AP Biology Unit 2 Review+ muscles and Bacteria

Front

What is the fluid mosaic model of cell membranes?

Back

The fluid mosaic model describes the structure of cell membranes as a mosaic of various components (phospholipids, proteins, cholesterol) that move fluidly within the layer, allowing for flexibility and functionality.

Front

What is osmosis?

Back

Osmosis is the movement of water across a selectively permeable membrane from an area of low solute concentration to an area of high solute concentration.

Front

What happens to water levels during osmosis when large molecules cannot pass through the membrane?

Back

The water level will rise on the side with the higher concentration of solute, as water moves to balance the solute concentrations.

Front

How can you reduce interference from red blood cells (RBCs) when isolating white blood cells (WBCs)?

Back

Mix the blood in a hypotonic solution to cause the RBCs to lyse, allowing the WBCs to remain intact.

Front

What is passive transport?

Back

Passive transport is the movement of substances across a cell membrane without the use of energy, typically moving from an area of higher concentration to an area of lower concentration.

Front

Give an example of passive transport without protein assistance.

Back

The movement of carbon dioxide across the plasma membrane is an example of passive transport that does not require proteins.

Front

What are phospholipids?

Back

Phospholipids are molecules that make up the cell membrane, consisting of a hydrophilic (water-attracting) 'head' and two hydrophobic (water-repelling) 'tails'.

Front

What role do membrane proteins play in the cell membrane?

Back

Membrane proteins assist in transporting substances across the membrane, acting as channels or carriers, and also play roles in signaling and structural support.

Front

What is a hypotonic solution?

Back

A hypotonic solution has a lower concentration of solutes compared to the inside of a cell, causing water to enter the cell and potentially leading to lysis.

Front

What is a hypertonic solution?

Back

A hypertonic solution has a higher concentration of solutes compared to the inside of a cell, causing water to leave the cell and leading to shrinkage.