BMAT Section 2 2021 Answers Explained
Thank you for using this document to aid your revision for the BMAT. Whether you use it in full or in
part, you should hopefully benefit from reading it. This document contains in-depth explanations for
the answers to the BMAT 2021 Section 2 paper.
DISCLAIMER
Whilst every effort has been made by the author to keep the content in this document factually
correct, errors can still occur. The author assumes no responsibility or liability for any errors or
omissions which may be present in this document. Additionally, the author provides no guarantee of
completeness and accuracy, and the user assumes full responsibility for its use.
1. G
● Cardiovascular diseases are diseases of the heart and blood vessels. In the arteries,
atherosclerotic plaques can form and this narrows the lumen of such arteries, thus
reducing blood flow to the organs it supplies. This can lead to symptoms of pain
upon exertion which is due to insufficient blood flow, or in extreme cases, death of
the organ due to cessation of blood flow (due to rupture of the plaque, forming blot
clots too quickly hence blocks off the artery).
● Stem cells are cells which don’t belong to any specific, functionally active cell type.
They can differentiate and specialise into a particular functionally active cell. The
crucial aspect is that they’re capable of self renewal, which means they can replenish
the “pool” of stem cells as they differentiate. These can be broadly divided:
- Totipotent: stem cells which retain the ability to differentiate into any type of
cell i.e. embryonic stem cells
- Pluripotent: slight differentiated stem cells, hence can differentiate into most
types of cells but not all.
- Multipotent: Even more differentiated stem cells, and can only differentiate
into closely related family of cells.
- Oligopotent: Even more differentiated stem cells (more than multipotent)
which can differentiate into cells within the cell lineage.
- Unipotent: the most differentiated stem cells which can only differentiate to
a particular cell.
● Taking each statement in turn:
- Statement 1 is incorrect as cardiovascular disease isn’t a communicable
disease. Communicable diseases are diseases which can spread from an
infected host to another unaffected individual e.g. infectious diseases.
- Statement 2 is correct as embryonic stem cells are totipotent hence can
differentiate into cardiac muscle cells.
All rights reserved . Author: Shyam Parmar. Created in 2022.
, - Statement 3 is correct because cancer is uncontrolled cell division, and stem
cells survive much longer than adult cells hence there is an increased risk
that they accumulate sufficient mutations over time, resulting in
unregulated self renewal and developing cancer.
2. D
● Z3- ion has 3 “excess” electrons thus giving it a charge of 3-. Since the electronic
configuration of Z3- is 2,8,8, then atom Z must have the configuration 2,8,5.
● Imagine taking electrons out of an ion; it must be taken out from the outer shells
first before moving onto the next innermost shell, as electrons have higher energies
the higher the energy shell number they’re occupied in.
● Z must be a p block element as the 3rd shell has 5 electrons, and this can be
rewritten as:
(where the squared bracket tells us the electron configuration of the noble gas element
before addition of further electrons in the next highest shell).
● This is important as calculating group numbers depends on whether the element is a
s,p or d block element.
- S block: group number is either 1 or 2 (depending on number of outer shell
electrons)
- P block: group number is the number of outer shell electrons, plus 10.
- D block: group number is the number of electrons in the highest level s and
highest level d orbital
● Since Z is a p block element with configuration of 2,8,5, this means the group
number is 15.
3. G
● Imagine the following scenario:
All rights reserved . Author: Shyam Parmar. Created in 2022.
, ● The weight of the ball is 50N whilst the magnitude of air resistance is 50N (stated in
question). However, because the direction of air resistance is opposite to the
direction of the weight, then we denote the air resistance with a negative sign (i.e.
-50N).
● Since these 2 forces oppose each other then the net (resultant) force is 0N (they
cancel each other out). So statement 2 is correct.
● A net (non-zero) resultant force causes the object to accelerate (i.e. increase it’s
speed in a given direction) in the direction of the net force. So if there is no resultant
force, then the object doesn’t accelerate, therefore the object is travelling at its
terminal velocity (i.e. fastest possible speed in a given direction). So statement 3 is
correct.
● Statement 1 is incorrect because the object has no net resultant force acting on it
(see the previous paragraph).
4. E
● There are many ways to simplify this expression. One way is to treat the expression
as the multiplication of 2 numbers:
● You can focus on simplifying the 2nd number by a bracket law of indices. i.e. If a term
with a power is itself raised to a power then the powers are multiplied together.
● This then gives:
● Now simplify like terms together. The x in the 3xy term increases the power of the x
in the numerator (x6) leaving x7. The y in the denominator (y8) “cancels out” the y in
3xy term thus leaving y7.
