Q: Rounded grains indicate that the minerals eroded from what? Choices: - iron - fossils - recent rock - earlier rock A:
earlier rock

Q: During diastole, what happens to the elastic walls of the arteries? Choices: - they expand - they become hardened - they evolve - they snap back A:
they snap back

Q: Q: What do the muscles of the gastrointestinal tract do? Choices: - break down food - secrete stomach acid - stop digestion - keep food moving A:
A: keep food moving

Question: Q: Carboxylic acids have an acidic hydrogen atom, but esters do not. what do esters have in place of an acidic hydrogen atom? Choices: - synthesis group - carbonation group - crystallization group - hydrocarbon group A:
Answer: hydrocarbon group

*Question*
Q: Vertebrates differ from invertebrates because they lack this? Choices: - legs - head - neck - backbone or a spinal column A:
**Answer**
backbone or a spinal column

Q: Q: What intensifies the response during homeostasis? Choices: - pressure loops - pure loops - negative feedback loops - positive feedback loops A:
A: positive feedback loops