SPA+notes

1) write specific procedure with details (as though the teachers don't know anything) 2) clear 3) systematic 4) concise

say: -label white tile -add a drop of iodine each onto A,B and C -equal amounts of substrate and enzyme -use thermometer to measure 37 degrees (use word incubate)

-to show difference in colour -as a control -comparison between beginning and end
 * must test for starch at the beginning before putting into water bath

-it's the mixture that turned colour, not the iodine itself
 * use the words"remained"/ "turned" for iodine test

-use the word "hydrolysed" for starch
 * starch "present" or "absent"

Possible precautions: -ensure tile is dry -no parallax error -ensure that you mention precautions in the procedure -explain precautions
 * Tube || Contents |||| Observations || Conclusions ||
 * ||  || 0min || 10min ||   ||
 * X || B + A || turned blue- black || remained brown || Starch is absent. Starch is hydrolysed ||
 * Y || C + A || turned blue-black || turned blue-black || Starch is present ||

-add equal amount of benedict's solution to unknown -mix -submerge in boiling water bath for 5 min/ when see coloured precipitate (from green to yellow to orange to brick-red) formed -if remains blue, reducing sugar is absent
 * REDUCING SUGARS TEST**

-test tube must be dry -one or two drops of oil -or ground solid -add ethanol -water -shake -should see white suspension -exothermic reaction (should become warm)
 * ETHANOL EMULSION TEST**

- salivary enzymes(amylase) work best in pH 7 - pepsin(stomach enzymes) work best in pH 4 - intestinal enzymes work best in alkaline pH
 * need to know diffusion, osmosis, digestion, food tests, carbo lipid protein

-acids make protein coagulate
 * proteins coagulate/change structure is different from digestion