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Many coenzymes have essential chemical components derived from:
The NCERT text states: 'The essential chemical components of many coenzymes are vitamins, e.g., coenzyme nicotinamide adenine dinucleotide (NAD) and NADP contain the vitamin niacin.'
Which of the following is true regarding the catalytic activity of an enzyme lacking its cofactor?
The NCERT text clearly states: 'Catalytic activity is lost when the co-factor is removed from the enzyme which testifies that they play a crucial role in the catalytic activity of the enzyme.'
The maximum velocity ($V_{ ext{max}}$) of an enzymatic reaction is reached when:
The NCERT text explains: 'The reaction ultimately reaches a maximum velocity ($V_{ ext{max}}$) which is not exceeded by any further rise in concentration of the substrate. This is because the enzyme molecules are fewer than the substrate molecules and after saturation of these molecules, there are no free enzyme molecules to bind with the additional substrate molecules.'
An active site of an enzyme is best described as:
According to the NCERT text: 'One such pocket is the ‘active site’. An active site of an enzyme is a crevice or pocket into which the substrate fits. Thus enzymes, through their active site, catalyse reactions at a high rate.'
Kinetic studies of an enzyme show that its rate of reaction doubles for every 10°C rise in temperature within its optimal range. This is primarily influenced by:
The NCERT text states: 'Rates of physical and chemical processes are influenced by temperature among other factors. A general rule of thumb is that rate doubles or decreases by half for every 10°C change in either direction.'
What is the protein portion of an enzyme, which becomes catalytically active only when associated with non-protein constituents, called?
The NCERT text defines it as: 'In these instances, the protein portion of the enzymes is called the apoenzyme.'
The enzymatic pathway of substrate (S) transformation into product (P) always goes through:
The NCERT text emphasizes: 'There is thus, an obligatory formation of an ‘ES’ complex. E stands for enzyme. This complex formation is a transient phenomenon.'
Which of the following statements best describes the relationship between temperature and heat?
According to the NCERT text, 'Heat is a form of energy that flows between a body and its surrounding medium by virtue of temperature difference between them. The degree of hotness of the body is quantitatively represented by temperature.' This clearly distinguishes heat as energy transfer due to temperature difference, and temperature as a measure of the degree of hotness.
An ideal gas equation can be written as $PV = \mu RT$. What does $T$ represent in this equation?
The NCERT text states: 'The ideal gas equation connecting pressure (P), volume (V) and absolute temperature (T) is : $PV = \mu RT$'. Therefore, T represents absolute temperature, which is typically measured in Kelvin.
Which of the following phenomena is explained by the unreliability of our temperature sense?
The text states: 'We can perceive temperature by touch. However, this temperature sense is somewhat unreliable and its range is too limited to be useful for scientific purposes.' The scenario where two objects at the same temperature feel different to touch is a classic example of this unreliability, as it depends on their thermal conductivity, not just their actual temperature.
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The bank mixes NEET previous year questions (PYQs) with practice questions, each tagged with its exam appearances where applicable.