p.38
Composition of the Plasma Membrane
What type of substances diffuse through lipid membranes?
Lipid soluble substances.
p.34
Selective Permeability and Membrane Function
What happens at equilibrium in a diffusion process?
The concentration becomes uniform.
p.15
Structure of the Cell Membrane
Is the inside of the cell membrane the same as the outside?
No, the inside and outside of the cell membrane have different compositions and properties.
p.37
Selective Permeability and Membrane Function
What is the permeability of the membrane to water?
The membrane is permeable to water.
p.22
Selective Permeability and Membrane Function
What role do channel proteins play in the cell membrane?
They facilitate the transport of substances across the membrane, often down their concentration gradient.
p.5
Types of Membrane Transport: Active vs Passive
What is primary active transport?
A process that uses ATP to move ions or molecules against their concentration gradient.
p.71
Glycocalyx and Cell Recognition
What is the significance of your appreciation?
It acknowledges the effort and understanding in communication.
p.40
Mechanisms of Carrier-Mediated Transport
What is facilitated diffusion?
A process that allows substances to cross membranes with the assistance of special proteins.
p.27
Selective Permeability and Membrane Function
What type of molecules cannot easily pass through impermeable membranes?
Ions and hydrophilic molecules.
p.27
Selective Permeability and Membrane Function
What characteristic of the membrane affects the passage of ions and hydrophilic molecules?
The hydrophobic nature of the membrane.
p.16
Composition of the Plasma Membrane
How do plasma proteins function as receptors?
They bind to specific molecules to initiate a response.
p.16
Composition of the Plasma Membrane
What role do plasma proteins play as enzymes?
They catalyze biochemical reactions.
p.60
Mechanisms of Carrier-Mediated Transport
What is the primary mechanism for the faster transport of d-glucose across the plasma membrane of adipose cells in the presence of insulin?
Carrier-mediated transport of glucose.
p.49
Selective Permeability and Membrane Function
Which type of substances are typically restricted from passing through the lipid bilayer?
Water-soluble substances.
p.38
Selective Permeability and Membrane Function
What is diffusion?
The movement of substances from an area of higher concentration to an area of lower concentration.
p.37
Selective Permeability and Membrane Function
Is the membrane permeable to albumin?
No, the membrane is not permeable to albumin.
p.12
Composition of the Plasma Membrane
What are the two types of proteins found in the cell membrane?
Peripheral proteins and integral proteins.
p.23
Glycocalyx and Cell Recognition
What is the function of cell recognition proteins?
They help cells identify and communicate with each other.
p.10
Structure of the Cell Membrane
What is the primary function of the plasma membrane?
To separate the inside from the outside and regulate exchange between them.
p.69
Mechanisms of Carrier-Mediated Transport
What is facilitated diffusion?
The passage of water-soluble solutes and ions through a hydrophilic pathway created by integral proteins.
p.13
Glycocalyx and Cell Recognition
What contributes to the uniqueness of each individual's cells?
The diversity of carbohydrate chains in the glycocalyx.
p.30
Selective Permeability and Membrane Function
How selective are channel and carrier proteins?
Both are highly selective in the types of molecules or ions that are allowed to cross the membrane.
p.51
Types of Membrane Transport: Active vs Passive
What is the role of ATPases in primary active transport?
They act as pumps to move substances against their concentration gradient.
p.70
Properties of Epithelial Cells in Solute Movement
How does the polarized organization of epithelial cells affect solute movement?
It ensures directional movement of solutes and water across the epithelial layer.
p.54
Types of Membrane Transport: Active vs Passive
What happens to the other molecule(s) during secondary active transport?
They are dragged from low to high concentration (uphill transport).
p.47
Regulation of Cell Volume Under Osmotic Stress
What is the function of afferent neurons in a negative feedback system?
They transmit signals to the brain about changes in the environment.
p.55
Mechanisms of Carrier-Mediated Transport
What role do symporters play in secondary active transport?
They transport two different molecules in the same direction across the membrane, using the energy from one molecule's gradient.
p.42
Types of Membrane Transport: Active vs Passive
What characterizes active transport?
It requires energy to move substances against their concentration gradient.
p.45
Selective Permeability and Membrane Function
What is the relationship between simple diffusion and flux?
There is a linear relationship between simple diffusion and flux.
p.40
Mechanisms of Carrier-Mediated Transport
In which direction does facilitated diffusion occur?
