Answer:
SA node
Explanation:
The SA node (called the pacemaker of the heart) sends out an electrical impulse. The upper heart chambers (atria) contract. The AV node sends an impulse into the ventricles. The lower heart chambers (ventricles) contract or pump.
Answer: 37. fimbriae. 38. Ductus deferens. 39. Both Cardiac and skeletal muscles. brainliest??
Explanation:
Answer:
(A) a red brick reflects red light and absorbs blue and green light