Scientists Hypothesize That Multicellularity Evolved When Groups of Cells Exposed

question 184

Multiple Choice

Scientists hypothesize that multicellularity evolved when groups of cells exposed to an internal environment specialized to perform tasks needed by groups of cells exposed to the external environment, and vice versa.Which biological structures existing today could be used as examples to explain this concept?

• A) The blood cells moving in a fish's circulatory system and the fish's lung tissue
• B) The lining of a snake's intestine and the snake's skin
• C) The bark on an oak tree and the waxy cuticle on an oak leaf
• D) The trachea (airway) in a blackbird's neck and the heart in the blackbird's chest
• E) The whiskers on a cat's face and the fur on the cat's tail

---

Definitions:

Acid

A substance that is a hydrogen ion (proton) donor; acids unite with bases to form salts. Compare with base.

Atomic Mass

The mass of an atom expressed in atomic mass units (amu), essentially equivalent to the number of protons and neutrons in the nucleus.

Atom

The basic unit of a chemical element, consisting of a nucleus of protons and neutrons, with electrons orbiting the nucleus.

Amu

Atomic Mass Unit, a standard unit of mass that quantifies mass on an atomic or molecular scale.