Answer:
C. A giant landmass that existed over 250 million years ago
Explanation:
Pangea was the Earth when the continents were mainly together and there was only one "continent".
Answer: Option A) nucleus
Explanation:
Prokaryotic cells lack nuclear envelope, thus the nucleus is absent in Prokaryotic cells.
On the other hand, eukaryotic cells possess membrane bound nucleus and nuclear envelope.
Thus, nucleus is the answer
Pectinate muscles are found on the internal walls of the right and left atria. The correct option is C.
<h3>What are pectinate muscles?</h3>
Pectinate muscles are ridge-like muscle elevations. They are parallel to each other and resemble comb teeth. They can be seen clearly inside the right atrium.
Pectinate muscles are found on the internal walls of the right and left atria.
Thus, the correct option is C.
For more details regarding pectinate muscle, visit:
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Because less animals means less energy that can be used.
