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Which of the following statement's are t...

Which of the following statement's are true ?
(a) Saltatory conduction is seen in nonmyelinated nerve fibres
(b) Nissl granules synthesize protein to repair damaged part of neuron
(c) Neurofibrils helps in internal conduction
(d) Trigger zone trigger nerve impulse at base of dendron

A

(a), (b)

B

(a) (c)

C

(b), (c)

D

(c), (d)

Text Solution

AI Generated Solution

The correct Answer is:
To determine which statements are true, let's analyze each statement one by one: ### Step 1: Analyze Statement (a) **Statement:** Saltatory conduction is seen in nonmyelinated nerve fibres. **Analysis:** This statement is false. Saltatory conduction occurs in myelinated nerve fibers, where the action potential jumps from one node of Ranvier to another, speeding up the transmission of the nerve impulse. Nonmyelinated fibers do not have this feature. ### Step 2: Analyze Statement (b) **Statement:** Nissl granules synthesize protein to repair damaged part of neuron. **Analysis:** This statement is true. Nissl granules, which are composed of rough endoplasmic reticulum and ribosomes, are involved in protein synthesis, which is essential for repairing damaged parts of the neuron. ### Step 3: Analyze Statement (c) **Statement:** Neurofibrils help in internal conduction. **Analysis:** This statement is true. Neurofibrils are part of the cytoskeleton of the neuron and play a role in maintaining the structure of the neuron and facilitating internal conduction of impulses within the neuron. ### Step 4: Analyze Statement (d) **Statement:** Trigger zone triggers nerve impulse at base of dendron. **Analysis:** This statement is false. The trigger zone for initiating a nerve impulse is located at the axon hillock, not at the base of the dendron. ### Conclusion: Based on the analysis: - Statement (a) is false. - Statement (b) is true. - Statement (c) is true. - Statement (d) is false. Thus, the true statements are (b) and (c). ### Final Answer: The true statements are: **(b) and (c)**. ---
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