting curve
D) higher levels of DNA structure
1) linear vs. circular
2) single vs. double stranded
3) supercoiled
E) RNA (usually single stranded but frequently folds back on itself)
1) types
a) messenger ~ 10%
b) ribosomal ~ 75%
c) transfer ~ 15%
III. Lipids
A) fatty acids = CH3(CH2)nCOOH
1) saturated vs. unsaturated
B) neutral fats (triglycerides or triacylglycerols)
1) saturated = solid at room temp
2) unsaturated = liquid at room temp
C) phospholipids
1) derivatives of phospholipids (e.g. phosphatidyl choline)
2) micelles, liposomes, and bilayers
D) sphingolipids
1) cerebrosides = glycolipids
a) gangliosides (e.g. GM2)
2) sphingomyelin
E) steroids
1) steroid hormones
2) vitamin D
3) cholesterol
IV. Carbohydrates
A) functions
1) structural
2) energy reserves
B) monosaccharides
1) polyhydroxy aldehydes and ketones
2) CnH2nOn with n generally between 3-7
3) glucose
4) modifications e.g. sialic acid
C) disaccharides
1) maltose
2) sucrose
3) lactose
D) polysaccharides
1) structural = cellulose, mannan, chitin, cartilage proteoglycans
a) cellulose
b) cartilage proteoglycans = hyaluronic acid, keratin sulfate, chondroitin sulfate
2) storage
a) amylose
b) amylopectin
c) glycogen