A leaf consists of many groups of cells that have different properties and perform different
functions. A magnified cross section of a leaf is shown.
Which of these BEST describes a leaf?
a. organelle
b. system
c. organ
d. tissue

Most animal cell membranes have proteins that pump. ions out of the cell and potassium ions into this

Will mark you as ! keiko’s teacher was discussing the theory of endosymbiosis. she asked keiko to mark the organelles in the diagram that most closely resembled prokaryotes. which organelles should keiko mark? * the first image is the question and the second image is some information to you answer the !

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.