What us mitochondria sometimes referred as the what of the cell

Natalie had random hand movements when she was two months old. when she was six months old, she used to grab a block with her whole hand. now at the age of ten months, she can grasp the same block with her thumb and forefinger. this sequence of growth in her hand and finger movements is according to the pattern.

Which describes how weathering and erosion are different? weathering is caused by water. erosion is caused by wind and ice. erosion transports sediments. weathering is a natural process.

Which direction does the energy flow in this energy pyramid ?