Stem cells are what allow planaria to grow and regenerate as the stem cells can change into any of the cells that make up the planaria.
Answer: space or shelter, ability to reproduce
Explanation:
A model organism is a species that has been widely studied to understand a particular biological phenomena, normally used because they are easy to breed and maintain in a laboratory setting and has certain experimental advantage.
The criteria that Thomas hunt Morgan was looking for include; the model organism should be small in size, easy to keep in the laboratory and also able to produce large number of off springs in a short time.
You are supposed to answer what happens in each phase of meiosis.
Our interconnected neurons help us process different types of information. Synapses are the gaps between neurons. <span>When an impulse reaches the end of one axon, it is now an action potential. This electric signal cannot leap across this gap so as to speak. Special chemicals called neurotransmitters have this role to be possible. The best answer is thus neurotransmitters. </span>