From higher concentration side to lower concentration side.
p.17
Composition of the Plasma Membrane
What is Glycosylphosphatidylinositol (GPI)?
A glycolipid that anchors proteins to the cell membrane.
p.22
Selective Permeability and Membrane Function
What types of substances typically pass through channel proteins?
Ions and small polar molecules.
p.50
Selective Permeability and Membrane Function
How does membrane thickness affect solute permeability?
Thicker membranes generally reduce permeability.
p.74
Selective Permeability and Membrane Function
What effect does increasing the thickness of the membrane have on diffusion?
It decreases the rate of diffusion.
p.5
Regulation of Cell Volume Under Osmotic Stress
What mechanisms do cells use to regulate their volume under osmotic stress?
They may use ion channels, transporters, and osmolytes to adjust their internal solute concentration.
p.60
Mechanisms of Carrier-Mediated Transport
What role does insulin play in the transport of glucose in adipose cells?
It increases the speed of d-glucose transport across the plasma membrane.
p.68
Mechanisms of Carrier-Mediated Transport
What role does the Na/K+ - ATPase play in glucose transport?
It helps maintain the Na+ gradient necessary for glucose transport.
p.26
Selective Permeability and Membrane Function
What must be balanced regarding charges inside and outside the cell?
The number of positive and negative charges.
p.31
Structure of the Cell Membrane
How do proteins contribute to cell membrane structure?
They are integral and peripheral components that help maintain the membrane's integrity and functionality.
p.73
Impact of ATP on Membrane Transport Processes
What is the correct answer to the question regarding transport processes ceasing due to cyanide?
D. All of these options are correct.
p.31
Types of Membrane Transport: Active vs Passive
What is the significance of protein folding?
Proper folding is essential for protein function and determines how proteins interact with other molecules.
p.55
Mechanisms of Carrier-Mediated Transport
What role do antiporters play in secondary active transport?
They transport two different molecules in opposite directions across the membrane, utilizing the energy from one molecule's gradient.
p.61
Mechanisms of Carrier-Mediated Transport
Is glucose transported via receptor-mediated endocytosis?
No, glucose is not transported this way.
p.1
Role of Ion Channels: Voltage-Gated vs Ligand-Gated
What is the role of ion channels in the cell membrane?
To facilitate the movement of ions across the membrane.
p.19
Composition of the Plasma Membrane
What is an integrin?
An adhesion molecule that attaches the cell to the extracellular matrix.
p.34
Selective Permeability and Membrane Function
What is diffusion in the context of dye molecules?
The movement of dye molecules down their concentration gradient.
p.45
Types of Membrane Transport: Active vs Passive
How does facilitated diffusion via uniporters compare to simple diffusion?
Facilitated diffusion via uniporters is faster than simple diffusion but is saturable.
p.38
Selective Permeability and Membrane Function
In which direction does diffusion occur?
From higher concentration to lower concentration.
p.45
Mechanisms of Carrier-Mediated Transport
What is inhibited in Lambert-Eaton syndrome due to blocked Ca2+ channels?
Ca2+-dependent exocytosis of vesicles filled with acetylcholine (Ach).
p.45
Selective Permeability and Membrane Function
What neurotransmitter is affected in Lambert-Eaton syndrome?
Acetylcholine (Ach), which is needed for muscle contraction.
p.24
Selective Permeability and Membrane Function
Which substances can easily pass through the cell membrane?
Oxygen, carbon dioxide, and alcohol.
p.22
Types of Membrane Transport: Active vs Passive
What is a channel protein?
A type of protein that allows specific ions or molecules to pass through the cell membrane.
p.40
Mechanisms of Carrier-Mediated Transport
What role do carrier proteins play in facilitated diffusion?
They help transport substances across the cell membrane without using energy.
p.27
Selective Permeability and Membrane Function
Which type of molecules can easily pass through impermeable membranes?
Small and hydrophobic molecules.
p.39
Types of Membrane Transport: Active vs Passive
What is facilitated diffusion?
A process that requires a carrier to transport molecules across a membrane.
p.72
Types of Membrane Transport: Active vs Passive
What is active transport?
The movement of substances against their concentration gradient using energy.
p.50
Selective Permeability and Membrane Function
What factors determine the permeability of a solute across a lipid bilayer membrane?
