Answer:
skeletal muscle fibres.
Explanation:
skeletal muscle fibres occur in muscles which are attached to the skeleton. They are straited in appearance and under voluntary control.
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Answer:
Cell differentiation
Explanation:
Cell differentiation is common with multicellular organisms. It is the process by which a cell changes from one cell form to another. Cell differentiation makes the change from a zygote to a complex system with different parts.Cells which have been differentiated also becomes specialized. Complex multicellular animals and plants would not be in existence without specialization. This is because cells have specialized functions and each cell is very important to the survival of the organism.
What viral disease now thought to only exist inside a laboratory caused the death of many American Indians after europeans arrived in north American?
smallpox
This is <span>B. The nitrogen base</span>