why astronomers theorize that most of the matter in galaxies and clusters of galaxies is dark matter

A fossilized tree killed by a volcano was studied. it had 6.25% of the amount of carbon-14 found in a sample of the same sized tree that is alive today. when did the volcanic eruption take place

Gap junctions (electrical synapses) A. are found only in a few species of animals. B. are far more numerous than chemical synapses. C. have larger pores than voltage-gated ion channels have. D.

Mendel study seven traits in P plants. What are the mono hybrid crosses he made it was between plant with round seeds and plants winkled seeds. What was the conclusion Mendel drew from the F1 generation of the cross? A.

How do genes play a role in cancer progression

How do you write 2-3 paragraphs on evolutionary history/advances from the monerans to protists to fungi?

Which of the following statements about female delinquency based on sexuality is false? Select one: a. Girls who experience an early onset of physical maturity are most likely to engage in antisocial behavior. b.

Ammonia, the major etiologic factor in the development of encephalopathy, inhibits neurotransmission. Increased levels of ammonia are damaging to the body. The largest source of ammonia is from:

What structure on the continental crust is most similar to an ocean ridge? -Plains -Mountain range -Canyon -Plateau

Which is the best way to increase the validity of data in an experiment

What is responsible for converting glucose into a form of energy usable by cells?