The answer to this is the remains and waste products of plants, animals and other living things organisms.
These are some ways how scientists and engineers develop, use and refine models.
1. Imagine. They have to know what exactly trying to model. They have to imagine and brainstorm what are the things to be considered.
2. Reason. Next, they need to answer the questions brought from their brainstorming. They need to be able to reason out.
3. Calculate and Predict. Once they know it, that's the time they can start modelling and calculate - and predict.
When cells communicate by the signaling process, one cell produces a signaling molecule that must be received by the signal receptor on or in the responding cell. Signaling molecules are often called ligands, a general term for molecules that bind specifically to other molecules (such as receptors).
Answer:
2) End Triassic
Explanation:
End Triassic extinction occurred 201 million years ago. It was caused by the rifting of super continent Pangea. Pangea started to break and drift apart. When North america started to separate from Africa, volcanic activity increased. Lava and a large amount of gas was released into the atmosphere specially carbon dioxide. This led to global warming like condition which ultimately caused extinction of a large number of species.
Explanation:
I thought there were 4 stages total
eggs, larvae,pupae, and adult stage
