The mitochondrial __ greatly increase the surface area of the inner mitochondrial membrane.
A matrix
B cristae
C grana
D plastids
E lamina
The correct answer and explanation is:
The correct answer is B. cristae.
Explanation:
The mitochondrion is an essential organelle in eukaryotic cells, often referred to as the powerhouse of the cell. It plays a crucial role in energy production, particularly through oxidative phosphorylation during cellular respiration. The inner mitochondrial membrane is the site of the electron transport chain and ATP synthesis, processes that are vital for energy production.
The surface area of the inner mitochondrial membrane is significantly increased by structures known as cristae. Cristae are invaginations or folds of the inner membrane that extend into the mitochondrial matrix. By increasing the surface area, cristae allow for a greater number of protein complexes and enzymes involved in ATP production, maximizing the efficiency of cellular respiration.
The matrix, on the other hand, is the innermost part of the mitochondrion, where the citric acid cycle (Krebs cycle) occurs. While the matrix contains enzymes for metabolic processes, it does not directly increase the surface area for energy production.
The options grana, plastids, and lamina are unrelated to mitochondria. Grana are structures within chloroplasts, responsible for the light-dependent reactions of photosynthesis. Plastids are also a type of organelle found in plant cells, including chloroplasts, chromoplasts, and leucoplasts. The lamina is a term that may refer to the nuclear lamina, a fibrous layer inside the nuclear envelope in eukaryotic cells.
In summary, cristae in the inner mitochondrial membrane are key to enhancing energy production by increasing the membrane’s surface area and providing space for the necessary protein complexes for oxidative phosphorylation.