Chapter 2: Basic Cellular Chemical Processes Flashcards
Discuss the (3) components of atoms and their charge.
Protons: Positive (+) charge
Neutrons: Neutral charge
Electrons: Negative (-) charge
Nucleus contains protons and neutrons.
Electrons are found in orbitals/shells outside nucleus.
- first shell contains 2
- second shell contains 8
Define atomic mass and atomic number.
Atomic Mass: sum of protons and neutrons in an atom
Atomic Number: number of protons in an atom
Define valence electrons.
Electrons found in the outer most shell
They participate in chemical rxns and form bonds
Define isotopes.
Different forms of the same atom.
Atomic # same, atomic mass is different b/c different number of neutrons
Discuss covalent bonds.
- Occur when atoms share valence electrons
2 types: nonpolar and polar - Nonpolar covalent bonds means e- are shared equally (no + or - poles)
- Strongest bond
- Polar colavent bonds means e- are shared UNEQUALLY
- 2nd strongest bond
Discuss ionic bonds.
- Occurs when valence electrons are transferred from one atom to another
- Forms charged atoms
- Weakest type of bond
- Cation (+ charge) and Anion (- charge)
- Hydrophilic/Hydrophobic (hydration spheres concept)
Discuss Hydrogen bonds.
- Hydrogen forms polar bond with another atom and takes on slight + charge making it attracted to nearby - charged atoms.
- IE: Hydrogen bonds form between adjacent H20’s and create surface tension
Discuss Acids, Bases, and pH.
Acid: proton donor (release H+ in soln)
Base: proton acceptor (accepts H+ in soln)
pH: symbol of H+ concentration in soln
- Scale of 0 to 14
- Acid: pH less than 7
- Base: pH greater than 7
- Pure H20 has neutral pH: 7
Discuss buffers and the bicarbonate buffer system in blood.
- Buffers: molecules that slow changes in pH by either combining with or releasing H+’s
Bicardbonate buffer system in blood:
H20 + CO2 H2CO3 H+ + HCO3-
Rxn can go in either direction depending on amt of H+
Discuss blood pH.
Normal Range: 7.35 - 7.45
- Maintained by buffering run
If blood pH drops below 7.35 = Acidosis
If blood pH rises above 7.45 = Alkalosis
Discuss organic molecules.
Organic molecules are those that contain Carbon!
- Carbon: 4 valence e-
- Bonds covalently to fill outer shell to 8 e-
Discuss carbohydrates and the 3 types.
Organic molecules containing Carbon, Hydrogen, and Oxygen in ratio 1:2:1 -> C(n)H(2n)O(n)
- Monosaccharides (simple sugars)
- i.e. glucose, fructose - Disaccharides (2 monosacchrides joined)
- i.e. Sucrose = glucose + fructose - Polysaccharides (many monosaccharides joined)
- i.e. starch and glycogen which are storage molecules for glucose
Discuss dehydration synthesis.
- Splitting water of 2 monosacchrides
- An H+ and OH- are removed producing water and the remaining parts of the monosaccharide bond together
Discuss hydrolysis.
- Reverse of dehydration synthesis
- H20 is split into H+ and OH- and each is added to a monosarccharide
- So you’re putting water back in and getting 2 molecules back
Discuss lipids.
- Insoluable in water
- can be saturated (bad for heart) of unsaturated (good for heart)
- Phospholipids 2 parts:
1. Phosphate part: round head, polar/hydrophilic (water loving)
2. Lipid part: tails, nonpolar/hydrophobic (hates water)