Answer:
Photosynthetic organisms (plants and/or phytoplankton) are at the bottom of the food chain.
Explanation:
It is true they do have internal fertilization. This is also one of the reason why it is easy to differentiate between a male or a female shark on birth due ot internal fertilization. <span />
The human digestive system can fail if you eat something harmful, and it can break down nutrients, techinically the digestive system can stop working if you get something like Gastoparesis, which stops the movement of food through the digestive system.
<span>Because there is a lack of sufficient oxygen in muscle cells. For muscle cells to convert pyruvate into usable energy (ATP), there must be a sufficient amount of oxygen available to the cells. When there is not, the body has the ability to convert it to lactate which can provide energy when little oxygen is available.</span>
