Which of the following actions is caused by contraction of skeletal muscle? Select one: a. contraction of the heart b. moving your feet in walking c. movement of food through the digestive tract d. emptying of the urinary bladder e. vasoconstriction

That is true tge cactus as a structural adaptation to its envirinment has it leaves reduced to spines. but this doesnt mean it cant produce food it produces food because of the presence of chlorophyll in its stem

The return of the wolf to yellowstone national park will probably affect the bird population to some degree, not significantly. while wolves will hunt birds when necessary, they prefer to hunt larger prey. the bird population will most likely only be affected when hunting is scarce for the wolves. birds of prey will also probably not be affected as much as other birds who spend more time on the ground hunting for food as the tend to spend more time in the air or in trees since they do not need to stay on the ground for long due to the nature of the way they hunt.