What part of the cell surrounds the cell and allows molecules in and out?

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.

Describe the layers of the suns atmosphere?

Which of the following types of reactions would decrease the entropy within a cell? a. dehydration reaction, b. hydrolysis, c. respiration, d. digestion, e. catabolism.