The first heart sound (the "lub" of the "lub-dup") is caused by __________.
opening of the atrioventricular valves
closure of the atrioventricular valves
opening of the semilunar valves
closure of the semilunar valves
closure of the atrioventricular valves
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What is the direct source of the heart sounds in a heart beat?
A) Contraction of ventricles B) Rush of blood through the chambers C) Blood turbulence resulting from valve closure D) Electrical impulse between the SA and AV nodes
Living keratinocytes exfoliate from the epidermis as tiny specks called dander
Indicate whether the statement is true or false
Which of the following is true regarding systemic versus regional anatomy?
A. Systemic anatomy focuses on only one system at a time. B. Regional anatomy focuses on only one system at a time. C. Systemic anatomy focuses on several organ systems. D. Systemic anatomy focuses on several regions of the body.
The epiphyseal plates in long bones are examples of synchondroses.
Answer the following statement true (T) or false (F)