Lecture 2 Flashcards
Atom
Has nucleus with protons and neutrons, electrons orbiting
Atomic mass
Number of protons plus neutrons
Atomic #
Of protons
Covalent bonds
Bonds formed by sharing valence electrons
Nonpolar
Electrons shared equally
Polar
Electrons shared unequally like in water
Ionic bonds
Electrons donated forming bond
Donor becomes positive and receiver negative
Strongest bonds for physiology
Covalent
Free ions
Created when ionic compounds dissociate in water an individual ions are surrounded by water, key to many physiological processes
Hydrogen bonds
Weak bond between 2 polar molecules, based on charges
Between H atoms and N or O
Acid
Proton donor
Base
Proton acceptor
Buffer
Weak acid and base paired to resist H+ concentration changes; stabilizes pH of a solution
Buffer pair in human blood
Stabilizes blood pH, bicarbonate ion HCO3 - and carbonic acid H2CO3
Bicarbonate neutralizes excess acid by accepting protons
Carbonic acid neutralizes excess base by donating protons
Organic molecules
Contain carbon and hydrogen
4 types biomolecules
Carbohydrates, lipids, proteins, nucleotides
Carbohydrates
Carbon, hydrogen, oxygen in 1:2:1 ratio, sugars and starches, ose suffix
Monosaccharide
C6H12O6
Glucose, fructose, galactose
Sucrose
Disaccharide of glucose and fructose
Lactose
Disaccharide glucose and galactose
Glycogen
Polysaccharide of glucoses
Glycogen main purpose
To store glucose in cells in a way that prevents osmotic swelling
Condensation/ dehydration synthesis
Hydrogen atom is removed from one molecule and a hydroxyl group from another to form water
Small → big
Hydrolysis
Splitting of larger saccharides into smaller components by adding water
Big → small
Lipids
Mostly carbons and hydrogens, form chains/rings
5 lipids
Triglycerides, ketones, eicosanoids (prostaglandins), phospholipids, steroids
SKEPT
Triglycerides
One glycerol and three fatty acids
Glycerol
3-carbon alcohol
Fatty and
Long hydrocarbon chains with carbonyl (cooh) at one end
Saturated fatty acid
No double bonds, carbons maxed out on hydrogens
Unsaturated fatty acid
Double bonds, fewer hydrogens per carbon
Monounsaturated = more than 1 double bond
Ketone bodies
Free fatty acids in blood from triglyceride hydrolysis can be converted into these
Ketosis
Rapid fat breakdown from low carb diet or uncontrolled diabetes causes elevated ketone levels
Ketoacidosis
When ketone levels are high enough to lower pH
Can lead to coma or death
Phospholipid
Lipid containing a phosphate group with glycerol forming the back bone
Polar fatty acid (head) and nonpolar (tail)
Micelles
Spherical structure of phospholipids that transport nonpolar molecules in an aqueous environment
Surfactant
Type of phospholipid in lungs that decreases attraction between water molecules helping to prevent lung collapse
Steroids
3 six carbon rings, one five carbon, nonpolar
Most common steroid
Cholesterol, precursor to steroid hormones also used to make vitamin D and bile salts
Prostaglandins (eicosanoids)
Fatty acid with cyclic hydrocarbon group, communication between cells in the same organ
Blood vessel diameter, ovulation, contractions, clotting, etc.
Amino acid
Has an amino group, carbonyl group, and functional group
Amino acids
20
Peptide bond
Bond between adjacent amino acids; covalent
Secondary protein structure
Folding pattern, alpha helices, beta folds formed by h-bonds
Tertiary protein structure
3D shape based on interactions of r groups
Which level of structure dictates function
Tertiary 3D structure
Quaternary structure
Proteins containing more than one polypeptide chain
Quaternary structure examples
Hemoglobin (4) and insulin (2)
Protein functions
Structure, enzymes, antibodies, receptors, carriers
Nucleotide
Composed of 5 carbon sugar, a phosphate group, and a nitrogenous base
Pyrimidines
Carbon ring + nitrogen
Cytosine, thymine, uracil
Purines
2 carbon rings + ribose or deoxyribose
Guanine and adenine
C-G
3 H bonds
A-T
2 H bonds
3 RNA types
Messenger RNA, transfer RNA, ribosomal RNA
