Question 14 Systems
A student designs an experiment to demonstrate the presence of openings in the walls of xylem cells in plants. He takes a long stemmed, white chrysanthemeum
(flowering plant) and carefully cuts the stalk halfway up. He places each half of the stalk in a glass cylinder filled with water. Red dye is added to one cylinder, blue
dye is added to the other.
Which two plant systems are interacting in the experiment above?

How does the study of genetic disorders such as pku biologists understand normal alleles?

Scientists are conducting a study on the effectiveness of a new drug on memory loss. they are giving some of the test subjects the new drug to find out if it improves their long-term memory. which are possible limitations of this study? check all that apply. a) test subjects may want to participate in additional experiments. b) test subjects may think they should be paid more. c) test subjects may get bored and want to quit early. d) test subjects may have to travel during the experiment. e) test subjects may have full-time jobs. this is multiple choice. you for the !

Which of the following is the best definition of a eukaryota? a. a one-celled organism that does not have a membrane-bound nucleus b. a one-celled organism that does not have a cell wall c. an organism whose cells each contain a membrane-bound nucleus d. an organism whose cells each have a cell wall