Chapter 1 review test (copy)

How is a polymer formed from multiple monomers?

removal of -OH group and hydrogen atom

a triglyceride is a form of ____ composed of ____.

lipid; fatty acids and glycerol

What makes starch different from cellulose?

Cellulose forms long filaments, while starch is highly branched

Cholestrol is a precursor for

steroid hormones (sex hormones)

formation of a peptide bond also results in creation of what substance

water

allosteric sites are responsible for

regulating enzyme activity

which part of an animo acid has the greatest influence on the overall structure of a protein

the R group

2 main carbon containing molecules in organisms

carbohydrates and lipids

what property of water allows for H bonding?

polarity

how would enzyme function be affected if temperature in body increased

less efficient as shapes would warp

role of allosteric inhibitor

bind away from active site to change enzyme shape

coenzymes vs cofactors

coenzymes: organic molecules that assist an enzyme (vitamins)

cofactors: inorganic, usually metal, assist in catalysing reaction (minerals)

two changes that can cause enzyme to denature

temperature, pH, heavy metals

organic molecule vs inorganic + 2 examples of each

organic contains C, H (methane and ethane), inorganic doesn’t have C, (Ag, S)

identify monomer + type of reaction required to make it (protein, glycogen, RNA)

amino acids, glucose, nucleotides. condensation synthesis for all

ionic bond traits

ionic bonds results in transfer of electrons. tend to be hard but brittle, have high boiling and melting points

covalent bond traits

sharing of electrons between nuclei of 2 non metals. tend to be softer and have lower melting and boiling points.

molecular forces

forces of attraction that exist within and between molecules

2 types of molecular forces

intramolecular and intermolecular

which of the 2 types of molecular forces is stronger?

intramolecular forces are stronger than intermolecular forces

electronegativity (ENG)

measure of an atom’s ability to attract a shared pair of electrons

(generally) do nm have higher ENG than metals?

Yes, nonmetals have higher ENG than metals

Highest ENG

Fluorine

Two types of covalent bonds

polar covalent and non polar covalent

traits of pure npc bonds

equal sharing of electrons between atoms (atoms have same eng) forms between diatomic molecules

how do you get polar covalent bond and what does it result in

results from unequal sharing of electrons. there is a localised negative charge around one atom and a positive one around another

intermolecular forces in order from strongest to weakest

H bonding, dipole-dipole, London dispersion

traits of H bonding

• force of attraction between H atom of one molecule and a high ENG atom of another

• molecule is polar (H is slightly positive)

dipole dipole bond traits

force of attraction between molecules with permanent dipoles (polar molecules)

London dispersion force traits

• overs between all covalent molecules

• weak temporary attractive forces

• produced when instantaneous dipole in molecule induces dipole in another one

  • this results in slight attraction between molecules

hydrophobic interactions

• non polar molecules don’t form H bonds

• when mixed with polar molecules, np molecules clump together and are considered hydrophobic

why don’t oil and water mix

• partial charges on water attract pushing the oil (no partial charges) out of the way

what elements make up all biological macromolecules (almost)?

C H O N P S

Saturated vs unsaturated molecules

saturated molecules have only single bonds. unsaturated molecules have multiple bonds

isomers

compounds that have same formula but different structural arrangements

4 main types of macromolecules

• carbs

• lipids

• proteins

• nucleic acids

carbohydrate molecule composition

C + H2O (CH2O)

functional groups present in carbohydrates

carbonyl and hydroxyl

functions of carbohydrates

• sources of energy

• structural and connective tissue

• building materials

• cell markers (identification)

monosaccharides

• simple sugars

• distinguished by the # of atoms in chain (usually 3-7)

examples of monosaccharides

glucose, fructose, galactose

ring formation in carbs

monosaccharides with more than 5 carbon atoms form ring structures when dissolved in water

alpha and beta attachment in ring structures

depending if the OH group attaches from top or bottom, different structure is formed

• alpha (OH attaches below ring)

• beta (OH attaches above ring)

disaccharides

• joining two monosaccharides

• 2 carbon rings are joined together forming glycosidic bond

polysaccharides

• joined by glycosidic linkages

2 types of function of polysaccharides

storage :energy storage hydrolysed as needed

structural support: building materials for the cell

examples of energy storing polysaccharides

• starch, glycogen

examples of structural polysaccharides

• cellulose

• chitin

lipid composition (3 elements)

C H O

what macromolecule stores the most energy

lipids

functions of lipids

• long term energy storage

• protection against heat loss (insulation)

• major component of membranes (phospholipids)

• wax protects against water loss

• chemical messengers (hormones)

why are lipids well suited for long term energy storage

• contain many high energy CH bonds

• contain twice as much energy as carbs

types of lipids

• triglycerides

• phospholipids

• steroids

• waxes

triglycerides

• composed of 1 glycerol, 3 fatty acids

• saturated have only single bonds (solid at room temp)

• unsaturated have some multi bonds (liquid at room temp)

phospholipids

• major structural component of cell membranes

• one fatty acid is replaced w/ phosphate group

• have polar end and non polar end (amphipathic)

• forms bilayer in aqueous solutions

• long chain of fatty acids are hydrophobic and reject water

• phosphate is hydrophilic and aligns with water

steroids

• lipids derived from cholesterol

• formed from 4 fused rings (diff. attached functional group changes the molecules)

