Unit 3 - Cell Structure and Function

Front

What are the main components of the cell membrane?

Back

The main components of the cell membrane are phospholipids, cholesterol, proteins, and carbohydrates.

Front

What is the function of the polar head in a phospholipid?

Back

The polar head of a phospholipid is hydrophilic (water-attracting) and interacts with the aqueous environment, helping to form the bilayer structure of the cell membrane.

Front

What is the role of ribosomes in a cell?

Back

Ribosomes are organelles that synthesize proteins by translating messenger RNA (mRNA) into polypeptide chains based on genetic instructions.

Front

What distinguishes eukaryotic cells from prokaryotic cells?

Back

Eukaryotic cells have a nucleus and membrane-bound organelles, while prokaryotic cells do not.

Front

Define hypertonic solution in relation to cells.

Back

A hypertonic solution has a higher concentration of solute compared to the inside of a cell, leading to water moving out of the cell and causing it to shrink.

Front

What is the structure of a phospholipid?

Back

A phospholipid consists of a hydrophilic (water-attracting) polar head and two hydrophobic (water-repelling) fatty acid tails.

Front

What is the function of cholesterol in the cell membrane?

Back

Cholesterol helps to stabilize the fluidity of the cell membrane, making it less permeable to very small water-soluble molecules that might otherwise pass freely through.

Front

What are membrane-bound organelles?

Back

Membrane-bound organelles are specialized structures within eukaryotic cells that are enclosed by membranes, such as the nucleus, mitochondria, and endoplasmic reticulum.

Front

What is the significance of the fluid mosaic model?

Back

The fluid mosaic model describes the structure of the cell membrane as a mosaic of various components (lipids, proteins, carbohydrates) that move fluidly, allowing for flexibility and functionality.

Front

How do substances move across the cell membrane?

Back

Substances can move across the cell membrane through passive transport (diffusion, osmosis) or active transport (requiring energy to move against a concentration gradient).