Anatomy Unit 2

Atom

Nucleus and the electron cloud

Atomic Number

Number of protons ( And number of electrons)

Mass Number

Number of protons + Number of Neutrons

Mass number - Atomic Number = ?

Number of Neutrons

Isotopes

Atoms of an element that contain different numbers of a neutrons ( C 14 and C12)

Radioisotopes

Isotopes that emit radiation ( Radioactive)

Chemical Bonds

Octet Rule = All atoms want to have 8 electrons in outer shell

Covalent Bonds

Electrons are shared between 2 atoms

Polar Covalent Bond

Bond where one atom has the shared electrons more of the time giving the atoms in the molecule a partial charge. ( Ex. Water)

Hydrogen Bonding gives water:

• High heat capacity

• Cohesion ( Sticks to itself)

• Adhesion ( Sticks to certain surfaces)

Ionic bonds

Electrons are stolen from one atom by the other. Resulting in opposite charges cause the atoms to be bonded together. ( Ex. Salt)

Dissociation of Water

H20 ←—→ H + plus OH-

In pure water [H+] =

10 ^-7 M

pH

the measure of hydrogen ions ( H+)

pH= -log [H+]

If pH is 6, [H+] = ?

= 10^-6

pH Scale

Going left of the pH scale increases H+ concentration

Acids

pH > 7

More H+ than OH- in solution

Bases

pH < 7

More OH- than H+

Electrolytes

Ionic compounds that conduct electricity when dissolved inh water

Solution

Solute dissolved in solvent

Buffers

Can neutralize small amounts of acid or base to prevent changes to pH

M = ?

M = Mol solute / L of solution

Decomposition Reaction

AB —-> A + B

• Catabolism: Breakdown of big molecules, releases energy

Synthesis Reaction

A + B ——> AB

• Anabolism: Synthesis of big molecules; requires energy

Exchange / Replacement / Displacement Reaction

AB + CD ——> AD + CB

A + BC ——> AC + B

Enerdgonic = Endothermic

Heat or energy is absorbed during the process

• Energy is stored in molecule

Exergonic= Exothermic

• Heart or energy is released during the process

• Energy is released from molecules

Reversible Reaction

Many reactions are reversible and exist in equilibrium

Catalysts

Speed up chemical reactions by lowering activation energy of the reaction

Carbons form bonds in the form of a…

Tetrahedron

4 Major Macromolecules

Carbohydrates, Lipids, Proteins, Nucleic Acides

Polymer

Large molecule with repeating subunits

Monomers

Building blocks of large molecules

Condensation reaction or Dehydration Synthesis

How monomers are linked together, a water is taken out

Hydrolysis

Breakdown of a macromolecule by adding a water molecule to certain bonds

Carbohydrates

( Sugars, simple and complex)

Monosaccharide

• Monomer

• 3-7 Carbons

• Triose, Tetrose, Pentose, Hexose ( Glucose) Heptose

Glucose

Hexose sugar, can be linear or ring structure; equilibrium

Dissacharide

2 monosaccharides linked together to form a polymer ( Sucrose)

Polysaccharide

Several monosaccharides linked together to form a polymer

3 Major Polysaccharides

Glycogen, Cellulose, Starch

Glycogen

• Animal version of Starch

• Branching glucose polysacch.

• Store energy f/ animals in liver and muscles

• Short term storage

Starch

How plants store energy

Cellulose

Makes up cell wall, examples are cotton, wood, paper ( high in fiber)

Lipids

• Not polymer

• Contain fatty acids

• Fats, oils, waves, steroids

Saturated fatty acid

No carbon to carbon double bond ( high in hydrogen, solid)

Unsaturated Fatty acid

Have some carbon to carbon double bonds ( Liquid, less hydrogens)

Carboxyl Group

Carbon double bonded to Oxygen, then an Oxygen and Hydrogen ion

* Lipids to know*

• Triglycerides= 3 fatty a’s + glycerol

• Phospholipids = 2 fatty a’s + glycerol + phosphate

• Steroids = Complex ring structures ( Act as hormones, cholesterol not hormone)

Amino acids

Building blocks for monomers, form polypeptides

Primary Structure

Sequence / order of aa’s

Secondary Structure

Hydrogen Bonding between aa’s. Either alpha-helix or beta-pleating

Tertiary Structure

Hydrogen Bonding and disulfide bridges result in folding of polypeptide chain

Quarternary Structur4e

Relationship between polypeptides in a protein

Functions of Proteins

Structural, Contractile, Transport, Buffer, Enzymes, hormones, Defense

How a protein folds

Negative or positive, polar or nonp, all affect how the protein folds

Nucleic acid chains are made up of

nucleotides

Nucleotide contains..

5 sugar carbon, phosphate and nitrogen base

ATP is

High energy bond, Adenine triphosphate