At what stage do we no longer see a nucleus?

What is unique about the members of the group of fungi to which penicillium notatum belongs? they are not important for medicine. they are not made up of hyphae. they are used in fermentation. they lost the reproductive phase.

When coal has reached it hardest, darkest form, it is called select one: 0 a. sub-bituminous b. lignite c. bituminous d. antrhacite next page

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.