Molecular radius, oil/water partition coefficient, and membrane thickness.
p.17
Composition of the Plasma Membrane
What is the primary function of GPI in the cell membrane?
To serve as an anchor for proteins.
p.72
Types of Membrane Transport: Active vs Passive
What is secondary active transport?
A process that uses the energy from the electrochemical gradient created by primary active transport.
p.50
Selective Permeability and Membrane Function
Which solute characteristics contribute to higher permeability across a lipid bilayer?
Smaller molecular radius and higher oil/water partition coefficient.
p.12
Composition of the Plasma Membrane
What are glycolipids?
Phospholipids with carbohydrate chains.
p.39
Mechanisms of Carrier-Mediated Transport
What type of particles can diffuse through carrier proteins in facilitated diffusion?
Larger particles, such as glucose.
p.69
Types of Membrane Transport: Active vs Passive
What processes allow macromolecules to cross the plasma membrane?
Endocytosis and exocytosis.
p.12
Composition of the Plasma Membrane
What are glycoproteins?
Proteins that have carbohydrate chains attached.
p.49
Selective Permeability and Membrane Function
What determines the ability of substances to move in and out of the cell?
The lipid bilayer of the plasma membrane.
p.13
Glycocalyx and Cell Recognition
What is one function of the glycocalyx?
Cell-to-cell recognition.
p.69
Selective Permeability and Membrane Function
What happens during passive movement of a solute across a membrane?
It dissipates the gradient and reaches equilibrium, resulting in no net movement of solute.
p.74
Selective Permeability and Membrane Function
Which factor increases the rate of diffusion of a particle across a membrane?
C. The area of the membrane increases.
p.24
Selective Permeability and Membrane Function
What type of substances are impermeable to the cell membrane?
Usual water-soluble substances, such as ions and glucose.
p.72
Mechanisms of Carrier-Mediated Transport
What is facilitated diffusion?
The movement of substances across a membrane via carrier molecules.
p.39
Selective Permeability and Membrane Function
In which direction do molecules move during facilitated diffusion?
From higher concentration to lower concentration.
p.13
Glycocalyx and Cell Recognition
What role does the glycocalyx play in cell adhesion?
It facilitates cell-cell adhesion.
p.16
Composition of the Plasma Membrane
What is the significance of transport by plasma proteins?
They help in the movement of substances across the membrane.
p.23
Glycocalyx and Cell Recognition
What role do cell recognition proteins play in the immune system?
They help the immune system distinguish between self and non-self cells.
p.54
Types of Membrane Transport: Active vs Passive
Does secondary active transport directly utilize energy?
No, it depends on primary active transport.
p.51
Mechanisms of Carrier-Mediated Transport
What are the two types of transporters involved in primary active transport?
Uniporter and biporter (symport or antiport).
p.30
Selective Permeability and Membrane Function
What is the role of concentration gradient in channel protein function?
It allows the movement of water and selected ions or molecules.
How does the concentration of ions vary across the cell membrane?
It varies widely between the inside and outside of the cell.
p.47
Regulation of Cell Volume Under Osmotic Stress
What role do effectors play in a negative feedback system?
They carry out the response to restore balance.
p.1
Structure of the Cell Membrane
What is the primary function of the cell membrane?
To protect the cell and regulate what enters and exits.
p.4
Mechanisms of Carrier-Mediated Transport
What is the main difference between carrier-mediated transport systems and channels?
Carrier-mediated transport involves specific binding and conformational changes, while channels allow passive movement of molecules through a pore.
p.42
Types of Membrane Transport: Active vs Passive
What are the two main types of membrane transport systems?
Active transport and passive transport.
p.33
Types of Membrane Transport: Active vs Passive
What energy drives the process of diffusion?
The energy of normal kinetic motion of matter.
p.61
Selective Permeability and Membrane Function
Can glucose pass through the cell membrane via simple diffusion?
No, glucose molecules are too large for significant simple diffusion.
p.14
Structure of the Cell Membrane
How do phospholipids behave in the cell membrane?
They are fluid and mobile.
p.72
Selective Permeability and Membrane Function
How does water move across a plasma membrane?
C. simple diffusion through membrane channels.
p.22
Types of Membrane Transport: Active vs Passive
Are channel proteins involved in active or passive transport?
They are primarily involved in passive transport.
p.17
Composition of the Plasma Membrane
What type of molecules does GPI typically anchor?
