They start as single cell orginisms then they evolve from there.
hope that helps
An organ or group of specialized cells in the body that produces and secretes a specific substance, such as a hormone
The correct answer is by facilitated diffusion.
The procedure of continuous passive transport of ions or molecules through a semi-permeable membrane with the help of particular transmembrane integral proteins is known as facilitated or passive-mediated transport or facilitated diffusion.
It is a modification of osmosis incorporating a proteinaceous channel via which an extracellular solute can enter a cell in the absence of energy.
Answer:
During mitosis, the spindle fibers are called the mitotic spindle. ... Long protein fibers called microtubules extend from the centrioles in all possible directions, forming what is called a spindle. Some of the microtubules attach the poles to the chromosomes by connecting to protein complexes called kinetochores.
Spindle fibers move chromosomes during cell division by attaching to chromosome arms and centromeres. A centromere is the specific region of a chromosome where duplicates are linked. Identical, joined copies of a single chromosome are known as sister chromatids
<u>Brainliest Please!</u>
