What is the struggle for food, space and other limited rescourses called

Which of the following is a main difference in cell structure between an onion cell and a human cheek cell? a. an onion cell contains one nucleus, whereas a human cheek cell contains two nuclei. b. an onion cell has a cell wall. c. a human cheek cell contains chloroplasts. d. there is no difference between an onion cell and a human cheek cell. you for your.

Blood has traveled from the heart to the toes. which describes the next step of the circulation process?

Which element forms the basis of all organic organisms a carbon b oxygen c hydrogen d nitrogen