A student drew the following diagram to model the structure of a prairie community. Which level represents short and tall grasses?

A. Level 2
B. Level 1
C. Level 4
D. Level 3

B. Level 1

Explanation:

The prairie community is dominated by the grass and vegetation cover. Thus the lower most trophic level in the prairie ecosystem are the short and tall grasses. They produce major source of biomass for the herbivores of the food chain. They consume the grasses can be designated as primary consumers of the food chain. Also the producers which are grasses which make up the large amount of biomass will provide a source of food for the consumers. They will receive 100 percent energy from the sun and they will utilize 90 percent of it to make their food by the process of photosynthesis.  Only ten percent of energy is transferred to the next trophic level.

the answer that best describes the relative refractory period in the neuron is the resting membrane potential is restored, but concentrations of sodium and potassium are not restored to their original state.

the refractory period is the time during which another stimulus given to the neuron will not lead to a second potential. thus, because na+ channels are inactivated during this time, additional depolarizing stimuli do not lead to new action potentials.  

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hi~~

i would say that hybridization occurs frequently in nature, because there are many types of hybrids that have occurred naturally, such as the mule (male donkey + female horse)