Proteins

Question 1

PROTEINs

Answer 1

• large molecules that contain
  C / H / O / N ~ S
• are more complex than carbs/fats

Question 2

AMINO ACIDs

Answer 2

• are the monomers of proteins
• 20 kinds

Question 3

FUNCTIONs of PROTEINs

Answer 3

• structural - form structural framework of various parts of rthe body
  e.g. collagen - bone/connective tisse // keratin - skin/hair/nails
• regulatory - regulates physiological processes
  e.g. control growth + development, mediates CNS responses
  i.e. insulin - regulates BGL, substance P - neurotransmitter mediates sensation of pain
• contractile - allows shortening of muscle cells
  e.g. mysoin + actin produce movement
• immunological - antibodies + interleukins protect against foreign substances/pathogens
• transport - carries vital substances throughout body
  e.g. hemoglobin transports O2, lipoprotein transports lipids
• catalytic - act as enzymes that regulate biochemical reactions
  e.g. salivary amylase / sucrase / ATPase

Question 4

ENZYMEs

Answer 4

most catalysts are proteins

some are two parts
- apoenzyme - protein portion
- cofactor - non-protein ~metal ions ( Fe / Mg / Zn / Ca)
// organic cofactor = coenzyme - derived from vitamins

Question 5

ENZYME GROUPs

Answer 5

• OXIDASEs - add O2
• KINASEs - add PO4-3
• DEHYDROGENASE - remove H+
• ATPASE - splits ATP
• ANHYDRASE removes H2O
• PROTEASE breaks down proteins
• LIPASE breaks down triglycerides

Question 6

ENZYMEs are

HIGHLY SPECIFIC

Answer 6

• each enzyme binds only to specific substrates (reactant molecule), thus catalyze specific reactions
• active site - part that catalyzes reaction, fits into substrate like - lock + key
• induced fit - active site changes shape to fit

Question 7

ENZYMEs are

VERY EFFICIENT

Answer 7

• under optimal conditions = reaction rates are 100million - 10 billion X faster
• **substrate&raquo_space; product /s ** = 1-10k ~ upto +600k/s

Question 8

ENZYMEs are

SUBJECT to VARIETY of CELLULAR CONTROL

Answer 8

• rates of reactions - controlled by GENEs - ENHANCE // INHIBIT
• enzymes have active + inactive forms

Question 9

ENZYMATIC PROCESS

Answer 9

1. when enzyme + substrate make contact&raquo_space; temporary compound called enzyme-substrate complex
2. substrates transformed by rearrangement of existing atoms - breakdown//combine&raquo_space; products
3. after reaction is completed - unchanged enzymes is free to attach to next substrate