male amphibians including frogs and toads have been plagued by fertilization deformity behavioral abnormalities and sterility biologist from the university of florida investigated whether reproductive problems among population of cane toads bufo marinus are caused by posons from chemicals associated with agriculture the biologists collected local adult cane toads from more than 20 different locations toads where collected from areas close to agriculture both large scale and small scale farms as well as from suburbs that are non agricultural areas based on this study what is / are the control groups 1.male toads collected from the suburbs . 2. male toads collected from areas near large scale farms 3.male toads collected from small scale farms 4. male toads collected from all different sites 5.female toads that were not collected

1. male toads collected from the suburbs

Explanation:

The control group in this case would the male toads collected from the suburbs.

In an experiment, the control group represents a group that receives every other treatment as the experimental group except that of the variable whose effect is the main aim of the experiment.

In observational study, the control group is selected based on a randomly chosen area depending on the variables being examined.

In this case, the researchers are out to investigate whether the reproductive problems observed in the population of cane toads are due to poisons from chemicals associated with agriculture. The control group would be those that are sure not to be a recipient of the poisons associated with agricultural chemicals. Hence, the population of toads close to agricultural sites would form the study group while those far from agricultural sites would represent the control group.

Therefore, the male toads collected from the suburbs would be the control group.

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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preservation because he preserves part of the land and preserves means save

explanation: