Biology Cell Membrane Structure and Function

Questions and Answers

What does a phospholipid consist of?

A protein and a carbohydrate

A single fatty acid tail

A double layer of carbohydrates

A phosphate group head and two fatty acid chain tails (correct)

What is a hydrophilic head?

The water soluble and charged head of a phospholipid.

What is a hydrophobic tail?

The not water soluble and non charged tail of a phospholipid.

What is the function of a channel protein?

Allows the transport of specific substances across a cell membrane. Signup and view all the answers

What defines an integral protein?

A protein that spans the entire width of the lipid bilayer and protrudes at both sides. Signup and view all the answers

What is an aquaporin?

Proteins that serve as channels for the transfer of water and small solutes across the membrane. Signup and view all the answers

What is a peripheral protein?

A protein that is not embedded in the lipid bilayer but sits on the outside. Signup and view all the answers

What are carbohydrate chains?

Structures that attach to glycoproteins. Signup and view all the answers

What is a glycoprotein?

A protein with an attached carbohydrate. Signup and view all the answers

What is an alpha helix protein?

A protein that extends through the membrane and acts as a channel for nutrients entering the cytoplasm. Signup and view all the answers

What is the role of cholesterol molecules in the bilayer?

Helps maintain the fluid condition of the bilayer. Signup and view all the answers

Study Notes

Phospholipid Structure

Phospholipid consists of a circular phosphate group head and two long fatty acid chain tails.
The hydrophilic head is water-soluble and carries a charge, while the hydrophobic tail is non-water-soluble and uncharged.

Protein Types in the Membrane

Channel proteins facilitate the transport of specific substances across the cell membrane.
Integral proteins span the entire width of the lipid bilayer, protruding on both sides, contributing to membrane structure and function.
Aquaporins act as channels specifically for water and some small solutes, enhancing water transport.
Peripheral proteins are located on the exterior of the membrane and are bound to integral proteins, aiding in cell signaling and structure.

Glycoproteins and Carbohydrate Chains

Glycoproteins consist of a protein with an attached carbohydrate, playing crucial roles in cell recognition and signaling.
Carbohydrate chains are attached to glycoproteins, contributing to the formation of a protective layer on the cell surface.

Specialized Protein Structures

Alpha helix proteins extend through the membrane, functioning as channels for nutrients entering the cytoplasm, and are characterized by their coiled structure.

Role of Cholesterol

Cholesterol molecules help maintain the fluidity of the phospholipid bilayer, preventing it from becoming too rigid or too fluid, thus ensuring proper membrane function.

Description

Explore the intricate components of cell membranes, including phospholipids, various types of membrane proteins, and glycoproteins. This quiz will test your understanding of how these structures contribute to cellular function and interaction. Ideal for biology students studying cell membranes.