Humber Admissions Practice Test

What feature distinguishes eukaryotic cells from prokaryotic cells?

1. Presence of cell walls

2. Ability to photosynthesize

3. Membrane-bound organelles

4. Size and shape

The correct answer is: Membrane-bound organelles

The distinguishing feature between eukaryotic and prokaryotic cells is the presence of membrane-bound organelles within eukaryotic cells. Eukaryotic cells are characterized by their complex structure, which includes organelles such as the nucleus, mitochondria, endoplasmic reticulum, and Golgi apparatus. Each of these organelles has specific functions, allowing for greater compartmentalization of cellular processes, which enhances the efficiency of metabolic activities. In contrast, prokaryotic cells, such as bacteria and archaea, lack these membrane-bound organelles. Their genetic material is not enclosed within a nucleus; instead, it is found in the cytoplasm in a region called the nucleoid. This fundamental difference in cellular organization is significant, as it contributes to the complexity and specialization found in eukaryotic organisms, including plants, animals, fungi, and protists. Other features listed, like the presence of cell walls, ability to photosynthesize, and size and shape, do not specifically differentiate eukaryotic from prokaryotic cells. For instance, both cell types can have cell walls (though their composition differs), and some prokaryotes can photosynthesize as well. Size and shape can vary widely within both categories