Neural Control And Coordination

Depolarization of axolemma during nerve conduction takes place because more Na⁺ ions move inside the axon while K⁺ ions move more outside. This movement of ions is essential for generating action potentials, which are the electrical signals that transmit nerve impulses along neurons.

So, the correct option is (B): Na⁺ move inside and K⁺ move more out side.

In eukaryotic cells, there are multiple types of RNA polymerase enzymes responsible for different types of RNA synthesis. The RNA polymerase required in the nucleus for RNA synthesis includes 3. RNA polymerase I is responsible for the synthesis of ribosomal RNA (rRNA), RNA polymerase II is responsible for the synthesis of mRNA (messenger RNA), and RNA polymerase III is responsible for the synthesis of small RNA molecules, including transfer RNA (tRNA) and some small nuclear RNAs (snRNAs). These three RNA polymerases are primarily responsible for RNA synthesis in the nucleus of eukaryotic cells. So, the correct option is (C): 3

Nissl granules were originally thought to be unique structures in nerve cells, but they are now recognized as clusters of ribosomes, which are cellular organelles involved in protein synthesis. These ribosomes play a crucial role in producing proteins necessary for the neuron's function.

So, the correct option is (C): Ribosomes

Neurons have the lowest likelihood of being replaced by new cells. Neurons, which are specialized nerve cells, generally lack significant regenerative capabilities, especially in most areas of the adult human brain and spinal cord. In contrast:

• Osteocytes, responsible for bone maintenance, can be replaced over time, particularly in response to bone injuries or changes.
• Malpighian layer of the skin have a relatively fast turnover rate, as new skin cells continually replace old or damaged ones.
• Liver cells, residing in the liver, possess impressive regenerative potential, allowing the liver to recover from various forms of injury or cell loss.

In summary, neurons are the least likely to be replaced by new cells, while the other cell types mentioned exhibit varying degrees of replacement and regeneration mechanisms.
∴The correct option is (D): Neurons.

One of the examples of the action of the autonomic nervous system is peristalsis of the intestines.
The autonomic nervous system controls involuntary processes in the body, such as the contraction of smooth muscles in the intestines to produce peristalsis. The other options, while involving reflexes and involuntary actions, are typically associated with the somatic nervous system or cranial nerves.

So, the correct option is (D): peristalsis of the intestines

Injury to the abducens nerve can lead to difficulties in moving the affected eye laterally (outward), which can result in strabismus (crossed eyes) and difficulty in coordinating eye movements. It does not directly impact swallowing, tongue movement, or neck movement.

So, the correct option is (A): Movement of the eye ball

Borderline personality disorder is characterized by unstable moods, behavior, and relationships. People with BPD often struggle with regulating their emotions, have difficulties with interpersonal relationships, and may engage in impulsive and self-destructive behaviors. It's important to note that a proper diagnosis should be made by a mental health professional based on a thorough evaluation.

So, the correct option is (B): borderline personality disorder (BPD).