21. on first attachment is secondary succession
22. is the degree of variation of life....
genetic, species or ecosystem within a specific area, system or planet
23. the last one is wrong = )

1 minute of latitude is equal to 1 nautical mile.
Just like an hour of time, there are 60 minutes in a degree of latitude.
Therefore, there are 60 nautical miles in each degree.
Answer:
Food provides the molecules that serve as fuel and building material for all organisms. Plants use the energy from light to make sugars from carbon dioxide and water. ... Organisms Explanation:
Answer:
a. movement can occur both upward and downward in the plant
Explanation:
The phloem loading causes the accumulation of sugars in the sieved elements generating a negative solute potential (quedas), with a drop in water potential (ψw), so water enters the sieved elements increasing the turgor pressure (ψp). With the discharge of phloem in the drain occurs lower concentration of sugars in the screened elements, increases the solute potential, becoming positive, thus the phloem water potential increases and thus the water leaves the conducting vessel. In the specific case of sugar movement in the phloem, it can be stated that this movement can occur both up and down in the plant.
<span>The energy transformation in the sun is primarily the change of nuclear energy to light energy.
More Explainable: </span><span>The sun is said to "burn hydrogen" but what that really means is that near the center of the sun there is enough temperature and pressure to cause the fusion of hydrogen nuclei (protons) into helium nuclei (two protons and two neutrons). The fusion (not fission) reaction energy give off energy in a complex way that includes heat and light. The light works its way out from the center of the sun to the surface and eventually out of the surface into space. That is the sunlight we see as well as some light that is outside our range of vision. The light is electromagnetic energy. </span>