Flashcards in Lecture 2 - atoms, bonds, and molecules Deck (23):
What is DNA used for?
identification and analysis
how are bacteria and viruses killed?
smallest particle of an element
-made up of electrons (e-), protons (p+), neutrons (n0)
what makes up a nucleus
protons and neutrons
made up of how many protons and neutrons
Carbon atomic number is 6 therefore it has 6 protons and 6 neutrons
what determines the different elements?
number of protons
carbon - 6
nitrogen - 7
two or more atoms (N2)
molecule formed from two or more different elements (C6H12O6)
what are compounds help together by?
sharing of electrons between atoms
*Strongest and most common
-formed between C, H, O, N, S and P
Complete transfer of electrons from one atom to another
-atoms separate into charged particles (ions)
1) cations (positive)
2) anions (negative)
what are electrolytes
ionic molecules that dissolve to form ions in solution
unequal sharing of electrons
-water: oxygen has more electrons than hydrogen (O= more negative)
-needed to be water soluble
-usually between H-O or H-N
-between dna base pairs
neutral molecules with equal electron sharing
-in cells they are composed of C-H
-fats and oils
repel water (non-polar)
hydrophilic and hydrophobic properties
Is DNA positive or negatively charged?
-why is this good?
-negatively charged (polar)
-water loves DNA because positive H on water is attracted to the negative part of DNA
amphipathic molecules (polar head (hydrophilic) and non-polar tail (hydrophobic))
when a component dissolved in water (acid) releases excess hydrogen ions (H+)
when a component dissolved in water releases excess hydroxide ions (OH-)