cell :- cell is the basic structural and functional unit of life.
Atom :- everything in the universe is made up of atom.
I’m not 100% sure if this is a scientific theory but I’m going with the big bang theory. The big bang theory is a scientist best guess on how the world came to be. A 2013 map of the background radiation left over from the Big Bang, taken by the ESA's Planck spacecraft, captured the oldest light in the universe. This information helps astronomers determine the age of the universe.
Answer:
The inner wall of the small intestine is covered by numerous folds of mucous membrane called plicae circulares. The surface of these folds contains tiny projections called villi and microvilli, which further increase the total area for absorption.
Explanation:
Hope this helps
Adenosine triphosphate <span>(ATP)
is the energy source for muscle contraction. Myosin is a motor protein that
interacts with actin filaments. When ATP is available, it binds to myosin and
is being hydrolyzed resulting in the conformational changes in myosin. This
leads to the movement of myosin relative to actin filaments.</span>