Drawin's experiments are just one way to study phototroprism. A student wants to investigate the effects of phototroprsm in bean plants. She places a light source directly above one plant, at a forty-five degree angle to another, and at a ninety-degree angle from the third. What is the independent variable.

Angle of light source

Explanation:

Independent variable is the variable that the experimenter changes or manipulates in an experiment in order to bring about a measurable response, which is the dependent variable.

In this question, a student wants to investigate the effects of phototropism in bean plants. She places a light source directly above one plant, at a forty-five degree angle to another, and at a ninety-degree angle from the third. This shows that the variable being manipulated (independent variable) is the ANGLE OF THE LIGHT SOURCE.

hormones in blood stream

image: dtc.ucsf.edu

endocrine glands secrete hormones into the blood stream near them; the hormones then travel in our bloodstream until it reaches its destination, called a target cell, in distance parts of the body. in the target tissue, hormones lock onto the target’s plasma membrane, called the receptor site.

i believe the answer is c