How many trophic levels are there in the following food web

Which is a function performed by stem cells in the skin a. replacing lost skin cells b. making cells for the intestines c. growing new organs d. differentiating into brain cells plz apex

You and a group of friends are spending your vacation hiking through the mountains. it is cold in the mountains. you will be expending a lot of energy while hiking and you will need plenty of energy to keep you warm. you should pack foods high in to provide the most energy or kilocalories per gram of food. a) carbohydrates b) lipids (fats) c) proteins d) sugars

What are the three different shapes, or structures, of carbon-based molecules