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.
The answer to this is rolling friction
Once an egg is fertilized by a sperm, a zygote is formed. The zygote divides into multiple cells in a process known as cleavage, triggering the beginning of embryonic differentiation. ... Cells in these three layers will give rise to different parts of the organism. The endoderm eventually becomes the gut.Mar 3, 2011
Answer:
A solid rock becomes soil when it breaks down and combines with water, air, and organic matter. The correct answer would be #3
Explanation:
The reference point = a object used for comparison to determine if something is in motion.
An object is in motion if it changes position relative to a reference point.
You assume that the reference point is stationary, or not moving.
