As the ventricles begin to contract, blood pushes against the av valves and closes them, causing
a. blood to pass into the atria.
b. the second heart sound.
c. the first heart sound.
d. a heart murmur.

Mr. wayne is a 38-year-old man with a significant history of elevated cholesterol levels. his father died at age 42 from a massive heart attack secondary to elevated cholesterol and triglycerides, and two of his older siblings are currently taking medications to lower their cholesterol levels. mr. wayne makes an appointment to discuss his risk for hypercholesterolemia. the nurse recognizes that mr. wayne is at risk for familial hypercholesterolemia because this is an autoomal dominant inherited condition. a. describe the pattern of autosomal dominant inheritance. b. mr. wayne asks what chance his children have of developing familial hypercholesterolemia. how should the nurse respond? c. explain the phenomenon of penetrance observed in autosomal dominant inheritance.