Proteins, particularly those involved in signaling.
p.49
Selective Permeability and Membrane Function
Which type of substances can easily pass through the lipid bilayer?
Lipid-soluble substances.
p.51
Types of Membrane Transport: Active vs Passive
What is the main characteristic of primary active transport?
Moves substances against their concentration gradient.
p.10
Composition of the Plasma Membrane
What is the basic structure of the plasma membrane?
A phospholipid bilayer with embedded proteins.
p.69
Role of Ion Channels: Voltage-Gated vs Ligand-Gated
How is facilitated diffusion of small ions mediated?
By specific pores and ion channel proteins.
p.64
Types of Membrane Transport: Active vs Passive
What is facilitated diffusion?
A process that allows substances to cross membranes with the assistance of special proteins.
p.48
Structure of the Cell Membrane
What characteristic of a cell membrane increases membrane fluidity?
E. Unsaturated phospholipid content.
p.70
Types of Membrane Transport: Active vs Passive
What is the role of active transport in solute movement?
It uses metabolic energy to move solutes against gradients, preventing a state of equilibrium.
p.55
Types of Membrane Transport: Active vs Passive
What is secondary active transport?
A type of transport that uses the energy from the electrochemical gradient created by primary active transport to move substances against their concentration gradient.
p.48
Structure of the Cell Membrane
What effect do saturated phospholipids have on membrane fluidity?
They decrease membrane fluidity.
p.59
Selective Permeability and Membrane Function
What happens to sodium (Na) levels in lactose intolerance?
Sodium (Na) levels increase.
p.55
Mechanisms of Carrier-Mediated Transport
How does the sodium-potassium pump relate to secondary active transport?
It creates the sodium gradient that is used by secondary active transporters to move other substances into the cell.
p.70
Regulation of Cell Volume Under Osmotic Stress
How do cells regulate their volume?
By moving solutes in or out to drive osmotic entry or exit of water.
p.1
Selective Permeability and Membrane Function
What is selective permeability?
The ability of the cell membrane to allow certain substances to pass while blocking others.
p.41
Mechanisms of Carrier-Mediated Transport
How does secondary active transport utilize the Na+ gradient?
The inwardly directed Na+ gradient is used to drive glucose uptake from the intestine.
p.14
Structure of the Cell Membrane
What do membranes structurally define?
Cells, nucleus, and organelles.
p.5
Types of Membrane Transport: Active vs Passive
How does secondary active transport differ from primary active transport?
It uses the energy from the movement of one substance down its concentration gradient to drive the movement of another substance against its gradient.
p.69
Types of Membrane Transport: Active vs Passive
What is simple diffusion?
The passage of lipid-soluble solutes across the plasma membrane through the lipid bilayer.
Which ions are higher in concentration outside the cell?
Na+ (sodium) and Cl- (chloride).
p.25
Glycocalyx and Cell Recognition
How does the glycocalyx contribute to cell adhesion?
The glycocalyx of some cells attaches to the glycocalyx of other cells, thus attaching cells to one another.
p.48
Structure of the Cell Membrane
How does body cold stress affect cell membrane fluidity?
It decreases membrane fluidity.
p.54
Types of Membrane Transport: Active vs Passive
In secondary active transport, how does one molecule move?
Down its concentration gradient (high to low).
p.25
Glycocalyx and Cell Recognition
What happens when hormones bind to the glycocalyx?
It activates attached internal proteins that, in turn, activate a cascade of intracellular enzymes.
p.46
Mechanisms of Carrier-Mediated Transport
What role does Ca²⁺ play in neurotransmitter release?
It is essential for the exocytosis of vesicles filled with neurotransmitters.
p.1
Composition of the Plasma Membrane
What is the basic structure of the cell membrane?
A phospholipid bilayer with embedded proteins.
p.61
Mechanisms of Carrier-Mediated Transport
Where does exchange transport of glucose occur?
In the kidneys, but not in adipose tissue.
p.59
Selective Permeability and Membrane Function
What happens to sodium (Na) levels when glucose levels increase?
Sodium (Na) levels decrease.
p.61
Selective Permeability and Membrane Function
Can a small amount of glucose diffuse across the membrane?
Yes, but it is minimal and requires adequate time.
p.5
Properties of Epithelial Cells in Solute Movement
What properties of epithelial cells are necessary for directional movement of solutes and water?
