Chapter 2 Flashcards
Atomic number
number of protons (bottom)
atomic mass
mass of protons + mass of neutrons (top)
isotopes
atoms of same element that differ in neutrons
Radioactive isotopes
decay spontaneously giving off energy
atom used in carbon dating
C14
what are ions
elements that have a different number of electrons than it normally does
Ionic Bonds
- nonmetal and metal elements bond
- complete transfer of e-
Hydrogen bond
form between hydrogen and electronegative atom
Hydrophilic substances
- polar molecules
- form hydrogen bonds
Properties given to water from hydrogen bonds
- surface tension
- moderates temp
- ice is less dense than water
- universal solvent
covalent bonds
-sharing of electrons
- two non-metal elements
monosaccharides
simple sugars/ basic unit
Disaccharides
2 monosaccharides linked via a covalent bond
oligosaccharides
2-10 monosaccharides linked via a glycosidic bond
polysaccharides
polymers consisting of chains of >10 monosaccharide/ disaccharide units
Condensation forming a glycosidic bond
water is expelled taking a monosaccharide to a disaccharide
hydrolysis forming a glycosidic bond
water is consumed by taking a disaccharide to a monosaccharide
water-insoluble compounds, soluble in organic solvents
lipids
what kind of bonds make up fatty acids?
amphipathic bonds which means they have hydrophilic (polar) AND hydrophobic (non-polar ) bonds
How to tell if a fatty acid is unsaturated
shaped like the end of an arrow
how to tell if a fatty acid is saturated
shaped like a straight line
hydrophobic effect
minimize contact with hydrophobic molecules
what makes up cell membranes
phospholipids
how do you read amino acids?
from the amino end to the carboxyl group
building blocks of nucleic acids
sugar, phosphate, and a base
Which molecule is more stable, DNA or RNA?
DNA
