Hatchet fish are able to make themselves virtually invisible in the dark zone. describe two specific aspects of their body design that allows this kind of camouflage.

Their flat bodies and silver sides.

Explanation:

Hatchet fish have line of photophores on their silver side that produce light or bioluminescence. This property helps the fish to swim in water where sunlight do not penetrate. By producing their own light with the same intensity as that of the sunlight , the hatchetfish can make themselves invisible to the predators. This is called as counter-illumination. Also the large flat bodies of these fishes keep them hidden from predators.

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.

many other transport proteins, often called pumps, move materials against a concentration gradient. active transport drives molecules across a membrane from a region of lower concentration to a region of higher concentration. this process, shown in figure 5.1, uses transport proteins powered by chemi- cal energy.