Week 1 - chemicals building life Flashcards
water
- COHESION: of water via hydrogen bonds create SURFACE TENSION
- electronegativity creates a polar molecule w/ hydrogen bonding
isomers
structural: diff C skeleton
stereoisomers: same C skeleton
- differ in how groups attached
- enantiomers: D- sugars & L- AA
carbon
- can form up to 4 covalent bonds
- hydrocarbons: molecules of carbon & hydrogen
- nonpolar
- function groups: hydroxyl, carbonyl, carbooxyl, amino, sulfhydryl, phosphate, methyl
lipids
- insoluble → hydrophobic
- terpenes
- steroids
- prostaglandins
- in water, phospholipids form a BILAYER
lipids- triglycerides
- 1 glycerol + 3 fatty acids
- saturated: no double bond between C atoms → high melting point in ANIMALS
- unsaturated: 1 or more double bonds →low melting point in PLANTS
lipids - steroids
carbon skeleton is bent to form four fused rings
CHOLESTEROL: base steroid produces other steroids
proteins - functions
- enzyme catalysis
- defence
- transport
- support
- motion
- regulation
- storage
proteins - amino acid structure
- central carbon atom
- amino grtoup (NH2)
- carboxyl group (COOH)
- single hydrogen
- variable R group
proteins - peptides
- amino acids joined by dehydration - peptide bond
- long chains of AA spontaneously fold up
- FOLDING: congregation of hydrophobic AA in interior of protein & hydrophilic AA on ext
AA composition:
- hydrophobicity = solubility
- cysteine cont = stability
STRUCTURE DEFINES FUNCTION
proteins - levels of structure
- seq. of amino acids
- interaction of groups in peptide backbone: alpha helix & beta sheet
- folded, stabilised by forces →final level of structure: single PP chain
- arrangement of subunits → 2+ polypeptide
RNA
- ribose not deoxyribose
- uracil not thymine
- single polynucleotide strand
- specifies seq. of amino acids proteins
nucleic acid - nucleotide
Monomer: nucleotide → sugar + phosphate+ nitrogenous base
- PURINES: adenine, guanine
- PYRIMIDINES: thymine, cytosine, uracil
- nucleotides connected by PHOSPHODIESTER BONDS
DNA
encodes info
- AA seq. in protein
- base seq in DNA
double helix
- 2 polynucleotide strands
- hydrogenbonds
carbohydrates - function
- provide structure
- short & long term storage of energy
- part of nucleic acid backbone
- combine w/ proteins (glycoprotein)
- combine w/ lipids (glycolipids)
- involved in intracellular interactions between animal cells
carbohydrates - structure
MONOSACCHARIDE - simplest
DISACCHARIDE: transport or storage
POLYSACCHARIDE (dehydration) : storage: starch ; glycogen || struc supp: cellulose, chitin
- D-Glucose: most common → product of photosynthesis
- glycogen: in humans + broken down to release glucose when needed
amino
NH2
found in proteins, nucleic acids
sulfhydryl
SH
found in proteins
phosphate
PO4
found in nucleic acids
methyl
CH3
found in proteins
hyroxyl
-OH
found in: carbohydrates, proteins, nucleic acids, lipids
carbonyl
CO
found in: carbohydrates, nucleic acids
carboxyl
COOH
found in proteins, lipids
