Biology 110 Exam 1 Purdue University

biggest to smallest things

Eukaryotic - prokaryotic - viruses - macromolecules - atoms

Elements

made of one type of atom

Ion

atoms with net electric charge

atoms tend to lose/gain electrons

Covalent Bonding

atoms SHARE electrons

stronger than ionic bonds

C makes 4 covalent bonds

Nonpolar covalent bond

electrons shared equally

Polar covalent bond

electrons shared unequally

Electronegativity

how strongly an atom attracts an electron

determines whether a covalent bond will be polar/nonpolar

nonpolar electronegativity

0.0-0.4; similar electronegativity

polar electronegativity

>0.4; different electronegativity

Important things about water

1. water is a reactant

2. Means of transport (resistant to temp change, plant transport, blood)

3. Temperature buffer

Water bonds

covalent; polar

Hydrogen bond

the attraction between a partial positive H and another partial negatively charged element

-between atoms

-can bond with up to 4 other atoms

-allows water to be liquid at room temperature

Polar molecules

Soluble

Nonpolar molecules

not soluable

Hydrophylic

Water-loving (polar and soluble)

Hydrophobic

"Water-fearing"; pertaining to nonpolar molecules (or parts of molecules) that do not dissolve in water.

Bronsted-lowry acid

donated protons (H+)

Bronsted-lowry base

accepts protons (H+)

pH is low

concentration of H+ is high

Macromolecules

big molecules held by covalent bonds

-defined by their monomers

Polymers

made up of monomers

Monomers

repeating units that serve as the building blocks of a polymer

classes of macromolecules

1. Carbohydrates

2. Lipids

3. Proteins

4. Nucleic Acids

Condensation reactions

link monomers together to form polymer (water molecules product of reaction)

Hydrolysis

water is used as reactant to break macromolecules to back into individual monomers

Carbohydrate Monomers

simple sugars, MONOSACCHARIDES; ex. glucose fructose

Carbohydrate Polymers

POLYSACCHARIDES; ex. starch, cellulose, glycogen

Cellulose

Polymer of glucose; in plant cell walls

Gives shape and structure to plant cells

Cannot digest

Ex. buildings, heat, tools, cotton

Beta Glucose

Monomer of glucose; monomers held together by Beta linkages

Animals don't have enxymes to break B-linkages

Cellulose Digestion

Cows - harbor microorganisms that can break down cellulose

Endosymbiotic relationship

Starch/Glycogen

polymers of a-glucose monomers held together by a-linkages

storage molecules for a-glucose

Starch

storage molecules for a-glucose in vacuoles for energy; only plants make this

Glycogen

storage molecule for a-glucose; only animals make this

In liver, muscles, and other tissues for energy

Branching glycogen

highly branched

more free ends -> broken down more quickly by multiple enzymes for energy

Cellulose branching

Lined structure for support and structure

Starch branching

medium amount of branching

Simple Lysine

Simple aspartic acid

Protein Monomers

Amino Acids

Polymers of Amino Acids

proteins

Protein Functions

1. enzymes

2. Signaling molecules (horomones/neurotransmitters)

3. Surface receptores (cell signaling)

4. Movement: motor proteins

5. Structural

Amino Acids

building blocks of proteins

bonds between amino acids

peptide bonds

1st amino acid

Amino-terminus

Last amino acid

Carboxyl-terminus

Nucleic acid monomers

Nucleotides

Nucleic acid polymers

DNA and RNA

Nucleic acid function

DNA: stores genetic information

RNA: expression of genetic information

Nucleotide makeup

5 carbon sugar, phosphate group, nitrogenous base

DNA makeup

H+ attached to the hydrogarbon: deoxyribose

RNA makeup

OH- attached to hydrocarbon: ribose

RNA nucleotide

held together by phosphodiester bonds

1 phosphate backbone

nitrogenous base

DNA nucleotide

held together by phosphodiester bonds

2 phosphate backbones

hydrogen bonding between base pairs

Lipids

Energy-rich organic compounds, such as fats, oils, and waxes, that are made of carbon, hydrogen, and oxygen.

Triglyceride

consist of a glycerol molecule with three fatty acid chains

forms of stored energy for plants/animals

PHospholipids

modified triglycerides containing a phosphate group

form cell membranes

Triglyceride glycerol

3 carbon molecules that is the backbone of triglycerides

esterbonds

Triglyceride fatty acid

long hydrocarbon chains with a carboxylic attached

esterbonds

Saturated fatty acid

all C-C single bonds (long straight chains) (saturated with hydrogens)

Unsaturated fatty acid

C-C double bonds -> leads to kinds in the chain (bent)

Saturated at room temp

FA tend to pack well: solids (fats)

Unsaturated at room temp

FA tend not to pack well: liquid (oils)

Phospholipid monomer

1 glycerol, 2 fatty acids, 1 phosphate group

Amphipathic

molecule with both hydrophilic and hydrophobic properties (phospholipids)

Micelle

lipid molecules that arrange themselves in a spherical form in aqueous solutions

phospholipid bilayer

A double layer of phospholipids that makes up plasma and organelle membranes.