Chapter 2: Introductory Biochemistry

Anatomy and Physiology

Chemistry Elements – cannot be broken down into

simpler form Chemical symbol – represented with letters

(first always capital and second is small)

Atoms – smallest unit of matter Protons Neutrons electrons

Atomic mass = mass of nucleus (protons + neutrons)

Atomic number =number of protons Number of electrons = # of protons Number of neutrons = atomic mass - #

protons

19F9

55Mn25

32S16

40Ca20

27Al13

Math Monkey MomentHow many protons, neutrons and electrons are in each atom?

Protons Neutrons Electrons

Be

Na

Ca

Electron shells – electrons move in layers around the nucleus 2 electrons in shell closest to nucleus 8 electrons in the next shell

Ions – atoms that give up or gain electrons when bonding to another atom become positive or negative (charge). i.e. Ca2+ or K-

Molecule – 2 or more atoms share electrons

Compound – 2 or more different types of atoms bonded together. H2O and C6H12O6 are compounds and moleculesO2 and N2 are molecules not compounds

Chemical Reactions Occurs when bonds are broken and

reformed Reactants Products Law of conservation of matter

Count the atoms in H2O and C6H12O6

C6H12O6 + 6O2 6CO2 + 6 H2O

Chemical energy - Energy stored in chemical bonds and is a form of potential energy Anabolic reactions build substances and

generally require energy which is then stored in their chemical bonds. i.e. glycogen

Catabolic reactions break down substances and release energy. i.e. fat catabolism

ATP – adenosine triphosphate is the compound of energy used for the work of cells in living organisms

Chemical Bonds Valence shell – outer electron shell and electrons

involved with bonding to other atoms. Ionic bonds – atom gains or loses electrons; metal

bonds to a nonmetal (see periodic table)

Cation – positively charged ionAnion – negatively charged ionElectrolytes – ionic compound that breaks apart into cations and anions when dissolved

Covalent bonds – atoms share electrons in their valence shell

(nonmetals only) Most common bonds in body Carbon can form 4 bonds

Hydrogen bonds – forms when hydrogen atoms with a partial positive charge bond with a partial negative atom.Weaker bondReason for properties of water

Vocabulary Cards

Anabolic

Catabolic

Cation

anion

Ionic bond

Covalent bond

Hydrogen

bond

Inorganic Compounds Organic – carbon containing compounds

(except CO2)

Inorganic – all others including CO2

Water is most important and abundant inorganic compound in living systems. 5 properties Excellent solvent

Solutes that are polar (slightly charged) are hydrophilic and dissolve in water.

Solutes that are nonpolar are hydrophobic and do not dissolve in water.

Participates in chemical reactions Absorbs and releases heat slowly –

helps moderate changes in body temp.

Requires a lot of heat to change from liquid to gas

Serves as a lubricant: major component of mucus

Acids and bases Acids break apart or dissociate into

one or more hydrogen ions (H+) Bases break apart or dissociate into

one or more hydroxide ions (OH-) Salt dissociates into cations and anions

that are neither H+ nor OH-

pH Scale of 0-14 Below 7, greater H+ than OH-

and are acids Above 7, greater OH- than H+

and are bases 7 is neutral

10-1

10-4

10-8

10-14

Buffers Living systems are very sensitive to

changes in pH Buffer systems keep pH stable by giving

up H+ or OH- depending on what is needed

Blood pH is 7.35-7.45. Lethal is 6.8 and 7.8

i.e. bicarbonate buffer systemCO2 + H2O H2CO3 HCO3

- + H+

Organic compounds Most common elements of living

organisms: CHNOPS Made of monomers or building blocks

Monomers combined by dehydration synthesis reaction and water is lost.

Monomers break apart by hydrolysis and water required.

Vocabulary CardsOrganic

Inorganic

Dehydration synthesis

HydrolysisBufferpH

Organic Macromolecules Carbohydrates Lipids Proteins Nucleic Acids

Carbohydrates Monomer: monosaccharides Monomer components: C, H, O (2:1H-

C)

Types

Monosaccharides Disaccharides Polysaccharides(starch) Function: energy

Proteins Monomers: amino acids Monomer components:

amino group (-NH2), carboxyl group (-COOH), and side chain (R group)

C, H, O, N, S

Types: Peptide polypeptide

Function(s): multiple Varies depending on type Generally responsible for structure

of body cells

Enzymes Proteins that are catalysts to

speed up chemical reactions without being altered themselves.

Act as a lock and key Substrate is the key and binds

to the active site on the enzyme Enzyme is the lock or binding

site Form enzyme-substrate

complex

Lipids Monomers: fatty acids and glycerol Monomer components: C, H, O (H-O not

2:1)

Types: Triglyceride

Saturatedunsaturated

Steroids phospholipids

Function(s) Triglycerides – energy Steroids – hormones Phospholipids-membranes

Nucleic Acids Monomer: nucleotide Monomer components: sugar, phosphate,

nitrogen base

Types DNA: deoxyribonucleic acid

Adenine, thymine, cytosine, and guanineDouble strandedhelix

RNA: ribonucleic acidAdenine, uracil, cytosine, and guanineSingle stranded

Function: hereditary information

Vocabulary Cards

Enzyme Lipid Carbohydrate Protein Nucleic acid

ANY QUESTIONS?