Please refer to the following art to answer the following questions. 
-The one-way flow of blood in veins is maintained by ________.
Definitions:
Great Depression
A severe worldwide economic downturn that lasted from the late 1920s through the 1930s, leading to mass unemployment and economic hardship.
Deprivation
The state of being deprived of basic needs or comforts, often leading to adverse physical and psychological effects.
West Coast
The westernmost region of the United States, known for its diverse landscapes, significant technological and entertainment industries, and vibrant cultural scenes.
San Francisco
A cultural, commercial, and financial center in Northern California known for its iconic Golden Gate Bridge, steep streets, and historical significance in the technology industry.
Q4: Anaphylactic shock _.<br>A)occurs when blood vessels constrict
Q21: What hormone promotes cell elongation in stems?<br>A)auxin<br>B)cytokinin<br>C)ethylene<br>D)absiscic
Q27: What process dominates the third trimester of
Q33: Why is blood pressure higher during systole
Q35: In most developed countries, overall population growth
Q48: Root nodules in plants such as peas
Q49: What name is given to the seafloor?<br>A)pelagic
Q55: Which group of plants lacks vascular tissue?<br>A)cone-bearing
Q57: A primary immune response is the _.<br>A)immune
Q68: What triggers flowering for plants sensitive to