It’s D i’m pretty sure. correct me if i’m wrong:)
<h3>The blood in the pulmonary artery is going to the heart to collect oxygen, and therefore has a low content of oxygen. So, the blood in the pulmonary artery is a violet colour because it has low oxygen. The blood in the pulmonary vein is oxygen rich, and so it gives a scarlet</h3>
Answer:
1. spontaneously
2. resting potential
3. action potentials
4. pacemaker potentials
5. K+
6. Na+
7. into
8. Ca+
Explanation:
Pacemaker cells (also known as sinoatrial node cells) are cells that generate rhythmic impulses and set the pace for blood pumping in the heart. These cells have the ability to rhythmically depolarize and initiate action potentials. In pacemaker cells, Ca2+ and Na+ levels are higher in the extracellular environment, while K+ concentration is higher intracellularly. The pacemaker action potentials have three phases: 1-depolarization, where membrane potential reaches -40 mV and voltage-gated Ca2+ channels open, 2-repolarization, where voltage-gated Ca2+ channels close and voltage-gated K+ channels open, and finally 3-gradual depolarization, which is caused by the slow influx of Na+ ions.
keep her as comfy as possible till her time comes
