Cells come from pre-existing cells.
Answer:
Answer number 2
Explanation:
So in Geology, Precipitation of rock layers took place over the last hundreds of millions of years...During that process many living organisms have died and are precipitated with the rock layers... Let me explain with an example.
Dinasours went extinct Million years ago while the Dodo bird went extinct a couple of hundred years ago
Would you expect to find Dinasour fossils in newer rock layers or the dodo? lets's say 200m deep? Dodo for sure, Dinasour fossils are waay too old to be found at such shallow deeps that's why fossils in newer layer of rocks are absolutely younger than fossils found at deeper layers
A substance that can be used or prepared for use as food
Fats/Lipids: three fatty acids and a glycerol molecule
Nucleic acids: nucleotides
proteins: amino acids
carbohydrates: monosaccharides, dissaccharides, polysaccharides
The early shape of the fetal brain most resemble a tube. The fetal development starts after conception. After about four weeks the neural tube together with the back is closing. The fetal brain and the spinal cord will develop from the neural tube. Then the other organs and the heart are also starting to form.
