Veins primarily depend upon which of the following forces to return blood to the heart?

A. valves to prevent blood back flow
B. skeletal muscle contraction
C. force of blood entering from the arteries
D. All of the choices apply.


Answer: B

Biology & Microbiology

You might also like to view...

A missense mutation in the ________ gene, a tumor suppressor, results in stomach cancer.

A) HER2 B) RB1 C) E-cadherin D) CML

Biology & Microbiology

When a cell dies before it reaches its next mitosis, it's known as:

a) Mitotic death b) Apoptosis c) Necrosis d) Interphase death

Biology & Microbiology

A(n) ________ is a virus that infects bacterial cells

A) virion B) prion C) bacteriophage D) nucleocapsid E) envelope

Biology & Microbiology

A subtype of cartilage is _____, while a subtype of muscle is _____

smooth; striated cardiac; hyaline elastic; smooth skeletal; cardiac

Biology & Microbiology