Polarity, tight junctions, and specific transport proteins.
p.54
Types of Membrane Transport: Active vs Passive
What does secondary active transport ultimately depend on?
Primary active transport.
p.46
Mechanisms of Carrier-Mediated Transport
What is Lambert-Eaton syndrome?
A neurologic condition caused by autoantibodies that block Ca²⁺ channels on presynaptic motor nerve terminals.
p.73
Selective Permeability and Membrane Function
Would osmosis be affected if ATP production stopped?
No, osmosis is a passive process and does not require ATP.
p.11
Composition of the Plasma Membrane
What are the characteristics of the heads of phospholipids?
They are hydrophilic (water-loving) and polar.
p.64
Selective Permeability and Membrane Function
What types of molecules typically use facilitated diffusion?
Polar molecules and ions that cannot easily cross the lipid bilayer.
p.31
Mechanisms of Carrier-Mediated Transport
What role do proteins play in membrane transport?
They act as channels and carriers to facilitate the movement of substances across the membrane.
p.48
Structure of the Cell Membrane
What is the role of integral membrane proteins in relation to membrane fluidity?
They do not significantly increase membrane fluidity.
p.33
Types of Membrane Transport: Active vs Passive
What is facilitated diffusion?
Diffusion that occurs with the help of a carrier protein.
p.41
Types of Membrane Transport: Active vs Passive
What is the main difference between active and passive transport?
Active transport requires ATP hydrolysis, while passive transport does not.
p.1
Types of Membrane Transport: Active vs Passive
What is passive transport?
The movement of substances along their concentration gradient without the use of energy.
p.14
Composition of the Plasma Membrane
What role do phospholipids play in cellular signaling?
They provide some substrate for cellular signaling.
p.30
Types of Membrane Transport: Active vs Passive
What do channel proteins allow to move across the membrane?
Free movement of water as well as selected ions or molecules.
p.13
Glycocalyx and Cell Recognition
How does the glycocalyx contribute to signal reception?
It helps in the reception of signal molecules.
p.74
Selective Permeability and Membrane Function
What happens to the rate of diffusion when the concentration of the particle decreases?
The rate of diffusion decreases.
p.13
Glycocalyx and Cell Recognition
What is the significance of the cellular 'fingerprint'?
It provides each individual with a unique identification.
p.4
Role of Ion Channels: Voltage-Gated vs Ligand-Gated
How are voltage-gated channels opened?
By changes in membrane potential.
p.55
Mechanisms of Carrier-Mediated Transport
What is an example of secondary active transport?
The sodium-glucose cotransporter, which uses the sodium gradient to transport glucose into cells.
p.11
Composition of the Plasma Membrane
Where do the hydrophobic tails of phospholipids extend?
To the interior of the membrane.
p.48
Structure of the Cell Membrane
What is the role of peripheral membrane proteins in relation to membrane fluidity?
They do not significantly affect membrane fluidity.
p.11
Composition of the Plasma Membrane
Are related steroids found in plants?
Yes, related steroids are found in plants.
p.1
Types of Membrane Transport: Active vs Passive
What are the two main types of membrane transport?
Active transport and passive transport.
p.42
Types of Membrane Transport: Active vs Passive
What is the difference between primary and secondary active transport?
Primary active transport directly uses ATP, while secondary active transport uses the energy from the electrochemical gradient created by primary transport.
p.14
Structure of the Cell Membrane
In what way can cholesterol move within the membrane?
It can move in any dimension through the membrane.
p.23
Glycocalyx and Cell Recognition
Where are cell recognition proteins typically found?
On the surface of cell membranes.
p.68
Impact of ATP on Membrane Transport Processes
What is the effect of 2,4 dinitrophenol on intestinal epithelial cells?
It results in loss of ATP synthesis.
p.25
Glycocalyx and Cell Recognition
What is one function of the glycocalyx related to surface charge?
It provides a negative surface charge that repels other negative objects.
p.4
Selective Permeability and Membrane Function
How are molecules assembled to form a selectively permeable barrier in the plasma membrane?
Phospholipids arrange themselves in a bilayer with hydrophilic heads facing outward and hydrophobic tails inward, creating a barrier.
p.64
Types of Membrane Transport: Active vs Passive
Does facilitated diffusion require energy?
