Answer:
Another specialization of the skeletal muscle is the site where a motor neuron's terminal meets the muscle fiber—called the neuromuscular junction (NMJ). This is where the muscle fiber first responds to signaling by the motor neuron.
D. Neuromuscular Junction
Answer:
Cells in a large multicellular organism communicate with each other by chemical signals. These signals are passed from one cell to another. To receive and respond to a chemical signal, a cell must have a <u><em>receptor</em></u> for that chemical.
Explanation:
To generate a physiological response, all cells in the body have special proteins called receptors. These receptors are involved in detecting a chemical signal and generating a response. The receptors are specific for different kind of chemical signals. For example, a dopamine receptor will bind a dopamine molecule whereas an insulin receptor will be able to bind an insulin molecule. Apart from chemical signals, some cells might also respond to mechanical signals.
The correct option is B.
A multi cellular organisms has many cells which carry out various function and which are organised into tissues, organs and organ system. A unicellular organism on the other hand has only one cell with different cell organelles. Thus, in unicellular organisms, it is the cell organelles that carry out different functions. <span />
Well, nitrogen is the gas that makes up 78% of the earth's atmosphere.
I would guess its in the air that we breathe. I am not really sure. Just basing this answer off of research.