Unless a series of sedimentary rock layers has been overturned, which layer is usually the oldest?

the layer on the top. the layer with the most minerals.

The bottom layer.

Explanation: The oldest layers are located at the bottom of the sedimentary rock while the youngest layers are found at the top of the rock. Sedimentary rock most times contains a lot of fossils, they constitute of organisms that have once-lived.

both anaerobic and aerobic respiration use glucose (or other carbohydrates), proteins and lipids to produce atp and nadh. cell uses those energy molecules, obtained from food and   breaks them down during the chemical reactions of respiration. in anaerobic respiration, nadh is regenerated to nad+ by enzymes lactate dehydrogenase (lactate is produced, e.g. in muscle cells) or by alcohol dehydrogenase where ethanol is produced (alcohol fermentation), while in aerobic respiration, electrons from nadh are deposited in the mitochondria to regenerate nad+ (electron transport chain. anaerobic respiration produces 2 atp per molecule of glucose compared to aerobic respiration where about 38 atp molecules are produced.

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