Entry test MDCAT contains most of the Biology MCQs. FSC Part 1 bio book MCQs. HSSC Biology questions MCQs. Solved Chapterwise Biology MCQs for first-year 11 class MCQs. Second-year and first-year bio textbooks chapter-wise MCQs with the answer are provided here. PakLearningSpot PLS MCQs Bank website for FREE Entry test preparations
PLS Boost Bundle
Get Access to 20 thousands+ MCQs Including Topical MCQs, Practice Tests, Mock Tests, Solved Past Papers, Flashcards, Notes, FLPS, and Much More.
An activated enzyme consisting of polypeptide chain and a cofactor is called:
Due to the similarity of structure, competitive inhibitors may be selected by the _______ site.
NUMS 2019 Reconduct
Biology
Enzymes
Elimination Tool:
A reaction will proceed faster if the activation energy is?
PMC Sample 1
Biology
Enzymes
Elimination Tool:
Biological molecules (proteins) which catalyze a biochemical reaction and remain unchanged after completion of reaction are called
If another molecule, having a shape very similar to the enzymes substrate, binds to its active site, it would then ____ the enzyme’s function:
NUMS 2020
Biology
Enzymes
Elimination Tool:
The effect of competitive inhibitor on enzyme activity is such that it affects which of the following?
PMC Sample 2
Biology
Enzymes
Elimination Tool:
The Induced fit model was introduced by Koshland in which of the following year?
PMC Sample 1
Biology
Enzymes
Elimination Tool:
The lock and key model of enzyme action was proposed by:
PMC Sample 3
Biology
Enzymes
Elimination Tool:
The cofactor usually acts as “bridge” between:
NUMS 2018
Biology
Enzymes
Elimination Tool:
Most enzymes have an optimum temperature of around:
PMC 2020
Biology
Enzymes
Elimination Tool:
Enzymes work by lowering the ______ of the reactions they catalyse:
PMC 2020
Biology
Enzymes
Elimination Tool:
If the non-protien part is loosely attached to the protein part in the enzyme, it is known as ______.
PMC Practice 3
Biology
Enzymes
Elimination Tool:
Which of the following statements is incorrect?
PMC Practice 1
Biology
Enzymes
Elimination Tool:
Enzymes _________ the activation energy of a chemical reaction
The pH at which the activity of pancreatic lipase enzyme is maximum is:
NUMS 2019 Cancelled
Biology
Enzymes
Elimination Tool:
The enzyme found in saliva responsible for the digestion of carbohydrates is:
NTS 2018
Biology
Enzymes
Elimination Tool:
Non-protein but inorganic, detachable co-factors are called ______:
NUMS 2020
Biology
Enzymes
Elimination Tool:
Which statement is incorrect about Lock and Key Model?
Reversible inhibitors form WEAK linkages with which of the following?
PMC Sample 3
Biology
Enzymes
Elimination Tool:
Which statement about enzyme is incorrect:
A three dimensional dcavity bearing a specific charge by which the enzyme reacts with its substrate is called
The structure of an enzyme is altered by:
The active site of an enzyme:
When inhibitor binds to enzyme other than active site and alters its structure, then it is called:
NUMS 2020
Biology
Enzymes
Elimination Tool:
Which of the following factors affect enzyme activity?
NTS 2011
Biology
Enzymes
Elimination Tool:
An example of competitive inhibition of an enzyme is the inhibition of;
UHS 2019
Biology
Enzymes
Elimination Tool:
If we add more substrate to an already occurring enzymatic reaction and it has no affect on the rate of reaction, the process is called?
PMC Practice 2
Biology
Enzymes
Elimination Tool:
A cofactor made of inorganic ion which is detachable is called
A/An _______ is mostly a non-protein chemical compound that is required for the protein’s biological activity.
NTS 2019
Biology
Enzymes
Elimination Tool:
Which type of bonds are never formed when a substrate fits into the active site of an enzyme?
PMC Practice 1
Biology
Enzymes
Elimination Tool:
Malonic acid is an example of:
Upon increasing the temperature the shape of enzyme’s active site?
PMC Sample 2
Biology
Enzymes
Elimination Tool:
The optimum pH for the enzyme arginase is which of the following?
PMC Sample 2
Biology
Enzymes
Elimination Tool:
The type of energy, reduced by the enzymes, for biological reactions to occur is called the:
UHS 2019
Biology
Enzymes
Elimination Tool:
Inhibitors which block the enzyme by forming weak bond are called
During feedback inhibition, which of the following structural part of enzyme is involved?
