Cell Membranes and Cell Structure Lecture Notes

These flashcards cover key concepts related to cell membranes, transport mechanisms, and cell structures based on the lecture notes.

What are the components of a phospholipid molecule?

A phospholipid has a hydrophilic (polar) head and two hydrophobic (non-polar) tails.

What is the function of membrane proteins?

Membrane proteins act as enzymes, transport channels, carriers, receptors for hormones, and recognition proteins.

What is simple diffusion?

Simple diffusion is the process where substances pass between the phospholipid bilayer down their concentration gradient.

What is facilitated diffusion?

Facilitated diffusion is when substances pass through a channel or carrier protein down their concentration gradient.

What is the difference between primary active transport and secondary active transport?

Primary active transport moves substances against their gradient using ATP, while secondary active transport uses the gradient created by primary active transport to move another substance.

What happens to a cell placed in a hypotonic solution?

Water flows into the cell by osmosis, potentially causing it to swell and burst.

What is osmosis?

Osmosis is the diffusion of water through a semi-permeable membrane.

What are the main differences between prokaryotic and eukaryotic cells?

Prokaryotic cells do not have a nucleus and have a single circular DNA, while eukaryotic cells have a nucleus and multiple linear chromosomes.

Describe the structure and function of mitochondria.

Mitochondria are the sites of cell respiration and ATP production.

What is the role of the Na+/K+ pump?

The Na+/K+ pump moves 3 sodium ions out of the cell and 2 potassium ions into the cell to maintain the resting membrane potential.

What does resting membrane potential refer to?

Resting membrane potential refers to the electrical charge difference across the plasma membrane when a cell is not actively transmitting signals.