• act as hormones, important component of cell membrane and play role in cell signalling and metabolism

• cholesterol is natural component of cell membranes

• used by cells to make steroid hormones, vitamin D, bile salt

waxes

• solid at room temp

• coats surfaces to prevent water loss and offer physical protection

nucleic acids function

• storage of genetic information

• protein synthesis

• metabolism

2 types of nucleic acids + locations

• DNA: inside nucleus

• RNA: inside nucleus and cytoplasm

nucleic acid structure

• monomers are nucleotides

  • chain of these is called a strand

composition of nucleotides

1. pentose sugar, deoxyribose and ribose

2. phosphate

3. one of 5 nitrogenous bases (ACGTU)

nitrogenous base division

• nitrogenous bases are subdivided into purines (2 rings) and pyrimidines (one ring)

what are the purines and pyrimidines

• purines AG

• pyrimidines TCU

DNA and traits

• double stranded (held together by H bonds between complimentary bases)

• A bonds with T

• C bonds with G

RNA and traits (nitrogenous base)

• usually single stranded

• HAS URACIL INSTEAD OF THYMINE

nucleic acid bond

• phosphodiester linkage

• occurs between phosphate of one group and hydroxyl group on sugar of another base

• creates sugar phosphate backbone

protein structure (bonds, monomers, elemental composition)

• composed of CHON(S) sometimes S

• also called peptides/polypeptides

• monomer amino acid

all proteins are made of ___ amino acids

20

how many amino acids of 20 are considered essential

8

amino acid composition

contains dental C atom bonded to 4 groups

• Hydrogen

• Carboxyl

• Amine

• R group

All amino acids are somewhat polar (some can be more depending on R group)

bonds that make proteins

peptide bonds (aka amide bonds)

• forms between carboxyl of one amino acid and amino group of another

amino acid combinations

20 diff acids ^ length of amino acid chain

protein folding

• proteins are only functional when polypeptide folds into correct 3d shape

structures of proteins (first and second)

• polypeptide is primary protein structure (linear)

• secondary protein structure involves forming H bonds

  • alpha helix forms coil

  • beta pleated folds folded sheets

tertiary protein folding

• occurs to make active protein

• folds to make complex shape

• bonds are formed between functional groups between diff amino acids

• some are accomplished naturally, others created with assistance of molecular chaperones

forces that maintain protein structure

• H bonding

• London dispersion forces

• covalent bonds

• ion dipole forces

• hydrophobic effect

quaternary protein folding

• sometimes 2 or more tertiary proteins bind to form quaternary protein

• each end has one iron atom that binds to oxygen

protein denaturation

if exposed to sig. change in temp or pH, bonds which hold proteins in their shapes are broken

• once shape is gone, so is function

two main types of energy transfer reactions

exothermic: release energy from bonds (product molecules are smaller than reactants)

endothermic: energy is stored in bonds of molecules (products are larger than reactants)

activation energy + what happens if it is large

• energy required to begin any reaction

• if ae is large, reaction occurs slowly

enzymes

• special proteins that speed up or catalyse a reaction

• end in “ase”

• can be reused

• have specific shapes and work only for one exact reaction

enzyme substrate complex

enzyme binding to substrate forms this

how can enzyme lower activation energy

• orienting substrates correctly

• straining substrate bonds

• providing favourable microenvironment

• covalently bonding to substrate and making it more reactive

factors affecting enzyme activity

• temp (too low not flexible, too high, intermolecular forces are disrupted)

• pH and ions (can disrupt intermolecular forces)

• substrate concentration (more substrate → faster enzyme substrate will form)

types of enzyme inhibitors

competitive inhibitors and allosteric inhibitors

competitive inhibitors

compete with substrate to bind to active site of enzyme

allosteric inhibition

bind away from active site, causing enzyme shape to change

enzyme activators

molecules that bind to allosteric site on enzyme to keep it active or increase enzyme activity (basically opposite of inhibitor)

metabolism

sum of all chemical reactions that occur in living organism

2 types of metabolism + what they are

anabolism: reactions that build up molecules

catabolism: reactions that break down molecules

4 major reactions

1. condensation synthesis (aka dehydration synthesis)

2. hydrolysis

3. neutralization

4. redox

condensation reaction

• monomers make polymers

• water is produced

hydrolysis reactions

• breaks polymer into monomers

• water is added to reactants to break them up (water is also broken up in process)

neutralisation

• acids and bases react to form salt and water

buffers

molecules that react to minimise pH changes by donating or accepting H+ ions

• they exist as pairs of acids and bases

LEO goes GER

loss electrons oxidation, gain electrons reduction

what does the dual character of a phospholipid refer to?

• bilayer (one layer is hydrophobic and one is hydrophilic)

• essential to its function in living systems because it forms the basic structural framework of cell membranes

2 examples of steroids + function

• testosterone: regulate sexual function + aids in building bone and muscle mass

• oestrogen: regulate sexual function + increase storage of fat

why are two molecules affected in a redox reaction? why can’t one molecule just lose the electron and stay like that?

• electrons are highly reactive and cannot exist on their own or free in the cell

• this means it has to be accepted by another molecule