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.
Answer:
Hydrogen and helium.
Explanation:
Extrasolar planets, also called exoplanets are the planets that are placed out of the solar system and it orbits around another star, not the Sun. The planets that are not orbiting around the Sun are made of two easiest elements, and those elements are hydrogen and helium. Extrasolar planets are very strange objects that are not even close to looking like Earth.
The scientific investigation is the systematic approach of the scientists to answer the questions about the world. It is applied almost all of the theories including the Theory of Natural Selection. Darwin's theory of evolution is a result of scientific investigation. In this theory, they investigate by observing the distribution of species.