Answer:
1. False
2. True
3. True
4. False
Explanation:
In mammals, the contraction of the heart muscle is caused by pacemaker cells localized within the sinoatrial (SA) node. These cells rhythmically generate slow electrically-induced action potentials due to their slow rate of depolarization. The pacemaker cells generate the action potentials that propagate through the heart and trigger the contraction of myocyte cells (i.e., myocytes simply conduct the action potential waves). The slow depolarization of pacemaker cells occurs during diastole, i.e., during the period of relaxation of the heart muscle.
C. They condense, becoming increasingly compact.
Answer:
O H20 and CH4, but not O2
Explanation:
Compounds consist of multiple elements. O2 is just two oxygen atoms, meaning two atoms from the same element.
<span>B. more energy than radio waves and microwaves.</span><span>
Hope this helps!
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Getting to see and investigate the creatures of the past
