All Flashcards
Define Cristae.
The folds of the inner mitochondrial membrane, increasing surface area for the electron transport chain.
Define Matrix (in mitochondria).
The space inside the inner mitochondrial membrane where the Krebs cycle occurs.
Define Thylakoids.
Membrane-bound compartments within the chloroplast where light-dependent reactions occur.
Define Stroma.
The fluid-filled space outside the thylakoids in chloroplasts where the Calvin cycle takes place.
Define Semi-permeability (in the context of the plasma membrane).
The characteristic of the plasma membrane that allows some molecules to pass through easily while others require protein channels or pumps.
Define Lysosome.
An organelle containing hydrolytic enzymes that break down cellular waste and debris.
Define Endoplasmic Reticulum (ER).
A network of membranes involved in protein and lipid synthesis, as well as transport within the cell.
What are the key differences between mitochondria and chloroplasts?
Mitochondria: Site of cellular respiration, produces ATP from glucose | Chloroplasts: Site of photosynthesis, produces glucose from light energy.
What are the key differences between Rough ER and Smooth ER?
Rough ER: Contains ribosomes, involved in protein synthesis and modification | Smooth ER: No ribosomes, involved in lipid synthesis and detoxification.
What is the effect of increased surface area (e.g., in cristae or thylakoids)?
Allows for more reactions to occur, increasing cellular efficiency (e.g., more ATP production or light capture).
What happens if the lysosomal membrane is compromised?
Hydrolytic enzymes are released into the cell, potentially causing damage and cellular self-digestion.
What is the effect of a selectively permeable plasma membrane?
It controls what enters and exits the cell, maintaining cellular homeostasis and enabling concentration gradients.