Which level of organization involves an organism’s use of the mouth, saliva, teeth, stomach, intestines, liver, and pancreas to break down food? Select one:

Organ.

Cell.

Organ system.

Tissue.

The organ system

Explanation:

All those things you mentioned are part of the organ system, they work together.

water is a polar molecule. a chemical bond is a force of attraction between atoms or ions. bonds form when atoms share or transfer valence electrons. atoms form chemical bonds to achieve a full outer energy level, which is the most stable arrangement of electrons. so, false

explanation:

in h2o molecule, two water molecules are bonded by a hydrogen bond but the bond between two h - o bonds within a water molecule are covalent. the greater the electronegativity difference, the more ionic the bond is. bonds that are partly ionic are called polar covalent bonds. nonpolar covalent bonds, with equal sharing of the bond electrons, arise when the electronegativities of the two atoms are equal.

the answer is b.) hydrogen bonds between bases.