Cell Structure and Function Flashcards
Distinguish between prokaryotic and eukaryotic cells
Prokaryotic cells lack a nucleus and membrane-bound organelles, while eukaryotic cells have a nucleus and various organelles, making them more complex.
Explain how cell size is limited by surface area-to-volume ratio
Cell size is limited by surface area-to-volume ratio because as a cell grows, its volume increases faster than its surface area, reducing the efficiency of nutrient and waste exchange.
Describe the structure and function of plant and animal cell organelles
Plant and animal cells both have a nucleus, mitochondria, and ribosomes, but plant cells also have chloroplasts and a cell wall for photosynthesis and structure, while animal cells have lysosomes and centrioles for digestion and cell division.
Describe the structure and function of the plasma membrane
The plasma membrane is a phospholipid bilayer with embedded proteins that controls the movement of substances into and out of the cell, providing protection and structural support.
Explain how the plasma membrane allows the passage of substances
The plasma membrane allows substances to pass through via simple diffusion, facilitated diffusion through protein channels, or active transport using energy to move molecules against their concentration gradient.
Distinguish between simple diffusion, facilitated diffusion and active transport
Simple diffusion moves molecules from high to low concentration without energy, facilitated diffusion uses protein channels to help molecules move down their gradient, while active transport requires energy to move molecules against their concentration gradient.
Define the terms isotonic, hypotonic and hypertonic and explain how they affect osmosis
Isotonic solutions have equal solute concentrations, causing no net water movement; hypotonic solutions have lower solute concentrations, causing water to enter the cell, while hypertonic solutions have higher solute concentrations, causing water to leave the cell.
