Eukaryotic Cells Quiz

Which of the following best explains why eukaryotic cells compartmentalize their metabolic processes into organelles?

• To increase the cell's surface area-to-volume ratio

• To prevent the mixing of incompatible biochemical reactions

• To enhance the transport of molecules across the plasma membrane

• To reduce the energy consumption of the cell

Mitochondria and chloroplasts have their own DNA and double membranes, which supports which theory regarding their origin?

• Serial endocytosis theory

• The invagination hypothesis

• Endosymbiotic theory

• Symbiotic fusion hypothesis

Which of the following cellular responses best demonstrates the importance of the cytoskeleton in intracellular transport?

• Muscle contraction facilitated by actin and myosin interaction

• Movement of cilia and flagella powered by microtubules

• Distribution of vesicles along microtubules using motor proteins like kinesin and dynein

• Cell division regulated by cyclins and cyclin-dependent kinases

The rapid movement of ions across the plasma membrane during an action potential relies heavily on:

• Diffusion through lipid bilayer

• Facilitated diffusion via carrier proteins

• Gated ion channels

• Endocytosis and exocytosis

Which of the following best explains how signal amplification occurs in a signal transduction pathway?

• Multiple ligands bind to multiple receptors simultaneously.

• One receptor activates multiple G-proteins, which then activate many downstream effectors.

• Receptor proteins increase their binding affinity for the ligand.

• Signal molecules are recycled quickly after their use.