All rights reserved . Author: Shyam Parmar. Created in 2022.
, 5. A
● The fundamental principle here is that the enzymes catalyse a reaction(s) that
ultimately cause the apple pieces to turn brown.
● Statement 1 is wrong because at pH 9 (weakly alkaline) the time taken for browning
(pH9 – 6s) is much less than if the enzyme was placed in more acidic conditions (pH3
– 22s; pH5 – 10s) meaning the enzyme ‘works’ faster at a weakly alkaline condition
than in acidic condition (all else being equal).
● Statement 2 is wrong as the table shows that (assuming no aqueous sodium chloride
present) the enzyme at pH7 works just as fast as the enzyme at pH9 (both take 6s).
There is no data in the table showing how well the enzyme works (i.e. time taken) in
between these 2 pH values. For example, it could be the case that at pH8 (or any
other pH between 7 and 9) the time taken for browning is <6s. Hence we can’t
conclude what the optimum pH is from the data availble.
● Statement 3 is wrong because the enzyme at pH7 with aqueous sodium chloride
[NaCl(aq)], takes a longer time to cause browning than the enzyme at pH7 without
NaCl(aq), suggesting that the presence of NaCl(aq) inhibits the enzyme’s activity (it’s
important to make sure that the comparison needs to involve identical pH so that it
is a fair comparison).
6. B
● Le Chatelier’s law essentially states that If you change the conditions in an
equilibrium reaction, then the position of equilibrium will change to counteract the
change you induced.
● i.e. if you increased the temperature, equilibrium will favour the reaction to decrease
the temperature
● i.e. if you increase the pressure, equilibrium will shift to favour the reaction which
produces the fewest moles of product
● Statement 1 is correct; there are more moles of reactants (water and ethene) than
there are of ethanol. So increasing pressure in this case, will favour the forward
reaction (i.e. the reaction which produces the fewest moles) to reduce pressure.
Fewer moles means there is less pressure as there are fewer collisions.
● Statement 2 is wrong; the forward reaction is exothermic (releases heat) given the
negative enthalpy change, and the backward reaction is endothermic (absorbs heat).
So increasing the temperature would favour the backward reaction (heat absorbing),
to reduce temperature.
All rights reserved . Author: Shyam Parmar. Created in 2022.
Thank you for using this document to aid your revision for the BMAT. Whether you use it in full or in
part, you should hopefully benefit from reading it. This document contains in-depth explanations for
the answers to the BMAT 2021 Section 2 paper.
DISCLAIMER
Whilst every effort has been made by the author to keep the content in this document factually
correct, errors can still occur. The author assumes no responsibility or liability for any errors or
omissions which may be present in this document. Additionally, the author provides no guarantee of
completeness and accuracy, and the user assumes full responsibility for its use.
1. G
● Cardiovascular diseases are diseases of the heart and blood vessels. In the arteries,
atherosclerotic plaques can form and this narrows the lumen of such arteries, thus
reducing blood flow to the organs it supplies. This can lead to symptoms of pain
upon exertion which is due to insufficient blood flow, or in extreme cases, death of
the organ due to cessation of blood flow (due to rupture of the plaque, forming blot
clots too quickly hence blocks off the artery).
● Stem cells are cells which don’t belong to any specific, functionally active cell type.
They can differentiate and specialise into a particular functionally active cell. The
crucial aspect is that they’re capable of self renewal, which means they can replenish
the “pool” of stem cells as they differentiate. These can be broadly divided:
- Totipotent: stem cells which retain the ability to differentiate into any type of
cell i.e. embryonic stem cells
- Pluripotent: slight differentiated stem cells, hence can differentiate into most
types of cells but not all.
- Multipotent: Even more differentiated stem cells, and can only differentiate
into closely related family of cells.
- Oligopotent: Even more differentiated stem cells (more than multipotent)
which can differentiate into cells within the cell lineage.
- Unipotent: the most differentiated stem cells which can only differentiate to
a particular cell.
● Taking each statement in turn:
- Statement 1 is incorrect as cardiovascular disease isn’t a communicable
disease. Communicable diseases are diseases which can spread from an
infected host to another unaffected individual e.g. infectious diseases.
- Statement 2 is correct as embryonic stem cells are totipotent hence can
differentiate into cardiac muscle cells.
All rights reserved . Author: Shyam Parmar. Created in 2022.
, - Statement 3 is correct because cancer is uncontrolled cell division, and stem
cells survive much longer than adult cells hence there is an increased risk
that they accumulate sufficient mutations over time, resulting in
unregulated self renewal and developing cancer.
