Eukaryotic Cell Structure and Function

1. Do plant cells have mitochondria?
     
   Most cells use ATP as their main form of energy. Most eukaryotic cells, including plant cells, get their ATP from the process of cellular respiration. Cellular respiration takes place in the mitochondria. Following this logic: if plant cells use ATP, and ATP is made in the mitochondria, then plant cells must have mitochondria. Plants need to do something with all that glucose they make!
     
2. Which types of cells have cell walls?
   Plants are not the only organisms whose cells have a wall. Many bacteria and archaea also have cell walls. These walls usually differ slightly, though sometimes majorly, from those commonly seen surrounding plant cells. Just because something has a cell wall does not automatically make it a plant cell.
     
3. What’s the difference between cytoplasm and cytosol?
     
   Everything inside the cell membrane except the nucleus is considered part of the cytoplasm. The cytosol is the gel-like fluid (or solution) in which all of the organelles and cytoskeleton are suspended or dissolved. Note: the common root in cytosol, solution, and dissolve is sol–. The cytosol is part of the cytoplasm.

Prokaryotic Cell Structure and Function

1. Is everything a prokaryote takes in considered "food"? 
    
   At times, you may be tempted to think that anything a prokaryotic cell takes in through its membrane is a food source. They seem to seriously pig out on anything in sight. In reality, only a small fraction of the stuff that enters a prokaryotic cell is used to make ATP. Everything else, including minerals, water, carbon dioxide, and oxygen, are not converted into energy and are therefore not considered "food."
     
2. Do all prokaryotic cells eat food?
     
   No. Many prokaryotic cells are capable of making their own food through the process of photosynthesis. The most common photosynthesizing prokaryotes are called cyanobacteria. These amazing single-celled organisms convert energy from the sun into energy that is used to turn CO₂ into sugar.

Cell Membranes

1. Do plants get their energy from the soil?
   Heck no. Plants, like animals, must have food in order to survive. But unlike most animals, plants make their own food energy through the process of photosynthesis. Plants use this food, in the form of glucose, in the same way that animals use the glucose they eat: it is converted into ATP by the mitochondria.
     
   Plants do, in fact, eat. Their source of food energy? Carbon dioxide (CO₂) in the air. When you really think about it, plants are incredible because they can turn thin air into wood (and fruits, and flowers, and roots) without even thinking about it! Basically, every time you put food in your mouth, you are just eating super-processed air. We just made you feel a little less special, didn't we?
     
2. Is cellular respiration a type of cell "breathing"?
     
   When we talk about cellular respiration, we are not talking about a cell exchanging gases with its environment. Cellular respiration is a term that refers to the process by which glucose and other large carbon-based molecules are converted into ATP in the mitochondria. Be careful not to confuse whole-organism respiration, or breathing, with cellular respiration, which is basically ATP production.