biological molecules and enzymes Flashcards
Define biological moelcule
organic molecules found in living things
What are the chemicals that make up carbohydrates (3)
carbon
hydrogen
oxygen
Define carbohydrates
molecules made up of small basic units called simple sugars
Define starch
energy storage molecule in plants
Define glycogen
energy storage in animals
Define protein
complex biological macromolecule made up of amino acid monomers, that can have a wide variety of forms and functions
What chemical elements do amino acids/proten consist of (4)
carbon
hydrogen
oxygen
nitrogen
Define lipids
Macromolecules consisting of glycerol and fatty acids
what chemical elements do lipids consist of (3)
carbon
hydrogen
oxygen
Which simple sugar is used to form starch and glycogen
glucose monosaccharides
Which chemical to use to test for reducing sugars
Benedict’s solution
Colour change for positive reaction for reducing sugars
blue to orange-red
Which chemical to use to test for starch
iodine solution
Colour change for positive reaction for starch
brown to dark blue black
Which chemical to use to test for proteins
Biuret reagent
Colour change for positive reaction for proteins
blue to purple
Which chemicals to use to test for lipids
ethanol and distilled water
Colour change for positive reaction for lipids
clear to milky white cloudy EMULSION
Water has properties that makes it a good solvent.
True or False
true
Define enzymes
proteins tht function as biological catalyst
Explain enzyme action (5)
Each type of enzyme has a unique active site to which a specific substrate can bind
The shape of active site is COMPLEMENTARY to its substrate
substrate fits into enzyme
enzyme substrate complex formed
products may have formed (Bond of substrate broken under stress) or substrates combined into one product
Define a catalyst (generallly)
a substance that increases the rate of reaction without being changed or used up in the process
Define a substrate
molecule enzyme binds to at start of reaction
Enzymes are specific and unique
True or false
true
Explain the effect of temperature on enzyme activity (5)
As temperature increases, molecules gain more kinetic energy and move faster
Increase in the frequency of effective collisions between substrate and enzyme active sites
The rate of enzyme catalysed reactions increases up to the optimum temperature
beyond optimum temperature, enzyme molecule vibrate so mcuh that they start to change the shape of the active site (denaturation)
Rate of reaction decreases as the active site is no longer complementary to the substrate
Effect of pH on enzyme acitvity (3)
Enzymes have an optimum pH at which the rate of enzyme catalysed reaction is highest
A change of pH on either side of the optimum pH results in a change in shape of the enzyme’s active site
Causes denauration (active site no longer complementary)
