Answer:
One could be in the cell. The cell respires, thus producing carbon dioxide in it. So the concentration builds up in the cell. Diffusion is the net movement of particles from a region of high concentration to a region of low concentration, and the carbon dioxide concentration outside the cell is less, therefore the carbon dioxide molecules moves outs of the cell.
Another scenario is when perfume is sprayed into the air. The perfume particles collides with the air particles (lower or no concentration of perfume). This process goes on and on. This is diffusion since the concentration perfume particles collides with the less concentrated particles of perfume.
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Which part of the neuron below is indicated by the arrow, and what is its function?
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✯ The dendrites carry the electrical impulses from the signal receivers to the cell body.
Sense of smell
Sense of smell is known to
be part of the chemosensory system or chemical senses. It also a warning
system that alert to danger signals such as fire, gas leakage or spoiled food.
Thus, the sense of smell comes from the specialized sensory cells known as
olfactory sensory neurons.
Answer:
The correct answer would be calcium ion and cAMP.
Secondary messengers refers to the intracellular signaling molecules which pass the signals from the receptors located on the surface of the cell to the target molecule present within the cell.
The secondary messengers can be classified into three major class:
- Cyclic nucleotide for example cAMP (cyclic adenosine monophosphate), cGMP (cyclic guanosine monophosphate)
- DAG (diacylglycerol) and IP₃ (inositol triphosphate)
- Calcium ions (Ca⁺⁺)
Hence, from the given options, calcium ion and cAMP would make the correct choice.