What is involved in muscle contraction?
A. Myofibrils in the muscle shorten and lengthen to make the
muscle contract and extend.
B. Actin and myosin come in and out of the cell to make it thicker
or thinner which changes its length.
C. The gap junctions between the cells pull them closer together
which shortens the muscle.
D. The extra nuclei trigger nerves to stiffen the muscles and make
them shorter.

Describe how alleles and genes are related

Match with o for organic and i for inorganic for each compound

What is a limitation of using a chemical formula, such as c6h1206, to represent a compound? the chemical formula does not show the types of elements that make up the compound. the chemical formula does not show how the atoms are connected to one another the chemical formula does not show the number of atoms of each element in a molecule. the chemical formula does not show the chemical symbols of the elements in the compound