How would the molecule cross the membrane?

Describe how a student should adjust the microscope to see the cells on a slide more clearly?

Explain the source of radioactivity in uranium in earth’s crust by which it produces nuclear radiation

The double bond between a carbon atom and two oxygen atoms (a molecule of carbon dioxide) has two characteristics. what are they? a.an ionic bond is formed between the oxygen and carbon atoms. b.four valence electrons are shared. c.two valence electrons are shared. d.valence electrons are shared between oxygen atoms.