Chapter 3.1 - 3.8

Proteins of the plasma membrane have many functions. Membrane proteins that provide binding sites for chemical signals are ______ proteins; membrane proteins that anchor one cell to another are _____ proteins and membrane proteins that allow for passage of materials across the plasma membrane are _____ proteins.

receptor, attachment, transport

Some plasma-membrane proteins called ______ are linked to the activation of G protein complexes within cells

recpetor

Identify the two primary components of the plasma membrane.

protein and lipids

Some plasma-membrane proteins called ______ are linked to the activation of G protein complexes within cells.

receptor

Cells communicate via chemical signals which bind to specialized molecules on the plasma membrane surface. These molecules are called _____.

receptor proteins

Allows for cellular identification

Marker molecule

Which are types of proteins that reflect their functions? Select all that apply.

Marker molecules Attachment proteins Receptors Transport proteins

Which are types of proteins that reflect their functions? Select all that apply.

Marker molecules Transport proteins Receptors Attachment proteins

______ soluble molecules can only pass through the membrane by utilizing transport proteins.

Non-lipid

A chemical signal binds to a receptor protein. Which of the following could occur?

Opening of channel protein

Specialized structures which perform specific functions

Organellecel

Where are extracellular substances found?

Outside of the cell

The structure indicated by the black arrow is adhered to the membrane surface. It is a(n) ______.

Peripheral Protein

Identify the molecules that form the plasma membrane.

Phospholipids Proteins Carbohydrates Cholesterol

Outer boundary of the cell through which the cell interacts with the environment

Plasma membrane

The name of the structure that separates the inside of the cell from the environment is the ______.

Plasma membrane

Describe the properties of phospholipids that form the lipid bilayer of plasma membrane.

Polar heads are hydrophilic; nonpolar tails are hydrophobic

Identify functions of attachment proteins. They attach ______.

cells to extracellular material one cell to another cell

Mitochondria are in the space between the cell membrane and nucleus; therefore, they are in the

cytoplasm

Mitochondria are in the space between the cell membrane and nucleus; therefore, they are in the ______.

cytoplasm

The material between the nuclear membrane and plasma membrane is called

cytoplasm

Transmembrane proteins with pores that allow ions and small molecules to pass through the membrane are referred to as ______ proteins.

channel

Integral proteins can arrange themselves in a membrane to create a passageway from one side of the membrane to the other without the need for a specific binding site. This type of protein is called a(n) ______.

channel protein

Ions typically cross the plasma membrane through tube-like passageways called _____.

channel proteins

Ligand-gated ion channels respond to ______ signals.

chemical

The plasma membrane is highly flexible and can change its shape and composition. Therefore, it is described as the ______-mosaic model of the plasma membrane.

fluid

The observation that the plasma membrane of the cell is not static or rigid, but highly flexible and changing has been referred to as the ______.

fluid-mosaic membrane model

A plasma membrane protein is involved in helping to identify its cell to other cells. This protein is acting as a(n) ______.

marker protein

Identify the different types of transport proteins.

ATP powered pumps Carrier proteins Channel proteins

Choose the correct definition of cell metabolism.

All of the chemical reactions that occur in the cell

Identify functions of membrane proteins. Choose all that apply.

Allows cells to identify other cells or molecules Allow for molecules and ions to pass through the cell membrane Serve as a binding site for chemical signals Catalyze chemical reactions Anchor one cell to another

Anchors one cell to another Anchors one cell to another

Attachment proteins

The labeled structure that indicates a peripheral protein of the plasma membrane is letter _____.

B

Identify functions of membrane proteins.

Catalyze chemical reactions Serve as a binding site for chemical signals Allows cells to identify other cells or molecules Allow for molecules and ions to pass through the cell membrane Anchor one cell to another

Ligand-regulated gates respond to ______.

Chemical signals

Identify the molecules that form the plasma membrane.

Cholesterol Proteins Carbohydrates Phospholipids

Substances of similar shapes may bind to the same transport molecule.Transport protein Z will transport molecule G and molecule H that has a similar shape to molecule G.

Competition

Substances with similar shapes may bind to the same transport molecule.

Competition

Fluid which suspends organelles and is found outside of the nucleus and within the plasma membrane

Cytoplasm

A protein on the cell surface in the small intestine breaks the peptide bonds found in dietary proteins to release amino acids. This membrane protein is an example of a (an) ______.

Enzyme

Increase the rates of chemical reactions near the surface of the plasma membrane

Enzymes

Proteins called ______ are specialized proteins that catalyze reactions inside the cells and on the cell's surface.

