The Microtubule-Binding Protein Patronin Binds to the Minus Ends of Microtubules

question 3

Multiple Choice

The microtubule-binding protein Patronin binds to the minus ends of microtubules at the spindle pole and protects them from the effect of catastrophe factors. If Patronin activity is inhibited by injecting an anti-Patronin antibody into Drosophila melanogaster embryos prior to cellularization, anaphase B is suppressed and the spindles are significantly shorter. Which of the forces (1 or 2) in the following schematic diagram do you think is mostly responsible for anaphase B in this organism at this stage? Does the effect of Patronin inhibition resemble that of kinesin-5 inhibition (I) or overactivation (O) ?

• A) 1; I
• B) 1; O
• C) 2; I
• D) 2; O

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Definitions:

Stimulus

Any event or object in the environment that evokes a response from an organism.

Behavior

The actions or reactions of an organism or system, usually in response to external stimuli, observable and measurable by others.

Frequency

In the context of waves, it refers to the number of cycles of a wave that pass a certain point in a given period of time, typically measured in Hertz (Hz).

Operant Conditioning

Operant Conditioning is a learning process in which the strength of a behavior is modified by reinforcement or punishment.