2. D
● Z3- ion has 3 “excess” electrons thus giving it a charge of 3-. Since the electronic
configuration of Z3- is 2,8,8, then atom Z must have the configuration 2,8,5.
● Imagine taking electrons out of an ion; it must be taken out from the outer shells
first before moving onto the next innermost shell, as electrons have higher energies
the higher the energy shell number they’re occupied in.
● Z must be a p block element as the 3rd shell has 5 electrons, and this can be
rewritten as:
(where the squared bracket tells us the electron configuration of the noble gas element
before addition of further electrons in the next highest shell).
● This is important as calculating group numbers depends on whether the element is a
s,p or d block element.
- S block: group number is either 1 or 2 (depending on number of outer shell
electrons)
- P block: group number is the number of outer shell electrons, plus 10.
- D block: group number is the number of electrons in the highest level s and
highest level d orbital
● Since Z is a p block element with configuration of 2,8,5, this means the group
number is 15.
3. G
● Imagine the following scenario:
All rights reserved . Author: Shyam Parmar. Created in 2022.
, ● The weight of the ball is 50N whilst the magnitude of air resistance is 50N (stated in
question). However, because the direction of air resistance is opposite to the
direction of the weight, then we denote the air resistance with a negative sign (i.e.
-50N).
● Since these 2 forces oppose each other then the net (resultant) force is 0N (they
cancel each other out). So statement 2 is correct.
● A net (non-zero) resultant force causes the object to accelerate (i.e. increase it’s
speed in a given direction) in the direction of the net force. So if there is no resultant
force, then the object doesn’t accelerate, therefore the object is travelling at its
terminal velocity (i.e. fastest possible speed in a given direction). So statement 3 is
correct.
● Statement 1 is incorrect because the object has no net resultant force acting on it
(see the previous paragraph).
4. E
● There are many ways to simplify this expression. One way is to treat the expression
as the multiplication of 2 numbers:
● You can focus on simplifying the 2nd number by a bracket law of indices. i.e. If a term
with a power is itself raised to a power then the powers are multiplied together.
● This then gives:
● Now simplify like terms together. The x in the 3xy term increases the power of the x
in the numerator (x6) leaving x7. The y in the denominator (y8) “cancels out” the y in
3xy term thus leaving y7.
All rights reserved . Author: Shyam Parmar. Created in 2022.
, 5. A
● The fundamental principle here is that the enzymes catalyse a reaction(s) that
ultimately cause the apple pieces to turn brown.
● Statement 1 is wrong because at pH 9 (weakly alkaline) the time taken for browning
(pH9 – 6s) is much less than if the enzyme was placed in more acidic conditions (pH3
– 22s; pH5 – 10s) meaning the enzyme ‘works’ faster at a weakly alkaline condition
than in acidic condition (all else being equal).
● Statement 2 is wrong as the table shows that (assuming no aqueous sodium chloride
present) the enzyme at pH7 works just as fast as the enzyme at pH9 (both take 6s).
There is no data in the table showing how well the enzyme works (i.e. time taken) in
between these 2 pH values. For example, it could be the case that at pH8 (or any
other pH between 7 and 9) the time taken for browning is <6s. Hence we can’t
conclude what the optimum pH is from the data availble.
● Statement 3 is wrong because the enzyme at pH7 with aqueous sodium chloride
[NaCl(aq)], takes a longer time to cause browning than the enzyme at pH7 without
NaCl(aq), suggesting that the presence of NaCl(aq) inhibits the enzyme’s activity (it’s
important to make sure that the comparison needs to involve identical pH so that it
is a fair comparison).
6. B
● Le Chatelier’s law essentially states that If you change the conditions in an
equilibrium reaction, then the position of equilibrium will change to counteract the
change you induced.
● i.e. if you increased the temperature, equilibrium will favour the reaction to decrease
the temperature
● i.e. if you increase the pressure, equilibrium will shift to favour the reaction which
produces the fewest moles of product
● Statement 1 is correct; there are more moles of reactants (water and ethene) than
there are of ethanol. So increasing pressure in this case, will favour the forward
reaction (i.e. the reaction which produces the fewest moles) to reduce pressure.
Fewer moles means there is less pressure as there are fewer collisions.
● Statement 2 is wrong; the forward reaction is exothermic (releases heat) given the
negative enthalpy change, and the backward reaction is endothermic (absorbs heat).
So increasing the temperature would favour the backward reaction (heat absorbing),
to reduce temperature.
All rights reserved . Author: Shyam Parmar. Created in 2022.
