Plants get their energy from the Sun. animals would then eat the plants and get energy from the plants.
A horn results when glaciers erode three or more aretes, usually forming a sharp edged peak
Answer:
Explanation:
Chlorophyll pigments (mainly chlorophyll a and b) absorb the red and blue spectrum of visible light in the electromagnetic spectrum for photosynthesis. This is why leaves appear green (and occasionally orange) because this visible light portion is not absorbed. The blue light absorbed by leaves ranges between 400 – 450 nm while the red light ranges between 500 nm and 700 nm.
Answer:
The membrane potential of a nerve cell will depolarize if there is an increase in the positive ions inside the cell.
Explanation:
When nerves are in resting potential it is -70mV. In this stage interior of the cell is negatively charged and outside is more positive. When depolarization occurs the inside cell becomes positive.
This is due to the rush of sodium ions into the cell by voltage-gated channels. Now the inside charge is more positive and the chloride ions move out of the cell. Thus outside becomes more negative.
After some time of depolarization stage, potassium ions move out of the cell making the nerve cell again negative. Now the depolarized stage becomes repolarized by the entry of potassium ions.
During depolarization, the potential of the cell is -55mV. When repolarization occurs, it is again -70mV. But the potassium channels are open and some of the potassium ions move out of the cell making the inside environment more negative. This is known as hyperpolarization condition.
This hyperpolarization remains for a short period where action potential can't occur. This period is called the refractory period. Again potassium ions enter into the cell. This results in the resting potential of the neuron again.
