Answer:
Brain
Explanation:
The brain has nerve endings that responds to stimulations such as sensory stimulations
Answer:
They release chemical messengers to communicate with cells they may or may not be in direct contact with.
Explanation:
Unicellular organisms such as bacteria or yeast, 'talk' to each other through the release of chemicals. In bacteria, this is known as quorum sensing which allows them to determine the surrounding bacterial population density. In yeast, one of the more popular pathways is known as the mating factor pathway, which allow the organisms to find mates. Whereas, in multicellular organisms (such as humans), this chemical release allows for cell-cell co-ordination which keeps the system functioning correctly.
Phylogenetic
Scientist use a phylogenetic tree to track the evolutionary history of a species.
