
★ Transportation and Excretion Quiz
___ opens and closes the stomata.
A. Guard cells
B. Xylem
C. Roots
D. Phloem
Topics:
Health and Disease Integumentary and Musculoskeletal Systems Medical Careers Neurological Concepts Vascular The Cell Cycle & Cancer Asexual Reproduction Tissues Linked Gene Urinary System Type of Dementia Excretion-Dialysis Maximal Oxygen Consumption (VO2 Max) Chronic Diseases FoodOther quiz: Cosmetology
Normal hair contains percent of the element oxygen.
A. 6
B. 17
C. 21
D. 51