A fish may lay many hundreds of eggs. Not all of those baby fish survive long enough to reproduce. Darwin described the battle of these fish to live to a reproductive age as the:

Which of these serves as a reference for comparison during a scientific investigation? a)outcome variable (dependent variable) b) test variable (independent variable) c)control group d)hypothesis

What is an endocrine function? (apex) a.esophageal glands release mucus into the esophagus b.salivary glands release saliva into mouth c.swear glands release sweat to the skin d.the pineal gland releases melatonin into the bloodstream

What did not occur in the proterozoic eon a)the oxygen levels increase greatly in the atmosphere,b)the emergence of the eukarya , c)muti cella’s eukaryotic organisms began to diversify,d)anaerobic bacteria kept thriving with more oxygen