On a hot day, the upstairs rooms in a house are usually hotter than the downstairs rooms. Why? A. Cool air is less dense than warm air. B. Warm air rises and cool air sinks. C. The upstairs rooms are closer to the sun. D. Heat rises.

How many trophic levels are there in the following food chain? Phytoplankton - shrimp - perch - Pike - osprey

What two things are needed to make a geomagnetic time scale?

The one-toed horse of today steadily evolved from its five-toed ancestor. Which theory of evolution can explain this example?

What is a mass of cell that are growing out of control on one part of the body called?

In the two-stage cooling method, what is the maximum amount of time allowed for stage one (cooling food from 135 to 70 degrees f)

Which of Jupiter's moons is volcanically active? Io Ganymede Europa Callisto

Risk assessment depends on

DNA is genetic material that makes up living things, and folic acid plays an important role in the formation of DNA. Jon wants to study the effect of folic acid on DNA formation in microbes.

Your alien friend from planet Xenon is visiting and wants to learn how to breed pea plants. You show your friend a recent batch of pea plants with purple flowers that you grew by crossing plants that had purple flowers with plants that had white

The green stem ant has three (autosome) chromosomes. During meiosis, chromosome 1 and 3 separate normally, but chromosome 2 homologs do not separate during meiosis I. Meiosis II happens normally. What will the resulting cells of meiosis look like?