Myelin select one: a. is released from a neuron and travels to another neuron. b. consists of layers of lipids and proteins that wrap around an axon. c. is produced in response to bacterial infection. d. is a form of chromatophilic substance that fills schwann cells.

Which of the following best describes the expensive tissue hypothesis? brains require more energy, so the gut had to be reduced, and larger brains and tool use led to higher quality diets. increasing body size means that homo neanderthalensis had to include more fat in its diet. brains require more energy, so the gut had to be reduced as brains got bigger. brains require more fat, so the gastrointestinal viscera (gut) had to expand, and hands were needed to acquire more food.