How are the respiratory and circulatory systems connected?
a. they communicate using neuroendocrine cells
b. they connect across synapses
c. they trade oxygen and carbon dioxide
d. they send hormones to each other

How many copies of genes do gametes have?

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 !

For mendels studies, why was it important that his subjects, pea plants, could reproduce quickly and and produce many offspring?