Answer:
Cell membrane is considered as boundary of the cell.
Explanation:
Cell membrane is the boundary of the cell which is selectively permeable that allows the micro-nutrients, water and gases like oxygen and carbondioxide etc through the process of diffusion. When the water goes inside due to diffusion it is the indicator that there is less quantity of water present inside the cell as compared to the external environment, this phenomena is called hypertonic.
The correct order is:
- Action potential arrives at the axon terminal.
- Calcium ions enter the axon terminal.
- Synaptic vesicles fuse to membrane of axon terminal.
- Acetylcholine is released into the synaptic cleft.
- Acetylcholine binds to its receptors on the junctional folds.
- Junctional folds become depolarized.
- Action potential is initiated on the sarcolemma.
Action potential travels through the membrane of the presynaptic cell causing the channels permeable to calcium ions to open. Ca2+ flow through the presynaptic membrane and increase the Ca concentration in the cell which will activate proteins attached to vesicles that contain a neurotransmitter (e.g. acetylcholine). Vesicles fuse with the membrane of the presynaptic cell, thereby release their contents into the synaptic cleft-space between the membranes of the pre- and postsynaptic cells. Neurotransmitter binds to its receptors on the postsynaptic membrane and its binding causes depolarization of the target cell (muscle cell).
A ribosome is a cell organelle. It functions as a micro-machine for making proteins. Ribosomes are composed of special proteins and nucleic acids. ... Ribosomes are found 'free' in the cytoplasm or bound to the endoplasmic reticulum (ER) to form rough ER.
Hello good evening
Answer will be C.A guess
