Exam 1 Study Guide Review

strength order of bonds (strongest to weakest)

ionic, covalent, hydrogen, Van der Waals

ionic bond

transfer of valence electrons between atoms; forms a salt

covalent bond

sharing of valence electrons by two atoms

molecule

consist of two or more atoms held together by covalent bonds (single, double or triple); smallest units of compounds that retains the characteristics of the said compound

nonpolar covalent bond

equal sharing of valence electrons; usually between atoms of the same element or two elements with similar electronegativities

polar covalent bond

unequal sharing of valence electrons

electronegativity

an atom’s strength of attraction/pull on the valence electrons

hydrogen bond

the non-covalent attraction between a hydrogen and an electronegative atom when the hydrogen atom has a partial positive charge

hydrogen bond example

the hydrogen (partial positive) of one H2O molecule will be attracted to the oxygen (partial negative) of another molecule

Van der Waals interaction

ever-changing regions of positive and negative charge that enable all atoms and molecules to stick to one another

the 4 properties of water

cohesive behavior, ability to moderate temperature, expansion upon freezing, universal solvent

cohesive behavior

the linking of like (water) molecules; results in surface tension

surface tension

measure of how difficult it is to stretch or break the surface of a liquida

adhesion

the clinging of one substance (water) to another; helps to counter gravity

ability to moderate temperature

water has a high specific heat capacity (it takes a lot of energy to change the temperature of one gram of water molecules by 1 degree C

example of water’s ability to moderate temperature

an elephant sprays water on itself to cool itself through vaporization

expansion upon freezing

water is less dense as a solid than as a liquid

universal solvent

water eventually dissolves all ions by forming a hydration shell around its atoms

hydration shell

a sphere of water molecules around a dissolve ion

functional groups

components of organic molecules that are most involved in chemical reactions

kinetic energy

energy of motionth

thermal energy

kinetic energy created by the random motion of atoms and molecules

temperature

a measure, in degrees, of the average kinetic energy (thermal energy) of the atoms and molecules in a substance

carbon structure properties

length, branching, double bond position, presence of rings

isomers

compounds with the same molecular formula but different structures and properties

structural isomers

different covalent arrangements of atoms

cis-trans (geometric) isomers

same covalent bonds that differ in their spatial arrangements

enantiomers

isomers that are mirror images of each other

essential elements in humans

carbon, hydrogen, oxygen, nitrogen (CHON)

trace essential elements

iron and iodine

pH=-log[H+]

more H+ atoms = lower pH

Which structures are affected by sickle cell anemia?

primary and quaternary

Which structures are affected by denaturation?

secondary, tertiary and quaternary

prokaryotic cells

smaller, have a nucleoid region, are unicellular, have circular DNA, have no membrane-bound organelles, have all seven characteristics of life

eukaryotic cells

larger, have a nucleus, have membrane-bound organelles, have linear DNA, can be unicellular or multicellular, have all seven characteristics of life

What are the similarities between prokaryotic and eukaryotic cells?

both are cells, and both have the seven characteristics of life

Thiomargarita magnifica

prokaryote with prokaryotic ribosomes and circular DNA, but contains an enclosed nucleus and vacuole (membrane-bound organelles); exclusion of the differences between prokaryotic and eukaryotic cells

advantages to compartmentalization

higher metabolism, more metabolic reactions, can undergo catabolic/anabolic reactions with many molecules, each compartment can have its own chemical/physical environment, allows division of labor amongst organelles

nucleic acids

polymers made of monomers called nucleotides; have a phosphate group, sugar (ribose), and a base group; held together by a phosphodieter bond

phosphodieter bond

between the phosphate group of one nucleic acid to the hydroxyl group of another nucleic acid

lipids

any of a large group of large biological molecules that mix poorly with water; have hydroxyl, carboxyl, and phosphate groups; held together by Ester linkages

Ester linkage/bond

between the hydroxyl of a glycerol and the carboxyl group of a fatty acid (lipids)

trans fats

unsaturated fatty acids that try to mimic the linear shape of a saturated fatty acid

amino acids

have an amino and carboxyl functional group; form peptide bonds

proteins

a biologically functional molecule consisting of one or more polypeptides folded and coiled into a specific 3-dimensional structure

8 proteins necessary for life

1. enzymatic

2. defensive

3. storage

4. transport

5. hormonal

6. receptor

7. contractile

8. structural

carbohydrates

have a carbonyl and hydroxyl group; normally ring-shaped; utilize a glycosidic linkage

glycosidic linkage

bond between hydroxyl groups (carbohydrates)

What is the difference between carbohydrates and lipids?

Carbohydrates store short-term energy and are more concentrated in plants whose seeds germinate quickly. Lipids store long-term energy because of their higher energy content, and are more concentrated in plants whose seeds undergo large stages of dormancy.

main functions of compartmentalization

• environmental interactions

• hereditary information transmission

• genetic information storage

• energy and matter transformation

example of enzymatic proteins

digestive enzymes

example of defensive proteins

antibodies

example of storage proteins

ovalbumin in eggs

example of transport proteins

hemoglobin in blood

example of hormonal proteins

insuline

example of receptor proteins

receptor-mediated endocytosis

examples of contractile proteins

actin and myosin

examples of structural proteins

keratin or collagen

examples of environmental interactions between compartments

plasma membranes and differing chemistries

examples of hereditary information transmission

turning genes into proteins

example of genetic information storage

storage of DNA in the nucleus

examples of energy and matter transformation

anabolism/catabolism, photosynthesis

What is the difference between starch and cellulose?

Starch has an alpha glycosidic linkage, which is digestible by humans. Cellulose has a beta glycosidic linkage, which is not digestible by humans.

smooth endoplasmic reticulum function

produces lipids and stores ions

rough endoplasmic reticulum function

studded with ribosomes; produces proteins

lysosome function

hydrolysis

hydrolysis

the chemical breakdown of a compound with water

golgi body function

folds proteins and makes vesicles for transport

golgi body structure

has a “receiving” side (trans face) and a “shipping” side (cis face)

Which linkages belong to which type of macromolecule?

• carbohydrates: glycosidic linkages

• lipids: ester linkages

• proteins: peptide bonds

• nucleic acids: phosphodieter linkages

primary structure of proteins

linear sequence of amino acids

secondary structure of proteins

folding patterns of the polypeptides (alpha-helix or beta-pleated sheets)

tertiary structure of proteins

3-dimensional shape of a single polypeptide chain; determined by interactions between amino acid side chains

quaternary structure of proteins

arrangement of multiple polypeptide chains within a protein complex

glycosidic linkages

linkage/bond for carbohydrates

ester linkages

linkage/bond for lipids

peptide bonds

linkage/bond for proteins

phosphodieter linkages

linkage/bond for nucleic acids