Carl and maria joined the cross-country team. they practiced long hours, running for miles every day. when they questioned the never-ending training, coach bill told them that their athletic performance would improve as they worked on endurance, running longer and longer distances. what cellular interactions are the result of their training, allowing for improved athletic performance?

b. the students need more mitochondria for more energy in order to build more muscle mass .  

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.