During the S-T segment, what is occurring within cardiac muscle cells?
A. Calcium is entering and potassium is leaving ventricular cells.
B. Potassium is entering atrial cells and sodium is leaving ventricular cells.
C. Sodium channels are beginning to open in ventricular cells and calcium is entering through slow channels in atrial cells.
D. Sodium is rapidly diffusing out of atrial muscle cells.
Answer: A
You might also like to view...
In the first step of the electron transport chain, the coenzymes NADH and FADH2 are oxidized.
Answer the following statement true (T) or false (F)
Asystole means:
A) increased pulse B) lack of heart relaxation C) absence of a heart beat D) increased heart rate
Cushing's disease results from:
A) hyposecretion of insulin. B) hyposecretion of epinephrine. C) hypersecretion of aldosterone. D) hypersecretion of cortisol.
Select the most correct statement concerning skin cancer
A) Squamous cell carcinomas arise from the stratum corneum. B) Melanomas are rare but must be removed quickly to prevent them from metastasizing. C) Basal cell carcinomas are the least common but most malignant. D) Most tumors that arise on the skin are malignant.