Kinks in unsaturated fatty acid tails prevent tight packing of the phospholipid molecules.

The fluid mosaic model describes the plasma membrane as a dynamic structure. Which of the following best explains how the molecular structure of phospholipids contributes to the fluidity of the membrane?

The ability of the cell to be recognized by other cells, such as immune cells.

A researcher treats a cell with a chemical that removes carbohydrates from the external surface of the plasma membrane. Which of the following functions would most likely be impaired?

It prevents the phospholipids from packing too tightly together and solidifying.

Cholesterol is a vital component of mammalian cell membranes. How does cholesterol regulate membrane fluidity as the environmental temperature decreases?

A sequence of nonpolar amino acids that interact with the fatty acid tails.

Integral membrane proteins are embedded within the hydrophobic core of the lipid bilayer. Which of the following amino acid arrangements is most likely found in the transmembrane domain of such a protein?

Peripheral proteins lack hydrophobic regions and do not penetrate the bilayer.

Which of the following describes a key structural difference between peripheral proteins and integral proteins in the plasma membrane?

The molecule contains both a hydrophilic region and a hydrophobic region.

A cell's plasma membrane is described as 'amphipathic' because of the nature of its phospholipids. What does this term mean in the context of membrane structure?

The cell will fail to communicate or adhere correctly to neighboring cells.

A specific toxin binds to and inhibits the activity of glycoproteins on the surface of human respiratory cells. What is the most likely immediate effect on the cell's function?

The hydrophobic interactions between the tails are relatively weak.

In the fluid mosaic model, why are phospholipids and proteins able to move laterally within the plane of the membrane?

It would allow for the facilitated diffusion of glucose across the membrane.

An artificial membrane is created using only phospholipids. It is found to be highly permeable to water but impermeable to glucose. How would adding transport proteins change this?

The hydrophobic fatty acid tails of the phospholipids.

Which component of the plasma membrane is primarily responsible for forming the selective permeability barrier that prevents the free passage of polar molecules?

English

Practice identifying the molecular structure of phospholipids, proteins, cholesterol, and carbohydrates within the fluid mosaic model.

Knowunity

United States of America

AP Biology

Components of the Plasma Membrane

Analyze the ecological and economic motivations behind the initial transfer of goods, people, and diseases between the Old and New Worlds.

AP US History

Origins and Dynamics of the Columbian Exchange

Analyze the initial social and religious encounters between Europeans, Africans, and Indigenous peoples in the colonial Americas.

Introduction to Early Cultural Interactions

Analyze the environmental factors and technological innovations that led to the rise of early states in Mesopotamia, Egypt, and the Indus Valley.

AP World History

Origins of Ancient River Civilizations

Analyze the economic, religious, and political factors that drove European powers to the Americas during the 15th and 16th centuries.

Motivations for European Exploration

Examine the diverse social, political, and economic structures of North American indigenous groups prior to European contact.

Introduction to Native American Societies

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Introduction to Biological Elements of Life

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Introduction to the Spanish Encomienda System

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Origins and Continuity of the Byzantine Empire

Practice identifying the motivations for a weak central government and the specific powers granted to the states under the first U.S. constitution.

AP US Government & Politics

Origins of the Articles of Confederation

Practice the core principles of the APA ethical code including informed consent, debriefing, and the role of Institutional Review Boards.

AP Psychology

Foundations of Ethical Guidelines in Research

Practice identifying partial charges and the chemical basis of hydrogen bond formation between polar water molecules.

Introduction to Water Polarity and Bonding

Practice identifying the four classes of biological macromolecules and the dehydration synthesis reactions that form their covalent bonds.

Introduction to Biological Macromolecules

Practice identifying the monomers and chemical compositions of carbohydrates, lipids, proteins, and nucleic acids in biological systems.

Practice identifying how membrane-bound organelles increase surface area and facilitate specialized chemical reactions in eukaryotic cells.

Introduction to Cell Compartmentalization

Practice identifying fundamental concepts of common ancestry, including homologous structures, vestigial traits, and the fossil record.

Introduction to Evidence of Evolution

Study note

Kylie Brown

Bio 1000 Chapter 2 The Molecules of Cells 

Practice calculating surface area-to-volume ratios and defining how these geometric constraints limit the maximum size of a functional biological cell.

Fundamentals of Cell Size and Surface Area

Practice identifying compartmentalization and the fundamental roles of the nucleus, ribosomes, and the endomembrane system in eukaryotic cells.

Components of the Plasma Membrane

Kartice

Components of the Plasma Membrane

Kartice