input: OPTIONS:
- mass migrations
- microevolutions
- spontaneous mutations
- mass extinctions Now, answer this question: Answer the following question given this paragraph: Since life began on Earth, there have been several major mass extinctions. If you look closely at the geological time scale, you will find that at least five major mass extinctions have occurred in the past 540 million years. In each mass extinction, over 50% of animal species died. The total number of mass extinctions could be as high as 20. Q: What events, resulting in death of over half of animal species, have occurred on earth at least five times in the past 540 million years? A:
A:
output: mass extinctions

Answer the following question given this paragraph: Most fungi are multicellular, but some exist as single cells. Single-celled fungi are known as yeasts. Fungi spend most of their life cycle in the haploid state. They form diploid cells only during sexual reproduction. Like the cells of protists and plants, the cells of fungi have cell walls. But fungi are unique in having cell walls made of chitin instead of cellulose. Chitin is a tough carbohydrate that also makes up the exoskeleton (outer skeleton) of insects and related organisms. Q: What is the common term for single-celled fungi? A:

OPTIONS:
- sponges
- mushrooms
- prokaryotes
- yeasts

Answer: yeasts

Problem: OPTIONS:
- Pancreas
- muscles
- heart
- lungs
Q: Answer the following question given this paragraph: This bacterium, called Mycobacterium tuberculosis , causes the disease Tuberculosis (TB). These bacteria usually attack the lungs. If left untreated, the infection can be fatal. Many other illnesses, mild and severe, are also caused by certain types of bacteria. Q: What part of the body does the mycobacterium tuberculosis bacterium usually attack? A:
Answer: lungs

Problem:OPTIONS:
- cell
- droplet
- nucleus
- atom

Answer the following question given this paragraph: An atom is the smallest unit of a chemical element . That is, an atom has all the properties of that element. All atoms of the same element have the same number of protons. Q: What is the smallest unit of a chemical element called? A:
****
A: atom

Answer the following question given this paragraph: The stomach is a sac-like organ at the end of the esophagus. It has thick muscular walls. The muscles contract and relax. This moves the food around and helps break it into smaller pieces. Mixing the food around with the enzyme pepsin and other chemicals helps digest proteins. Q: What is the sac-like organ at the end of the esophagus? A:
OPTIONS:
- rectum
- larynx
- appendix
- stomach
stomach

Answer the following question given this paragraph: Each day, hundreds of weather balloons are launched. Made of a synthetic rubber and carrying a box of instruments, the helium-filled balloon rises up into the sky. As it gains altitude, the atmospheric pressure becomes less and the balloon expands. At some point the balloon bursts due to the expansion, the instruments drop (aided by a parachute) to be retrieved and studied for information about the weather. Q: Why will water balloons launched into the air eventually burst? A:
OPTIONS:
- heat
- momentum
- friction
- expansion

Answer:
expansion