Unit1:Biomolecules Flashcards
> 90% of the body’s mass consists of:
a. Oxygen
b. Carbon
c. Hydrogen
Cations
(lost an electron, positively charged)
: Sodium (Na+);
Potassium (K+); Calcium (Ca2+); Magnesium (Mg2+); Hydrogen (H+
Anions
(gained an electron, negatively charged): Chloride (Cl-);bicarbonate (HCO3-); Phosphate (PO42-), Sulfate (SO42-)
List Other major elements:
Nitrogen (N); Phosphorus (P); Sulfur (S)
list minor elements
: Iron (Fe); Iodine (I); Copper (Cu); Zinc (Zn), etc.
molecules
Atoms join together to form…..
Covalent Bonds
atoms share electrons
Ø Strong bonds that require energy to make or break
Ø Can form single, double and triple bonds depending on how many
electrons are shared.
- non polar, polar
Non-Polar Covalent Molecules
shared electrons are distributed evenly amongst
atoms, leading to all regions of the molecule having a neutral charge
are not very soluble in water (i.e. are hydrophobic not hydrophilic).
Ø E.g. O2, CO2, fatty acids, cholesterol (or any molecule composed mostly of
carbon and hydrogen atoms).
Polar Covalent Molecules
shared electrons are distributed unevenly (spend more time around a particular atom or part of the molecule)
Result: one region of the molecule has a partial negative charge (d-) and another region has a partial positive charge (d+).
Ø Molecules with polar covalent bonds are
soluble in water (i.e. are hydrophilic)
Ø E.g. water (H2O), glucose (C6H12O6)
Non-Covalent bonds
facilitate reversible reactions
- ionic
-VDWS
- h bonds
Ionic Bonds
atom to atom transfer of electron(s).
Ø The most polar bond (making them very soluble in water, i.e. hydrophilic)
Ø Transfer of electrons forms anions & cations.
Ø The two oppositely charged ions are attracted to one another (electrostatic attraction - like magnets, opposite charges attract and like charges repel).
Ø E.g. NaCl
Hydrogen Bonds
weak bond between hydrogen atom
and nearby oxygen, nitrogen or fluorine atom.
Ø E.g. attractive forces between individual water
molecules leading to surface tension.
Van der Waals Forces
– weak bond involving attraction
between electrons of one atom and the nucleus
(protons) of another atom.
Inorganic Molecules
usually lack carbon atoms
Ø E.g. water (H2O), salt (NaCl), hydrochloric acid (HCl)
List the exceptions of organic molecules
Ø There are some exceptions. The following are
inorganic molecules that contain carbon: carbonic
acid (H2CO3); Bicarbonate (HCO3), Carbon dioxide
(CO2), Carbon monoxide (CO).
Organic Molecules
molecules that contains
covalently bonded carbon atoms (often combined with H, O, N, P, or S). Includes all of the biomolecules
List the biomolecules
a. Carbohydrates
b. Lipids
c. Nucleic acids
d. Proteins
Carbohydrates
a. Consist of C, H, and O
b. General formula of CnH2nOn
Ø E.g.1: glucose (n=6); C6H12O6
Ø E.g.2: ribose found in RNA (n=5); C5H10O5
Ø Some exceptions: E.g.3: deoxyribose found in DNA = C5H10O
List some of the properties of carbs
i. Most are polar and therefore hydrophilic (soluble in water)
ii. Most abundant biomolecule in nature. Found in both plants
(cellulose & starch) and animals (chitin & glycogen)
Monomer
basic unit of structure
monosaccharides
1 sugar
- monomers of carbs
(glucose, fructose, galactose, ribose, deoxyribose)
Polymers
(formed by joining monomers together
disaccharides
are polymers
sucrose, maltose, lactose
polysaccharides
starch & glycogen)
What two monosaccharides form sucrose (table sugar)?
fructose and glc
What are some of the functions of carbs?
i. Energy for cells
Ø Glucose metabolism forms ATP (adenosinetriphosphate)
ii. Structural component of other biomolecules (DNA & RNA)
Ø E.g.1: DNA contains deoxyribose
Ø E.g.2: RNA contains ribose
iii. Structural component of cells – e.g. can be bound to lipids and proteins to form glycolipids and glycoproteins which have important roles in the structure and function of cell membranes.
Lipids
Consist of C, H, and O, but in a different ratio than carbohydrates (less oxygen); some have N and P
List some of the properties of lipids
Hydrophobic (insoluble in water)
list the different groups of lipids
- FA
- glycerides
- phospholipids
-sphingolipids - steroids
- eicosanoids
Fatty acids
Ø Long hydrocarbon chains with 8-28.carbon
Ø Has a carboxyl (-COOH) functional group (= acidic)
- can be saturated or unsaturated
Saturated
no double bonds between carbon atoms so forms a straight chain
Solid at room temperature.
E.g. palmitic acid (palm oil, butter, animal fats); stearic acid (butter, chocolate, lard); lauric acid (coconut oil).
Unsaturated
has double bonds between carbon atoms