Macromolecules Flashcards
Macromolecules (Biological Molecules)
4 organic (carbon-based) compounds are the building blocks of all living things:
- carbohydrates
- lipids
- proteins
- nucleic acids
Functions:
- energy storage
- insulation
- growth
- repair
- communication
- transfer of hereditary information
Bigger molecule = more carbon bonds = more energy
Another name for macromolecules
Polymers - large molecules
What are polymers composed of?
Subunits called monomers
How are polymers joined?
Through an enzymatic reaction, where a water molecule is removed
Carbohydrates
(CH2O)n [n=# of carbon atoms]
- short and long term energy storage
- energy extracted through CELLULAR RESPIRATION
Monosaccharides
Simple Sugars: ring molecule with 3-7 C atoms
- in the foods we eat
- each containing 6 carbons are isomers
C6H12O6
Glucose, Galactose, Fructose
Alpha Glucose
Link to form glycogen and starch
OH at positions 1 and 4 are in the same position
Beta Glucose
Link to form cellulose
OH at positions 1 and 4 on opposite sides
Disaccharides
Double Sugars: 2 monsaccharides bonded together
C12H22O11 (CnH2On - H2O)
How are disaccharides formed?
What bond is formed?
Through a dehydration reaction
Glycosidic bond
Sucrose
In foods
Glucose + Fructose
Lactose
Dairy
Beta Galactose + Glucose = Alpha Lactose
Beta (1-4) glycosidic bond
Maltose
Starch
Glucose + Glucose
Lipids
- LONG TERM energy storage
- cushioning of organs (shock absorber)
- chemical messengers (HORMONES)
- insulation
- 1g lipid stores 2.25x more energy than 1g carbohydrates
Lipid polarity
Nonpolar - insoluble in polar solvent - hydrophobic
Cannot form H bonds with water
Triglyceride
Glycerol + 3 fatty acids
Function: energy
Ex. fats (butter)
Fats
Triglyceries made through an esterification reaction
Saturated fats
- contain the maximum number of C-H bonds
- solid at room temperature (i.e. animals fats, butter)
- RICHER ENERGY source
Unsaturated fats
- do not have the maximum number of C-H bonds (C=C)
- lower mp and bp
- liquids at room temperature (i.e. plant oil)
Phospholipids
Phosphate, fatty acids, phosphorilated alcohol
Function: (selective) barrier
Ex. cell membrane
Steroids
Ring structures
Function: hormones (messangers)
Ex. testosterone, estrogen, cholesterol
Terpenes
Amphiphilic
Function: pigment
Ex. chlorophyll
Waxes
Esters of fatty acids with long-chain alcohols
Function: protective and structural functions in plants and animals
Ex. beeswax
Nucleic Acids
- RNA [cope of DNA used to make proteins] and DNA (heredity)
- ATP (energy)
- NAD and FAD (electron carriers)
Monomer of nucleic acids
Nucleotide: sugar (pentose), phosphate, nitrogenous base
Proteins
- make up many cell structures
- numerous combinations = functional complexity
- delicate, can lose funtion if denatured (extreme pH or temp. or exposure to chemicals that nravel its structure)
Protein Polarity
If quarternary structure has polar groups facing outwards = soluble in water
If polar groups face inwards = does not dissolve in water
Protein Functions
- Enzymes
- Important structural components of living protoplasm (i.e. membranes, chromosomes)
- Hormones (chemical messengers)
- Plasma proteins in blood (clotting, fluid regulation buffer, antibodies
- Transport of oxygen as hemoglobin
- Contractile proteins in muscles
- Extracellular proteins provide support (i.e. cartilage, bone tendons, ligaments)
- Source of energy
Monomer of Proteins
Amino acids
Types of amino acids
20 types:
- 8 essential (not made in the body)
- 12 can be made in the body with the 8 essential amino acids
All organisms have the same amino acids, but different organization of proteins
R-group determmined the identity and unique chemical properties
How are proteins formed?
What bond is formed?
Through a dehydration reaction
Peptide bond
Protein Folding
4 Levels
Distinguished by degree of complexity in the polypetide chain
Primary Level
- sequence of amino acids (chain >50) makes up a specific protein polypetide chain
- determines ultimate shape or conformation
- peptode linkage of amino group (NH2) one amino acid + acid group (COOH) of next amino acid
Secondary Level
- regular localised folding patterns of the polypeptide chain
- forms alphahelix (extended outside) or beta sheets (antiparallel)
- chain interacts with neighbours through H-bonding between C=O and NH2 (5 amino acid units aparts)
Tertiary
- local 3D shape
- formed from interactions between various R-groups of amino acids
- folding of the coils or sheets
- hydrophilic and hydrophobic R groups
- H-bonding between distant amino acids
- disulphide bridges
- prosthetic groups
Quarternary
- assembly of 2+ folded chains associating to from a functional unit
- hed together by weak forces
- hydrophobic interactions
- H-bonding
- R group interaction
- Van Der Waal’s forces
Acids
Proton Donors
- soluble in watr
- good conductors
- litmus (turns red)
- phenolphthalein (colourless)
pH < 7 (low pH)
Ex.
organic - CH3COOH
inorganic - H2SO4, HCl
Bases
Proton Acceptors
- soluble in water
- good conductors
- litmus (turns blue)
pH > 7 (high pH)
Ex.
organic - amine (NH2)
inorganic - NaOH, NH3
Neutralization
acid + base = salt + water
(incomplete)
EX. NH2 + COOH-R = NH3 + COO(-)-R
Redox
Electron transfer reactions
EX. Fe + CuSO4 = FeSO4 + Cu
(e- are lost and gained)
Hydrolysis (hydration)
A water molecule is added
EX. dipeptide + H2O = 2 amino acids
Dehydration/condensation
A water molecule is removed
EX. esterification
3 fatty acids + glycerol = triglyceride + 3(H2O)
