Hcg secreted by placenta not the fastest method to detect pregnancy nor it is specific
Astronomers have seen stars forming within a nebular cloud. As the nebular cloud condenses and its own gravitational attraction collapses it, heat and energy build up creating a planet.
Answer: Organs are grouped into organ systems, in which they work together to carry out a particular function for the organism. For example, the heart and the blood vessels make up the cardiovascular system.
Answer:
convergent evolution:
Explanation:
organisms which are not closely related may adapt similarly when exposed to similar environments, thus have similar structures.
