INTRODUCTION TO BIOCHEMISTRY FINAL
EXAM WITH 150+ QUESTIONS AND WEL
DETAILED ANSWERS|| GUARANTEED PASS ||
ALREADY GRADED A+|| 2025/2026 LATEST
UPDATE!!!
What are some of the general mechanisms by which a drug can work? -
ANSWER-With receptors - nuclear, ion channels, metabotropic, enzyme linked.
Enzymes.
Non receptor change the physical chemical properties such as antacids and
osmotic fluid expanders.
How is drug action monitored in labs? - ANSWER-Using Bioassays.
Tissue/cels grown and drug is added to monitor the effect on it.
What is a dose-response relationship curve? - ANSWER-Also known as a
concentration response curve. They are plotted on a log scale.
Y axis = an measurable, observable effect of the drug
X axis = concentration of drug
What is the law of mass action? - ANSWER-The higher amount of drug, the
faster the rate of reaction. There are more drug-receptor complexes which form.
These bindings need to be reversible and they both remain unchanged at the end
of the reaction.
What does the magnitude of a drug response depend on? - ANSWER-The
concentration of drug
,The number of receptors which are occupied by the drug
Rate of drug-receptor binding
What is the role of receptors in the body? - ANSWER-There are natural ligands
within the body which bind to these receptors. This causes a cellular response.
Drugs have similar structures and functions to these ligands to cause a cellular
response.
What are and how do agonists work? - ANSWER-Agonist = drugs which causes
a cellular response.
They bind to the receptor causing a conformational change which allows signal
transduction and response.
What is Ka and Kd? - ANSWER-Drug + Receptor <—> D-R complex
Ka = —> association constant
Kd = <— dissociation constant
What are the speeds of each type of receptor? - ANSWER-Ionotropic =
milliseconds
Metabotropic = seconds
Enzyme-linked = hours
Nuclear = hours
What is the definition of pharmacodynamics? - ANSWER-The drugs effect on
the body
What is the definition of pharmacokinetics? - ANSWER-How the body deals
with the drug. ADME
,What is the general movement of a drug within the body? - ANSWER-It is
administered. Goes through the gastrointestinal tract. It is absorbed into the
blood. Some become bound to proteins and other molecules in the blood. When
taken to the liver, some would be metabolised. Some is taken to the target organ
to have effect.
Metabolites and free drug can be excreted through the kidneys.
What are some of the different administration methods of drugs? -
ANSWERSuppositories = rectal membrane
Oral = buccaneer cavity/gastric mucosa
Inhaled = pulmonary epithelium (fastest route)
Transdermal patches = skin
What are properties of a molecule which enable easy absorption? -
ANSWERSmall, non-polar. This allows them to diffuse straight across the
phospholipid bilayer. Passive diffusion.
How are large or water-soluble drugs absorbed? - ANSWER-Through aqueous
channels.
Carrier proteins. There may be a limited number, so saturation causes
competition.
Pinocytosis (endocytosis of dissolved drugs from ECF).
Why does some drug not get absorbed? - ANSWER-Some may be digested by
bacteria in the small intestine. Pre-systemic metabolism.
In which environments are basic or acidic drugs better absorbed? -
ANSWERAcidic in acidic environment. This is because it remains unionised.
This allows easier diffusion.
Basic in basic environment.
, What are some of the pH in different part of the digestive tract in which drugs
can be absorbed from? - ANSWER-Oesophagus: pH 5-6. Fast movement
through this, tissue is thick. There is little to no absorption.
Stomach: pH 2-6, 1.5-2 after food is eaten. Basic drugs would dissolve here but
acidic drugs would be better absorbed. Acidic drugs need to be taken with food,
to prevent damage to stomach
Small intestine: pH 6-6.5 in the jejunum and duodenum, 7-8 in the ileum. Can
cause hydrolysis of prodrug esters to form the active drug which will be
absorbed.
Colon: pH5-5.7. There is limited absorption here.
What is an example of a negative modulator? - ANSWER-There may be a chain
of reactions. One of the products (usually the end product) is a modulator. It
binds to the allosteric site.
When there is low levels of this product, there is low levels of this product, it is
released form the site and allows enzyme activity.
What is positive modulation? - ANSWER-When the modulator binds to the
allosteric site, it causes a conformational change which allows the enzyme to
work. Promotes enzyme activity.
What is the concentration rate graph for an allosteric enzyme? - ANSWER-A
sigmoidal curve. They reach Vmax but use a different reaction pathway. In the
steep, linear part of the graph, this shows that a small concentration of substrate
can increase rate greatly.
This allows control when a molecule's concentration fluctuates over a narrow
range. There would be a quick response to regulate levels.
