Biological molecules Exam Questions
with Latest Update
what do enzymes do - Answer-they act as biological catalysts- they increase the speed
of reactions without being changed or used up in those reactions
what do enzymes reduce the need for - Answer-high temperatures - we have enzymes
to speed up useful chemical reactions in the body (metabolic reactions)
what are enzyms made of - Answer-enzymes are made of proteins- which are made up
of chains of amino acids (these chains are folded into unique shapes)
what is a substrate - Answer-a molecule that is changed in a reaction
what does the substrate of the enzyme join on to? - Answer-the active site
how many reactions do enzymes noramally speed up and why - Answer-typically 1,
because the substrate has to be a specific shape to fit into the active site
what is the lock and key metod used to describe - Answer-the way that an enzyme
substrate fits into the active site
changing the temperature changes the [...] of an enzyme-[...] - Answer-changing the
temperature changes the rate of an enzyme-catalysed reaction
why does increasing the temperature increase the enzyme chances of reaction -
Answer-because the enzyme and substrate will have more energy, and so move about
more, and are more likely to collide and form enzyme -substrate-complexes
what happens to enzymes when the temperature gets too hot - Answer-they denature-
the bonds holding the enzymes together break
what does denaturing do to the enzyme - Answer-when the bonds break the shape of
the active site changes and the substrate no longer fits -enzyme is dentured
when does an enzyme work best - Answer-at its optimum teperature
what does a change in pH do to an enzyme - Answer-if its too high or too low the pH
denatures the enzyme (interfears with the bonds holding the enzyme together changing
shape of active site)
what is the optimum pH for a typical enzyme - Answer-neutral pH 7
, what does the enzyme amylase do - Answer-it catalyses the break down of starch into
maltose
how can you use amylase to measure enzyme activity - Answer-you can detect if starch
is present using iodine solution
what would you do first when investigating the effect of temperature on enzyme activity -
Answer--mix up and heat starch an amylase solution in a waterbath at desired temp. -
add a drop of iodine solution to each well on a spotting tile, -every 10 seconds add a
drop of solution (amylase & starch) using a pipette to the iodine on the spotting tile
when the solution on the spotting tile remains browny orange what does that mean? and
what should you do - Answer-starch is no longer present (has been broken down by
amylase), you should record the time taken for this to happen
what do you need to repeat to see how different temperatures affect the time taken for
starch to be broken down - Answer-the experiment with different water bath
temperatures
what do you need to control when carrrying out any experiment - Answer-the variables
The front of this card is blank. More information - Answer-The front of this card is blank.
More information
what are the chemical elements present in carbohydrates? - Answer-carbon, hydrogen
and oxygen
what are the chemical elements present in protein? - Answer-carbon, nitrogen,
hydrogen and oxygen
what are the chemical elements present in lipids? - Answer-carbon, hydrogen and
oxygen
what is the strucure of carbohydrates? - Answer-starch and glycogen are (large
moleculed complex carbs) made up of smaller units (simple sugars) like glucose or
maltose molecules that join together, forming a chain
what is the structure of proteins? - Answer-long chains of amino acids
what is the structure of lipids? - Answer-fatty acids and glycerol
what is a catalyst? - Answer-a substance which increases the speed of a reaction
without being used up or changed in the reaction
as pH gets closer to optimum what happens to the rate of reaction - Answer-it increases
until optimum, then it decreases when the enzyme nenatures
with Latest Update
what do enzymes do - Answer-they act as biological catalysts- they increase the speed
of reactions without being changed or used up in those reactions
what do enzymes reduce the need for - Answer-high temperatures - we have enzymes
to speed up useful chemical reactions in the body (metabolic reactions)
what are enzyms made of - Answer-enzymes are made of proteins- which are made up
of chains of amino acids (these chains are folded into unique shapes)
what is a substrate - Answer-a molecule that is changed in a reaction
what does the substrate of the enzyme join on to? - Answer-the active site
how many reactions do enzymes noramally speed up and why - Answer-typically 1,
because the substrate has to be a specific shape to fit into the active site
what is the lock and key metod used to describe - Answer-the way that an enzyme
substrate fits into the active site
changing the temperature changes the [...] of an enzyme-[...] - Answer-changing the
temperature changes the rate of an enzyme-catalysed reaction
why does increasing the temperature increase the enzyme chances of reaction -
Answer-because the enzyme and substrate will have more energy, and so move about
more, and are more likely to collide and form enzyme -substrate-complexes
what happens to enzymes when the temperature gets too hot - Answer-they denature-
the bonds holding the enzymes together break
what does denaturing do to the enzyme - Answer-when the bonds break the shape of
the active site changes and the substrate no longer fits -enzyme is dentured
when does an enzyme work best - Answer-at its optimum teperature
what does a change in pH do to an enzyme - Answer-if its too high or too low the pH
denatures the enzyme (interfears with the bonds holding the enzyme together changing
shape of active site)
what is the optimum pH for a typical enzyme - Answer-neutral pH 7
, what does the enzyme amylase do - Answer-it catalyses the break down of starch into
maltose
how can you use amylase to measure enzyme activity - Answer-you can detect if starch
is present using iodine solution
what would you do first when investigating the effect of temperature on enzyme activity -
Answer--mix up and heat starch an amylase solution in a waterbath at desired temp. -
add a drop of iodine solution to each well on a spotting tile, -every 10 seconds add a
drop of solution (amylase & starch) using a pipette to the iodine on the spotting tile
when the solution on the spotting tile remains browny orange what does that mean? and
what should you do - Answer-starch is no longer present (has been broken down by
amylase), you should record the time taken for this to happen
what do you need to repeat to see how different temperatures affect the time taken for
starch to be broken down - Answer-the experiment with different water bath
temperatures
what do you need to control when carrrying out any experiment - Answer-the variables
The front of this card is blank. More information - Answer-The front of this card is blank.
More information
what are the chemical elements present in carbohydrates? - Answer-carbon, hydrogen
and oxygen
what are the chemical elements present in protein? - Answer-carbon, nitrogen,
hydrogen and oxygen
what are the chemical elements present in lipids? - Answer-carbon, hydrogen and
oxygen
what is the strucure of carbohydrates? - Answer-starch and glycogen are (large
moleculed complex carbs) made up of smaller units (simple sugars) like glucose or
maltose molecules that join together, forming a chain
what is the structure of proteins? - Answer-long chains of amino acids
what is the structure of lipids? - Answer-fatty acids and glycerol
what is a catalyst? - Answer-a substance which increases the speed of a reaction
without being used up or changed in the reaction
as pH gets closer to optimum what happens to the rate of reaction - Answer-it increases
until optimum, then it decreases when the enzyme nenatures
