Oxytocin and cholecystokinin are transported through the bloodstream and arrive at the uterus at the same time. oxytocin causes the uterus to contract, whereas cholecystokinin has no effect. why? oxytocin blocks the activity of cholecystokinin. oxytocin is at a higher concentration in the bloodstream than cholecystokinin. oxytocin can diffuse through the plasma membrane of uterine cells, whereas cholecystokinin cannot. oxytocin alters gene expression patterns, whereas cholecystokinin does not. the uterus has receptors for oxytocin, but not for cholecystokinin.

Which of the following is an example of a non-falsifiable hypothesis? a. there is a teacup orbiting the milky way galaxy. b. there is no life on mars. c. the human species started in africa. d. humans cannot live without the amino acid methionine

What is true of sea slugs in these orders

Which statements best describe the differences or similarities between a comparative investigation and an experimental investigation? check all that apply. experimental investigations are best for showing cause-and-effect relationships, while comparative investigations do not necessarily show this type of relationship. comparative investigations are often impractical and unrealistic, while experimental investigations are the most practical and realistic kinds of investigations. comparative investigations allow for the use of a wide range of variables but do not have a control group, while experimental investigations involve variables that can be controlled. both experimental investigations and comparative investigations are designed to answer scientific questions. both experimental investigations and comparative investigations focus on making observations rather than collecting new data.