You are presented with the quiz "Macroevolution above the level of the species happens over what" But you don't know the answer, so you turn to your teacher to ask for hints. He says that "macroevolution is evolution over geologic time above the level of the species" and "dates are provided for the recognized eras and periods of geologic time". So, what's the best answer to the question?

OPTIONS:
- seasons
- eras
- scale
- Earth
- plates
- days
- minutes
- years

Answer: eras

You are presented with the quiz "scraping oneself on a contaminated object may cause" But you don't know the answer, so you turn to your teacher to ask for hints. He says that "scraping oneself on a contaminated object may cause infection" and "infection often causes death". So, what's the best answer to the question?

OPTIONS:
- deadly
- Injury
- blood
- rabies
- Herpes
- death
- mildew
- disease

Answer: death

You are presented with the quiz "What do Echinoderms lack?" But you don't know the answer, so you turn to your teacher to ask for hints. He says that "echinoderms lack respiratory and excretory systems" and "lung mechanics and gas exchange are topics during study of the respiratory system". So, what's the best answer to the question?

OPTIONS:
- Lungs
- Mass
- oxygen
- eardrum
- gills
- ovaries
- Organs
- Bodies

Answer: Lungs

You are presented with the quiz "A response to what occurs when many muscles contract a little at once?" But you don't know the answer, so you turn to your teacher to ask for hints. He says that "shivering occurs when many muscles contract a little bit all at once" and "another response to cold is shivering". So, what's the best answer to the question?

OPTIONS:
- heat
- cold
- sweat
- pain
- forces
- stress
- comfort
- motion

Answer:
cold