Question

What factor or factors discovered with electron microscopy distinguished prokaryotic from eukaryotic cells?

1) their size
2) their color
3) the types of their internal structures or organelles
4) their fragility
a) 1
b) 2
c) 3
d) 4
e) 1 and 3

Answer 1

The distinguishing factors of prokaryotic from eukaryotic cells identified with electron microscopy are their smaller size and the lack of internal structures or organelles such as a nucleus.

Step-by-step explanation:

The factor that distinguished prokaryotic from eukaryotic cells using electron microscopy is mainly their internal structures or organelles. Prokaryotic cells generally lack a nucleus surrounded by a nuclear membrane and other membrane-bound organelles, which are characteristic of eukaryotic cells.

Prokaryotes typically range from 0.1 to 5.0 µm in diameter, much smaller than eukaryotic cells which range from 10 to 100 µm. This difference in size is significant, as the size of prokaryotic cells allows rapid diffusion of ions and organic molecules throughout the cell. In contrast, the larger eukaryotic cells have evolved different structural adaptations to facilitate intracellular transport due to their size.

Therefore, the direct answer is e) 1 and 3 - both size and the types of internal structures or organelles are factors that distinguish prokaryotic from eukaryotic cells when observed using electron microscopy.