Circulatory system
The circulatory system is the transport system for endocrine information. While the nervous system uses neurons, the endocrine chemicals and hormones must circulate through the body via blood vessels. Many glands in your body secrete hormones into the blood.
A dependent variable is how they are recording, measuring or keeping track of the science experiment their doing.
A independent variable is the things/types there using to compare what is the most/least affective in the experiment.
A controlled variable is something that stays the same in the experiment or a group/set used for comparison
Rarefaction in terms of ecology can be defined as a technique used to assess species richness from the results of sampling.
It allows the calculation of richness of a particular species for a given number of individual samples, and these are based on the construction of rarefaction curves.
Hence, the correct answer is: option A-Creating a representative sample
If a cell membrane became impermeable, instead of selectively permeable, the cell would not remain alive, though certain organisms would be able to stay alive longer than others. This is because the cell membrane allows essential molecules and substances such as oxygen into the cell, while allowing harmful substances, like waste, out of the cell.
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