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Benefits of Physical Activity Cancer (Bio II) Bacterial Protein Synthesis Inhbitors Immunisation Child Growth and Development Balanced Diet Macromolecules & Nutrients Biological Organisms Classification Central and Peripheral Nervous System Heart Anatomy Human Anatomy and Physiology - Types of Tissues Anatomy and Physiology- Cardiovascular Sysytem Bacteriology Germs & Diseases Cellular ComponentsOther quiz:
Cardiovascular System › ViewWhich of the following blood vessels has a valve along its length?
A. capillary
B. artery
C. vein
Skel, Musc, Nerv, Circ, Resp › View
Red blood cells are produced in the body and travel through arteries and veins. The circulatory system is able to maintain a relatively constant amount of red blood cells because blood cells are regularly produced by
A. the lymph of the circulatory system
B. the neurons of the nervous system
C. the glands of the endocrine system
D. the bones of the skeletal system