Problem: Two biologists studied different living creatures. Matt studied protozoa, while his friend Greg studied nematodes and insects.  Which friend studied less about herbivore protozoa?  Hint: Protozoa generally feed by engulfing and digesting other organisms. As consumers, they have various roles in food chains and webs. Some are predators. They prey upon other single-celled organisms, such as bacteria. In fact, protozoa predators keep many bacterial populations in check. Other protozoa are herbivores. They graze on algae. Still others are decomposers. They consume dead organic matter. There are also parasitic protozoa that live in or on living hosts. For example, the protozoan that causes malaria lives inside a human host. For their part, protozoa are important food sources for many larger organisms, including insects and worms.

A: Greg


Problem: Two students learned about respiratory systems in animals. Dana learned more about mammalian lungs, while Barry learned more about the lungs of birds.  Which student learned more about alveoli?  Hint: The lungs of mammals are unique in having alveoli . These are tiny, sac-like structures. Each alveolus is surrounded by a network of very small blood vessels (see Figure below ). Because there are millions of alveoli in each lung, they greatly increase the surface area for gas exchange between the lungs and bloodstream. Human lungs, for example, contain about 300 million alveoli. They give the lungs a total surface area for gas exchange of up to 90 square meters (968 square feet). That’s about as much surface area as one side of a volleyball court!

A: Dana


Problem: 2018 was a very wet year for the Four Corners area,  because of the subtropical ridge, 2019, on the other hand was a dry year influenced by the same weather phenomenon that lacked strength in this year.  Which month of the year was drier, July 2018 or July 2019?  Hint: When the subtropical ridge in the Northwest Pacific is stronger than normal, it leads to a wet monsoon season for Asia.[18] The subtropical ridge position is linked to how far northward monsoon moisture and thunderstorms extend into the United States. Typically, the subtropical ridge across North America migrates far enough northward to begin monsoon conditions across the Desert Southwest from July to September.[19] When the subtropical ridge is farther north than normal towards the Four Corners, monsoon thunderstorms can spread northward into Arizona. When suppressed to the south, the atmosphere dries out across the Desert Southwest, causing a break in the monsoon regime.[20]

A: July 2019


Problem: Last week, an exact clone of Earth appeared next to our current Earth. Scientists have come to call this new planet, Terra. Terra has the exact same cities, civilizations and history as Earth. Scientists are completely baffled as to how this planet exists, but it undeniably does. The only difference between Earth and Terra is that the citizens of Terra output half as many greenhouse gases into the atmosphere as citizens of Earth do.  Does Terra have more or less concentration of carbon dioxide than Earth?  Hint: Current Situation : Currently the heating effect of extra greenhouse gases (since the start of the industrial revolution) is equal to about . Thus the recent period has recorded parallel increases in concentration of carbon dioxide and average global temperature. As more greenhouse gases are put into the atmosphere the temperature will increase further. There are certain effects of a warmer Earth (discussed more in optional section), which could accelerate the process, even if no more greenhouse gases are put into the atmosphere (an unlikely prospect for the foreseeable future).

A:
less