Which nitrogenous base is found in rna but not found in dna?

As a small change in a person's dna can cause a genetic disorder

How do all types of diffusion/passive transport actually ‘work’ without using even the smallest amount of cellular energy?

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.