<em>B. Nucleus</em>
Explanation:
The nucleus would be classified as the control center for the cell. Only eukaryotic cells will contain a nucleus and they are surrounded by cytoplasm.
In the cell, a nucleus is very important to have. One of the most important jobs of the nucleus is the holding of genetic material. Genetic material can be either RNA or DNA, but in this case it is DNA. The nucleus holds DNA, which is obviously very important as it stores genes and heredity information.
The nucleus controls all of the important functions of a cell.
Sulfur-containing ores include such sulfides as pyrite, galena, cinnabar, sphalerite, and chalcopyrite, as well as such sulfates as gypsum and barite or heavy spar.
Answer:
Carbon dioxide is transported in three forms. 7% is in the dissolved form in the plasma, 70% is in the form of bicarbonate ions and 20-25% as carbaminohemoglobin, HbCO2.
Explanation:
Transport as bicarbonate ions: 70% of the CO2 is converted into bicarbonate ion and transported in plasma.
Near the tissues, as the partial pressure of CO2 is high so it diffuses into the blood from the tissues. With in the RBC it reacts with water to form carbonic acid i,e. H2CO3. As carbonic acid is unstable, it immediately dissociates into H+ and HCO3- ions. Carbonic anhydrase in the enzyme present with in the RBC which takes part in these reactions. The carbonate ion formed in the RBC quickly diffuses into the plasma and is transported to the lungs in the form of sodium carbonate.
Near the alveoli, the process is reversed that is, bicarbonate ion reenter the RBC and combines with H+ ion to form carbonic acid which then quickly splits into CO2 and H2O in the presence of carbonic anhydrase enzyme. Finally CO2 is diffused from blood to lungs where partial pressure of CO2 is low.
Answer:
number 1: heat from the sun or solar energy