If a scientist were able to measure the exact mass of carbon dioxide and water that entered a plant and the exact mass of sugars produced would the mass be identical? why or why not ?

The mass of carbon dioxide and water that enter a plant doesn't equal the mass of sugar produced by the plant. The products of photosynthesis include both glucose (a sugar) and oxygen:`H_2O + CO_2-> C_6H_12O_6 + O_2`The oxygen, which has mass, is transpired by the plant. According to the law of conservation of matter the mass of the hydrogen and carbon dioxide that produce sugar must equal the mass of both the sugar and oxygen produced.However, there's more going on than just the production of glucose and oxygen. There is water taken up by the plant that is used for the transport of molecules as well as to maintain the turgor pressure in the cells that provides rigidity. Plant growth, reproduction and metabolic processes also utilize some of the molecules used and produced in photosynthesis.

C

Explanation:

When a neuron receives a stimulus, the sodium channels present in the membrane are opened, and therefore Na+ enters the cell in favour of the concentration gradient, so that the membrane potential changes to positive by means of ion exchange, producing depolarization. If this depolarization reaches a certain threshold value, an action potential is generated. The next step is the opening of the potassium channels and the inactivation of the sodium channels, so that the repolarization of the membrane takes place. The sodium channels, will return to the closed state in the hyperpolarization to continue in this state during all the rest potential achieving the action potential to return to -70 mV (repolarization).; until the arrival of a new action potential which produces the activation and opening of the sodium channels, repeating the cycle again and generating a new depolarizing action. This process is part of the synaptic transmission.

So, hyperpolarization is any change in the cell's membrane potential, which makes it more polarized. This means, hyperpolarization is an increase in the absolute value of the cell's membrane potential. Thus, changes in membrane voltage where the membrane potential is more distinctly positive or negative are hyperpolarizations.

During the repolarization period after an action potential, the membrane potential is more negative than when the cell is in "rest period". In the picture, this repolarization period is about 1-2 milliseconds. So, repolarization is the time in which the membrane potential is hyperpolarized with respect to the resting potential.

In the attached figure, part C indicates this repolarization period.