Ascientist discovered a new antibiotic and wanted to know if it would be effective against group a streptococcus bacteria. he designed a test experiment in a lab with ten different cultures of the bacteria. he introduced the antibiotic into five of the cultures, leaving the other five to grow without it. he recorded observations every three hours for a week.

what is the independent variable in this experiment?
a.
the total number of bacteria cultures
b.
the presence of the new antibiotic
c.
the reaction of the bacteria to the antibiotic
d.
the presence of the streptococcus bacteria

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.

i'd say that the moon rock is about 2.2 billion years old.