A Level Biology Practice Exam

What role do membrane-bound organelles play in eukaryotic cells?

1. They provide structural rigidity

2. They assist in the cell's metabolic processes

3. They serve as storage for DNA

4. They are only involved in the cell division process

The correct answer is: They assist in the cell's metabolic processes

Membrane-bound organelles are crucial components of eukaryotic cells because they compartmentalize various cellular functions, allowing for increased efficiency and specialization within the cell. Each organelle is surrounded by a membrane that creates a distinct environment, enabling specific metabolic processes to occur in ways that are conducive to their unique functions. For instance, mitochondria are involved in energy production through cellular respiration, while the endoplasmic reticulum is essential for protein and lipid synthesis. The Golgi apparatus is responsible for modifying, sorting, and packaging proteins and lipids for transport. Chloroplasts perform photosynthesis in plant cells. This specialization allows eukaryotic cells to carry out a diverse array of metabolic activities simultaneously, enhancing their overall function and adaptability. In contrast, structural rigidity is primarily provided by components such as the cell wall in plants and structural proteins, rather than membrane-bound organelles. Membrane-bound organelles do not serve as storage sites for DNA; instead, DNA is primarily housed within the nucleus. While certain organelles play roles in cell division—such as centrioles and the mitotic spindle—this is not their sole function, nor do all membrane-bound organelles participate directly in that process.