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★ Life Processes Quiz
Structure that prevents blood from flowing backwards in the circulatory system
A. Atrium
B. Vein
C. Ventricle
D. Valve
Select your answer:
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Topics:
Human Eye and Colourful World Blood & Blood Vessels Cardiovascular Pathophysiology Skeletal Tissue Heart Structure and Double Circulation Health and Nutrition Cell Diversity - Organization, Tissues, Plants and Animals Infectious Disease Body System Orthopedics Joints & Movement Differentiation and Division of Human Cells Vision & Hearing Digestive System and Nutrition PHEOther quiz:
Immune System › ViewProteins that help get rid of infections.
A. antibodies
B. skin
C. allergies
Properties of Hair and Scalp › View
Name the two types of melanin (pigment)
A. eumelanin. pheomelanin
B. canities, eumelanin
C. grey, natural
D. pheomelanin, natural