Gastrulation in sea urchins, Drosophila, and Xenopus all begin with a change in cell shape, in which the apical surface of an epithelial sheet contracts. This process is called:

TLS Online TPP Program

#Question id: 12433

#Unit 10. Ecological Principles

The Hubbard Brook watershed deforestation experiment yielded all of the following results except that

TLS Online TPP Program

#Question id: 12434

#Unit 10. Ecological Principles

Nitrifying bacteria participate in the nitrogen cycle mainly by

TLS Online TPP Program

#Question id: 12435

#Unit 10. Ecological Principles

A diagram of a food web, for the following questions. (Arrows represent energy flow and letters represent species.)

In general, the total biomass in a terrestrial ecosystem will be greatest for which trophic level? 

TLS Online TPP Program

#Question id: 12436

#Unit 10. Ecological Principles

A diagram of a food web, for the following questions. (Arrows represent energy flow and letters represent species.)

If this were a terrestrial food web, the combined biomass of C + D would probably be

TLS Online TPP Program

#Question id: 12461

#Unit 10. Ecological Principles

A diagram of a food web, for the following questions. (Arrows represent energy flow and letters represent species.)

If this were a marine food web, the smallest organism might be

TLS Online TPP Program

#Question id: 12462

#Unit 10. Ecological Principles

For most terrestrial ecosystems, pyramids of numbers, biomass, and energy are essentially the same-they have a broad base and a narrow top. The primary reason for this pattern is that