B. The Threshold describes the minimum level of stimulus required to ctive a neuron. Hope that helps
Answer : (D)
Explanation: Just as we communicate to each other to initiate a response, cells must also communicate. Of the 7 characteristics of life the characteristic that states a living things respond to their environment most closely relates why cell communication is important and it evolved
Some activities that cell requires energy may include cell division, active transport, protein synthesis etc.
In human, Cells get their energy by the food we eat. The nutrients in the food breaks down into soluble and simple molecules in stomach and small intestine and it is absorbed through the small intestine and assimilated into the cells, becoming part of it, providing the uses for each type of nutrient. And of course, many of them is the energy source.
The DNA is found in the nucleus of the cell
Note that Facilitated diffusion , Active transport and Osmosis are three different ways of transporting substances across the cell surface membrane.
Facilitated diffusion is the movement of a substance from high to low concentration , similar to simple diffusion , but due to the complexity of the cell surface membrane , polar molecules and ions cannot just pass like that , so they pass through specific carrier and channel proteins in the cell surface membrane and so we call it facilitated diffusion.
For Active transport , it's the movement from low to high concentraion using energy from ATP
For Osmosis , it's totally different . You only name osmosis when its all about water . Its the net movement of water from high water potential to low water potential through partially permeable membrane .
If you're doing AS , you'll be familiar with Endosmosis and Exosmosis.