What is homotrophic and heterotrophic regulation? - ANSWER-Homotrophic =
the substrate is also the regulatory molecule (oxygen and Hb)
Heterotrophic = modulator is not the substrate (2,3-bisphosphoglycate, CO2 and
H+ can all regulate Hb)
EXAM WITH 150+ QUESTIONS AND WEL
DETAILED ANSWERS|| GUARANTEED PASS ||
ALREADY GRADED A+|| 2025/2026 LATEST
UPDATE!!!
What are some of the general mechanisms by which a drug can work? -
ANSWER-With receptors - nuclear, ion channels, metabotropic, enzyme linked.
Enzymes.
Non receptor change the physical chemical properties such as antacids and
osmotic fluid expanders.
How is drug action monitored in labs? - ANSWER-Using Bioassays.
Tissue/cels grown and drug is added to monitor the effect on it.
What is a dose-response relationship curve? - ANSWER-Also known as a
concentration response curve. They are plotted on a log scale.
Y axis = an measurable, observable effect of the drug
X axis = concentration of drug
What is the law of mass action? - ANSWER-The higher amount of drug, the
faster the rate of reaction. There are more drug-receptor complexes which form.
These bindings need to be reversible and they both remain unchanged at the end
of the reaction.
What does the magnitude of a drug response depend on? - ANSWER-The
concentration of drug
,The number of receptors which are occupied by the drug
Rate of drug-receptor binding
What is the role of receptors in the body? - ANSWER-There are natural ligands
within the body which bind to these receptors. This causes a cellular response.
Drugs have similar structures and functions to these ligands to cause a cellular
response.
What are and how do agonists work? - ANSWER-Agonist = drugs which causes
a cellular response.
They bind to the receptor causing a conformational change which allows signal
transduction and response.
What is Ka and Kd? - ANSWER-Drug + Receptor <—> D-R complex
Ka = —> association constant
Kd = <— dissociation constant
What are the speeds of each type of receptor? - ANSWER-Ionotropic =
milliseconds
Metabotropic = seconds
Enzyme-linked = hours
Nuclear = hours
What is the definition of pharmacodynamics? - ANSWER-The drugs effect on
the body
What is the definition of pharmacokinetics? - ANSWER-How the body deals
with the drug. ADME
,What is the general movement of a drug within the body? - ANSWER-It is
administered. Goes through the gastrointestinal tract. It is absorbed into the
blood. Some become bound to proteins and other molecules in the blood. When
taken to the liver, some would be metabolised. Some is taken to the target organ
to have effect.
Metabolites and free drug can be excreted through the kidneys.
What are some of the different administration methods of drugs? -
ANSWERSuppositories = rectal membrane
Oral = buccaneer cavity/gastric mucosa
Inhaled = pulmonary epithelium (fastest route)
Transdermal patches = skin
What are properties of a molecule which enable easy absorption? -
ANSWERSmall, non-polar. This allows them to diffuse straight across the
phospholipid bilayer. Passive diffusion.
How are large or water-soluble drugs absorbed? - ANSWER-Through aqueous
channels.
Carrier proteins. There may be a limited number, so saturation causes
competition.
Pinocytosis (endocytosis of dissolved drugs from ECF).
Why does some drug not get absorbed? - ANSWER-Some may be digested by
bacteria in the small intestine. Pre-systemic metabolism.
In which environments are basic or acidic drugs better absorbed? -
ANSWERAcidic in acidic environment. This is because it remains unionised.
This allows easier diffusion.
Basic in basic environment.
, What are some of the pH in different part of the digestive tract in which drugs
can be absorbed from? - ANSWER-Oesophagus: pH 5-6. Fast movement
through this, tissue is thick. There is little to no absorption.
Stomach: pH 2-6, 1.5-2 after food is eaten. Basic drugs would dissolve here but
acidic drugs would be better absorbed. Acidic drugs need to be taken with food,
to prevent damage to stomach
Small intestine: pH 6-6.5 in the jejunum and duodenum, 7-8 in the ileum. Can
cause hydrolysis of prodrug esters to form the active drug which will be
absorbed.
Colon: pH5-5.7. There is limited absorption here.
What is an example of a negative modulator? - ANSWER-There may be a chain
of reactions. One of the products (usually the end product) is a modulator. It
binds to the allosteric site.
When there is low levels of this product, there is low levels of this product, it is
released form the site and allows enzyme activity.
What is positive modulation? - ANSWER-When the modulator binds to the
allosteric site, it causes a conformational change which allows the enzyme to
work. Promotes enzyme activity.
What is the concentration rate graph for an allosteric enzyme? - ANSWER-A
sigmoidal curve. They reach Vmax but use a different reaction pathway. In the
steep, linear part of the graph, this shows that a small concentration of substrate
can increase rate greatly.
This allows control when a molecule's concentration fluctuates over a narrow
range. There would be a quick response to regulate levels.
What is homotrophic and heterotrophic regulation? - ANSWER-Homotrophic =
the substrate is also the regulatory molecule (oxygen and Hb)
Heterotrophic = modulator is not the substrate (2,3-bisphosphoglycate, CO2 and
H+ can all regulate Hb)
