Isabel is researching the effects of deforestation using online sources. She finds an environmental study on the relationship between deforestation and local weather. Which of the following characteristics should this study have in order for its results to be considered valid?
1. Empirical observations
11. Evidence that can be replicated
III. Outcomes that don't change with new experimentation
OI and 11
O II and III
O I and III
O I only

after receiving a stimus, the sensory receptors send(s) signals to the appropriate area of the body.  

the must be sensory neurons.  

hope its .

unicellular organisms, like bacteria, are able to perform all life functions within one single cell. multicellular organisms need many different types of cells to carry out the same life processes. each of these special types of cells has a different structure that it perform a specific function.