What does main category mean?

What is an direct description? In humans excess blood glucose is stored in the liver and in muscle tissue in the form of glycogen. Glycogen is a long chain of glucose molecules bonded together. Because of this glycogen is called a? Are humans considered parts of the earth systems? What is the name of a row going across the periodic table? Is 3 pints bigger then 2 quarts? Are carbon fiber doors safe for street use? What is fossil fuels that can be obtained using current technology called? How do Convert 0.0747 inches to mm? At 4 C the volume of 15 g of water was 15 cm3 At 20 C the volume of the same 15 g of water was 15.03 cm3 What effect did the increase in temperature have on the waters density? Why are seeds considered a more effective means of reproduction than spores in a dry environment? How does the statement all for one and one for all apply to large multicelled organisms? What is the effect of increasing the temperature on the solubility of a substance which absorbs heat in forming a solution? What part of the human body consist of keratin? Is Frederick Jones still alive? Who is the current mp for isilo east in the 11th parliament of Kenya? Are yeast an example of amoeba? What structures are not found in the axon? When was Keep the Fire Burning created? Are there hand signs for 8 trigram palm rotation? Who was the first American to sail through the grand canyon?

What does main category mean?