Answer:
the abiogenesis theory helps us understand
Explanation:
Answer:
Pericardial sac has protective tole
Explanation:
Pericardial sac or pericardium is a fibrous tissue that surrounds the heart. It has two coats:
- the outter coat-parietal pericardium
- the inner coat-visceral pericardium or epicardium which is double-layered and contains pericardial fluid between those two layers (pericardial fluid is necessary as a lubricant for the heart movement).
Besides lubrication, percardium also protects heart from infections, fixes it and limits its movements.
Answer:
D
Explanation:
Prokaryotic are simple cells and do not have nucleus.
Skeletal muscle is under voluntary control