NUMS 2020
Biology
Enzymes
Elimination Tool:
Lock and Key Model for enzyme action propose by Emil Fischer suggests that:
PMC 2020
Biology
Enzymes
Elimination Tool:
A chemical substance which can react (in place of substrate) with the enzyme but is not transformed into product/s and thus blocks the active site temporarily or permanently is called
An enzyme increases the speed of a reaction:
NTS 2012
Biology
Enzymes
Elimination Tool:
Which of the following statements is incorrect?
PMC Sample 1
Biology
Enzymes
Elimination Tool:
The substrate binds to specific region of enzyme called?
PMC Sample 1
Biology
Enzymes
Elimination Tool:
The number of substrate molecules converted into the product by one molecule of enzyme active site per unit time is called?
PMC Practice 2
Biology
Enzymes
Elimination Tool:
Restriction endonucleases
PMC Sample 2
Biology
Enzymes
Elimination Tool:
Enzymes work by which of the following?
PMC Practice 1
Biology
Enzymes
Elimination Tool:
Inactive enzyme precursors such as pepsinogen for pepsin are called as:
PMC Practice 1
Biology
Enzymes
Elimination Tool:
Cyanide for enzymes act as:
NUMS 2018
Biology
Enzymes
Elimination Tool:
What is not true about the induced fit model:
NUMS 2018
Biology
Enzymes
Elimination Tool:
B
The inhibitor which closely resembles the substrate in its molecular structure and inhibits the enzyme activity by binding to the active site of the enzyme is called:
NTS 2013
Biology
Enzymes
Elimination Tool:
If the concentration of enzyme is kept constant and amount of substrate is increased a point is reached where increase in substrates concentration does not affect the reaction rate because of
| Lock and Key model was proposed by |
Which one forms the raw material for coenzymes?
Enzymes binds with chemical reactant which is known as?
PMC Sample 3
Biology
Enzymes
Elimination Tool:
If enzyme concentration is low than substrate pH and temperature values are equal to requirement then which of the following will increase rate of reaction.
Optimal temperature of enzymes present in human body is
Antibodies can be digested by using which of the following types of enzymes?
PMC Sample 3
Biology
Enzymes
Elimination Tool:
A student of chemical engineering mistakenly engulfed the toxic compound “A” which was a potent inhibitor of a certain enzyme. He was immediately brought to a hospital where the doctor injected, intravenously, substrate “B” to minimize the toxic effect of Compound A. His life was saved from serious damage. The treatment method shows that compound A was a ______ inhibitor.
UHS 2019
Biology
Enzymes
Elimination Tool:
If more substrate to already occurring enzymatic reaction is added and there is no effect on the rate of the reaction what is the form given to this situation:
In which of the following location enzymes controlling cellular respiration are present?
An activated enzyme made of polypeptide chain and a cofactor is?
PMC Practice 2
Biology
Enzymes
Elimination Tool:
Which step causes activation of catalytic site of an enzyme?
The enzyme in breast milk that causes the coagulation of milk or forms precipitates of milk is:
NUMS 2016
Biology
Enzymes
Elimination Tool:
Which of the following statements about enzymes is false?
PMC Sample 1
Biology
Enzymes
Elimination Tool:
The optimum pH of catalase is:
NUMS 2018
Biology
Enzymes
Elimination Tool:
A substance which binds at the active site of the enzyme but does not result in the formation of the products is called:
In enzymatic mechanism, the substrate bind to the enzyme active site to produce?
PMC Practice 3
Biology
Enzymes
Elimination Tool:
In 1959, Koshland proposed which of the following?
PMC Practice 1
Biology
Enzymes
Elimination Tool:
If more substrate to already occurring enzymatic reaction is added more enzyme activity is seen because:
Identify the wrong statements.
(a) The substrate binds to active site of enzyme and not fitting into active site
(b) The binding of substrate induces the enzyme to alter its shape
(c) Chemical bonds of substrate break down not to form new enzyme-product complex
(d) The enzyme releases the products of the reaction and runs through catalytic cycle once again
NUMS 2019 Reconduct
Biology
Enzymes
Elimination Tool:
Extreme change in pH results in:
Excessive increase in temperature of medium causes the enzyme molecule to
Optimum temperature for enzymes of human body is:
NUMS 2018
Biology
Enzymes
Elimination Tool:
The following statements are about enzymes:
1. They are globular proteins
2. They can be inhibited by competitive inhibitors
3. They are formed in the smooth endoplasmic reticulum
4. There are only found attached to Plasma membranes in the cell
Which statements are correct for all enzymes?
NTS 2015 DUHS and JSMU
Biology
Enzymes
Elimination Tool:
The rate of reaction is directly proportional to the concentration of an enzyme which statement is incorrect in this respect:
Some enzymes require the presence of a non protein molecule to behave catalytically. An enzyme devoid of this molecule is called a(n):
NTS 2013
Biology
Enzymes
Elimination Tool: