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What is the primary characteristic of a competitive inhibitor?
The context states: 'When the inhibitor closely resembles the substrate in its molecular structure and inhibits the activity of the enzyme, it is known as competitive inhibitor.'
How does a competitive inhibitor primarily affect enzyme activity?
The text explains: 'Due to its close structural similarity with the substrate, the inhibitor competes with the substrate for the substrate-binding site of the enzyme.'
Which of the following is an example of competitive inhibition given in the text?
The context provides: 'e.g., inhibition of succinic dehydrogenase by malonate which closely resembles the substrate succinate in structure.'
What happens to the enzyme action when a competitive inhibitor binds to the active site?
The text states: 'Consequently, the substrate cannot bind and as a result, the enzyme action declines.'
Competitive inhibitors are often used for what purpose?
The provided information mentions: 'Such competitive inhibitors are often used in the control of bacterial pathogens.'
If an increase in substrate concentration can overcome the effect of an inhibitor, what type of inhibition is likely occurring?
Competitive inhibition can be overcome by increasing substrate concentration because the substrate will outcompete the inhibitor for the active site. While not explicitly stated to be overcome, the mechanism of direct competition implies this.
Which of the following statements about the normal to a spherical reflecting surface is correct?
According to the NCERT text, 'The normal in this case is to be taken as normal to the tangent to surface at the point of incidence. That is, the normal is along the radius, the line joining the centre of curvature of the mirror to the point of incidence.'
When a parallel beam of light, constituted by paraxial rays, is incident on a concave mirror, the reflected rays:
The NCERT text states, 'The reflected rays converge at a point F on the principal axis of a concave mirror [Fig. 9.3(a)].' This point F is defined as the principal focus for a concave mirror.
For a spherical mirror, the relationship between its focal length (f) and radius of curvature (R) for paraxial rays is given by:
The NCERT text explicitly derives and states this relationship: 'We now show that $f = R/2$, where R is the radius of curvature of the mirror.' This derivation is based on the small angle approximation for paraxial rays.
According to the Cartesian Sign Convention for spherical mirrors, if an object is placed to the left of the mirror, the object distance (u) is typically considered:
The Cartesian Sign Convention usually dictates that distances measured against the direction of incident light (which typically comes from the left) are negative. While the provided excerpt specifically mentions 'principal axis (x-axis) of the mirror/lens are taken as positive', the standard convention (implied by Fig 9.2's left-to-right incident light and positive x-axis to the right) is that object distances for real objects placed to the left are negative, as per general physics conventions for optical instruments. The textbook also mentions 'Distances measured in the same direction as the incident light are positive; those measured in the opposite direction are negative.' If incident light is from left to right, and the pole is the origin, then an object to the left would have a negative distance.
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The bank mixes NEET previous year questions (PYQs) with practice questions, each tagged with its exam appearances where applicable.