Which one of the choices below can be used to correctly complete the following sentence? "all have a plasma membrane."
a. bacterial cells, but not animal and plant cells,
b. cells
c. plant and bacterial cells, but not animal cells,
d. animal and plant cells, but not bacterial cells,

B. Cells

Explanation:

The plasma membrane is one of the essential structural and functional components of all the cells. It maintains the cell's interior and regulates the entry and exit of substances into and out of the cells. Both prokaryotic and eukaryotic cells have a plasma membrane.

Plasma membrane forms the outer most covering of an animal cell. Plant cells and bacterial cells have a cell wall outside the plasma membrane. Irrespective of the cell type, the plasma membrane is made up of a bilayer of phospholipids with a hydrophobic core. Several proteins are embedded in the lipid bilayer.  

1. (1.2kw)x(15/60hours) = .3kwh --> a

2. (5kw)x(90/60hours)x(8cents/kwh) = $0.60 --> d

3. microwave --> 1200 watts = (1.2kw)x(6/60hours) = .12kwh

coffee-maker --> 900 watts = (.9kw)x(10/60hours) = .15kwh

therefore, it requires more energy for the coffee-maker to do the same amount of work.

so the answer is a.