Enzymes

A selectively permeable membrane is able to allow all substances to pass only some of the time.

False

Large, non-lipid molecules dissolve through the lipid membrane.

False

When a substance is attracted to a watery environment because of its electrical properties, it is often referred to as being hydrophobic.

False

Identify the type of membrane protein that contains large regions of hydrophobic amino acids which allow the protein to insert into the plasma membrane

Integral

Identify the type of membrane protein that contains large regions of hydrophobic amino acids which allow the protein to insert into the plasma membrane.

Integral

Identify properties of a receptor protein.

It is made up of glycoproteins. It attaches to chemical signals. It is made up of proteins.

How do the hydrophilic heads and hydrophobic tails of lipids influence their function?

Lipids will naturally form the bilayer structure of membranes.

Identify the two primary components of the plasma membrane.

Proteins and lipids

Provides sites to which chemical messengers bind

Receptor proteins

Rate of movement of molecules across the membrane is limited by the available transport proteins.

Saturatiom

Substance C is transported by transport protein Y. As the levels of substance C increase, the rate of transport increases but then the rate levels off.

Saturation

The function and rate of function of transport proteins is determined by three factors. Choose those factors

Saturation Competition Specificity

What word(s) describe(s) the ability of the plasma membrane to regulate what molecules enter and leave the cell?

Selectively Permeable

Identify functions of membrane proteins. Choose all that apply.

Serve as a binding site for chemical signals Allow for molecules and ions to pass through the cell membrane Anchor one cell to another Allows cells to identify other cells or molecules Catalyze chemical reactions

A transport protein will only bind to and transport a certain type of substance.

Specificity

Transport protein X will transport molecule A but not molecule B.

Specificity

Choose the characteristics that pertain to transport proteins.

Specificity Saturation Competition

Predict what would happen to a cell if it could not regulate the composition of the intracellular environment (compared to the extracellular fluid).

The cell may not survive under these circumstances.

Allows ions and molecules to pass through the plasma membrane

Transport proteins

Lipid soluble molecules easily pass through the plasma membrane.

True

Receptors can effect a wide variety of changes on the cell membrane including the opening of channel proteins.

True

Some cell receptors are linked to protein complexes called a G protein complex.

True

Some receptor proteins are linked to channel proteins causing them to open when the receptor is bound by a chemical signal or ligand.

True

Some receptor proteins are linked to channel proteins causing them to open when the receptor is bound by a chemical signal or ligand. True false question.

True

When a molecule or substance is repelled by water because of its structure and electrical properties, it is referred to as being hydrophobic.

True

Large, non-lipid-soluble molecules and small pieces of matter are transported across the cell membrane by ______.

Vesicles

One cell can stick to another by using specialized proteins known as ______ proteins.

attachment

Integral proteins, called ____ proteins that bind glucose, electrolytes, and other solutes and transfer them to the other side of the membrane.

carrier

Proteins that move substances across the membrane are called ______.

carrier proteins

All of the chemical reactions that occur within a cell are collectively referred to as

cell metabolism

Substances found outside the cell plasma membrane in the environment are considered

extracellular

Voltage-gated ion channels respond to changes in ______ across the plasma membrane.

electrical charge

Proteins called _______ are specialized proteins that catalyze reactions inside the cells and on the cell's surface.

enzymes

When a substance is attracted to water it is called ______.

hydrophilic

Membrane proteins that are embedded within the lipid bilayer are called ______ proteins and proteins that attach to either the inner or outer surface of the lipid bilayer are called ________.

integral or intrinsic peripheral or extrinsic

Fluids found inside the cell are called ______ fluids.

intracellular

Cytoplasm and nucleoplasm are fluids found inside the cell. These are called ______ fluids.

intracellular; cytosol

When a lipid soluble molecule encounters the lipid bilayer, ______.

it dissolves into the membrane

The transmembrane proteins with pores without gates that allow ions to pass through the membrane are called ion ______.

leak channel

Identify structural features of cells common to most cells.

organelles, plasma membrane, cytoplasm

The ______ encloses and supports the cell contents.

plasma membrane

The name of the structure that separates the inside of the cell from the environment is the

plasma membrane

A membrane that only allows some substances to pass through it but restricts other substances is known as a(n) ________ permeable membrane.

selective

Integral proteins that allow the movement of ions or molecules across the plasma membrane are called ______ proteins.

transport

Fill in the blank question. Ions or molecules are carried from one side of the plasma membrane to the other by integral proteins called ________ proteins.

transport, carrier, channel

A channel opened when the voltage across a membrane changed; therefore, it is a(n) ______ channel.

voltage-gated