Describe the role of (A) bacteria fixing nitrogen as they live symbiotically with some plant species, (B) nitrifying bacteria, and (C) denitrifying bacteria in the nitrogen cycle.

Which kind of aquatic ecosystem does the photograph most likely show? a. marsh b. swamp c. lake d. river

In a classic experiment using pea shape, mendel conducted two separate genetic crosses. in the first cross the parent plants were “true breeding” for pea shape; one had round peas ( r )and the other had wrinkled (r). the first cross produced a filial 1 generation of all round peas. in the second cross, mendel bred plants from the filial 1 generation. this cross produced different results. out of approximately 1000 plants, about 75% were round and 25% were wrinkled.

Identify the composition of oceanic and continental crystal rocks.in a model of earth’s interior,where would these rocks appear?