B3.biological molecules Flashcards
list the chemical elements that make up lipids, carbohydrates and proteins
they all have carbon , oxygen and hydrogen but proteins also consist of nitrogen and sulphur
what are carbohydrates made of
glucose, starch
what are proteins made of
amino acid
what are lipids made of
fatty acids, glycerol
state what the iodine test is for and it’s potential results if positive or negative
for starch
if + blue/ black
if - orange/brown
state what the biuret test is for and it’s potential results if positive or negative
protein
if+ mauve
if - light blue
state what the Benedict test is for, the conditions to make it work and it’s potential results if positive or negative
for reducing sugar
needs to be heated
if + green-orange-red
if- deep blue
state what the ethanol test is for, the conditions to make it work and it’s potential results if positive or negative
for lipids
you need to dissolve the food in ethanol then pour it in the water
if + cloudy
if - clear
define what are enzymes
proteins that act like biological catalysts
state the effect of temperature on enzyme activity
increased sped up movements of enzymes and substrates
increased product formation
there’s an optimum temperature for each of them
if the temperature increases significantly if causes the enzyme to change shape because it vibrates so much that the substrate can no longer fit so the enzyme becomes denatured/ dead
define the effect of PH on enzyme activity
can cause enzymes to denature
can lower the activity therefore the rate of product formation