SBI4U - Metabolic Processes

Chemical reactions occurring in an organism

• Breaking down
• Larger molecules to smaller molecules
• Complex to simple
• Releases energy

• Building up
• Smaller molecules to bigger molecules
• Simple to complex
• Stores energy

Buffers resists significant changes in pH levels; keeps acid and bases in equillibrium

• Simple sugars
• Amino Acids
• Glycerol and fatty acids
• Nucleotides

• This reactions takes out an H from one unit and a OH from another unit, forming a water molecule. Monomers would be attached using dehydration synthesis. 
• Simple -> complex
• Energy is absorbed
• Anabolic
• Covalently bonded molecules is the result

Condensation/dehydration synthesis

• This reaction adds H2O, breaking it into H and OH and adding it to a polymor, breaking it down to monomers
• Complex -> simple
• Energy is released
• Catabolic
• Two unites are resulted

Carbohydrates

Monosaccharides

yas

Glycosidic linkages

Energy storing

Produced by plants through photosynthesis

Consists of amylose (straight chained a-glucose 1-4 linkage) and amylopectin (branched chain a-glucose polymer 1-4 and 1-6 linkages)

energy storing

“Animal starch”

• Excess glucose stored as glycogen in liver and
• muscles

When concentration of glucose is low, glycogen will be hydrolyzed

Stores small amounts and will be depleted in a day if not replenished

structure

Produced by plants

Straight chains of b glucose held together by B 1-4 glycosidic bonds H bonds

Most abundant organic compound

• Humans lack enzymes to break down B 1-4
• glycosidic bonds

b 1-4

N

Less OH bonds; less electronegative therefore not soluble in water but soluble in other nonpolar solutions

Ester linkages

• Saturated fats have only single bonds and solid bc straight hydrocarbons can stack nicely; unsaturated have double bonds and
• liquid bc bent so less Van der Waals attractions

Composed of glycerol molecule attached to two fatty acids and a highly polar phosphate group (head very polar and hydrophilic; tail nonpolar and hydrophobic)

four hydrocarbon rings

long chain fatty acids linked to alcohols or carbon rings

Proline; it makes a nonpolar covalent bond with its R group

20 R groups and the four levels of protein structure

Transport, Enzymes, Antibodies, Clotting, Hormones, Extra, Receptors, Structure

o    Sequence of amino acids directed by DNA when protein synthesis occurs

o    Protein synthesis is when amino acids are added to the growing chain

o    BONDING CHARACTERISTIC: covalent peptide bonds

o    Pleating or coiling of the primary structure due to H bonding between carboxyl and amino acids repeatedly

o    Results in a helix (e.g. keratin) or b pleated sheets (e.g. silk) (this occurs when two parts of the polypeptide chain lie parallel to one another, hydrogen bonding on the adjacent strand)

o    BONDING CHARACTERISTIC: hydrogen bonding

• o    3D shape of proteins occur due to various interactions
• (LD, DD, H-Bond) occurring in R groups :

• §  Hydrophobic reactions – directing themselves to
• core of proteins

§  H-bonds – between polar R-Groups

§  Ionic bonds – between + and – charged R groups

• §  Disulfide bridges – covalent bonds occurring in
• sulfhydryl groups (strongest)

o    Chaperone proteins help structural formation

• Hydrophobic 
• H-Bond - polar
• Ionic - charged
• Disulfide - sulfhydryl groups

• 2 or more polypeptides to produce shape of
• proteins

• Primary is amino acids building together
• Secondary is amino acids making long chains of itselves
• Tertiary is R groups attaching to R groups
• Quaternary is everyone

§  Heat

§  pH

§  ion charge

§  immersion in organic solvents

Spoiling bacteria

Blanching fruits denatures browning enzymes

Temporarily straightening hair

Gastrin denatured by pH of intestine

Meats easier to chew bc proteins denatured

Hydroxyl group on carbon 2

Each strand of DNA has a free phosphate group at one end and a free sugar on the other end = phosphate and sugar always line up

Read info

Second messenger of hormones

Products have more energy; energy is stored

Reactants have more energy; energy is released

• Change of state
• Diffusion
• More moles
• Complex -> simple

Exothermic

Free energy is energy that can do useful work. The entropy of the universe increases with any change, even apparently orderly changes have an even greater disorder caused by energy yielding catabolic processes. This disorder makes useful work.

Cells makes reactions into long series in which a product can be a reactant of another reaction, with the end product being waste.

ATPase hydrolyzes the ATP terminal phosphate to create ADP with an inorganic phosphate, releasing 31 kJ/mol (54 kJ/mol in a living cell), enough to make free energy to drive endergonic processes. However, to make sure this energy doesn't come off as heat, killing the cell, the iorganic phosphate attaches to another molecule through phosphorylation

• ·        
• Enzyme
• concentration: the more, the higher the rate of reaction

• ·        
• Substrate
• concentration: the more, the higher the rate of reaction

• ·        
• Temperature:
• only to a certain optimal point before it denatures and rate goes down

• ·        
• pH:
• only to a certain optimal point before it denatures and rate goes down

help enzymes function by binding to active sites with covalent bonds, or binding weakly with substrate

Competitve takes the actual active site; noncompetive takes an allosteric site to change conformation and affinity