Ques. 1AIPMT 2001
Which cells do not form a layer and remain structurally separate?
- Nerve cells
- Epithelial cells
- Gland cells
- Muscle cells
Answer
(1) Nerve cells
Solution
As per NCERT, the neuron is the structural and functional unit of the neural system.
∵ Epithelial cells (and gland cells, which are specialised epithelial cells) are compactly packed in sheets or layers, and muscle cells are arranged in layers or bundles.
⇒ Neurons are separate cells; one neuron communicates with the next through a synapse, where the membranes are separated by a fluid-filled synaptic cleft.
∴ Nerve cells do not form a layer and remain structurally separate.
Answer: (1)