No, it is a passive transport process.
p.11
Composition of the Plasma Membrane
Where do the hydrophilic heads of phospholipids lie?
On the outward-facing and inward-facing surfaces of the membrane.
p.68
Selective Permeability and Membrane Function
What is the consequence of the loss of the Na+ gradient in intestinal epithelial cells?
GLUT2 will not be able to transport glucose across the apical membrane.
p.64
Mechanisms of Carrier-Mediated Transport
What role do carrier proteins play in facilitated diffusion?
They help transport specific substances across the cell membrane.
p.25
Glycocalyx and Cell Recognition
How do carbohydrate moieties of glycocalyx participate in immune responses?
Some carbohydrate moieties enter into immune reactions.
p.61
Mechanisms of Carrier-Mediated Transport
What type of specificity do glucose carriers have?
They are stereo-selective for d-glucose.
p.70
Mechanisms of Carrier-Mediated Transport
What is the driving force for ion transport across the membrane?
The sum of the electrical and chemical gradients, known as the gradient of electrochemical potential.
p.42
Types of Membrane Transport: Active vs Passive
Can you name a type of passive transport?
Diffusion or facilitated diffusion.
p.41
Mechanisms of Carrier-Mediated Transport
What is secondary active transport?
Transport that couples the movement of two or more solutes together, using the energy from one solute's electrochemical gradient to drive the transport of another.
p.26
Selective Permeability and Membrane Function
Why is the maintenance of solutes on both sides of the membrane critical to the cell?
It helps to keep the cell from rupturing.
p.51
Types of Membrane Transport: Active vs Passive
What type of transport is always considered uphill?
Primary active transport.
p.30
Mechanisms of Carrier-Mediated Transport
What happens during the conformational change in a carrier protein?
It moves the substances through the interstices of the protein to the other side of the membrane.
p.68
Mechanisms of Carrier-Mediated Transport
What happens to the SGLT on the apical membrane when ATP synthesis is lost?
It will not be able to transport Na+ out of the cell.
p.73
Impact of ATP on Membrane Transport Processes
Which transport processes would cease if ATP production stopped?
The movement of Na+ and K+ out of a cell would cease.
p.11
Composition of the Plasma Membrane
What are the characteristics of the tails of phospholipids?
They are hydrophobic (water-fearing) and nonpolar.
p.33
Types of Membrane Transport: Active vs Passive
What are the two types of diffusion?
Simple diffusion and facilitated diffusion.
p.70
Selective Permeability and Membrane Function
What drives water movement across the plasma membrane?
Differences in osmotic pressure.
p.1
Composition of the Plasma Membrane
What role do proteins play in the cell membrane?
They assist in transport, communication, and structural support.
p.42
Types of Membrane Transport: Active vs Passive
What is passive transport?
The movement of substances across a membrane without the use of energy, following their concentration gradient.
p.41
Mechanisms of Carrier-Mediated Transport
What is primary active transport?
Transport that occurs via membrane proteins directly coupling ATP hydrolysis to solute movement.
p.14
Structure of the Cell Membrane
What is the arrangement of individual phospholipids in the membrane?
They remain in a single monolayer.
p.30
Mechanisms of Carrier-Mediated Transport
How do carrier proteins transport substances?
By binding with molecules or ions and undergoing conformational changes.
p.4
Composition of the Plasma Membrane
What types of molecules constitute the plasma membrane?
Phospholipids, proteins, cholesterol, and carbohydrates.
p.46
Mechanisms of Carrier-Mediated Transport
How do autoantibodies affect Ca²⁺ channels in Lambert-Eaton syndrome?
They bind to and block the channels, inhibiting Ca²⁺-dependent exocytosis.
p.54
Types of Membrane Transport: Active vs Passive
How many molecules are transported in secondary active transport?
Two or more molecules through a carrier protein.
p.25
Glycocalyx and Cell Recognition
What role does glycocalyx play in hormone binding?
It acts as a receptor for binding hormones, such as insulin, activating attached internal proteins.
p.33
Types of Membrane Transport: Active vs Passive
What is diffusion?
Random molecular movement of substances molecule by molecule through intermolecular spaces in the membrane or with the help of proteins.
p.4
Role of Ion Channels: Voltage-Gated vs Ligand-Gated
How are ligand-gated channels opened?
By the binding of specific molecules (ligands) to the channel.
p.61
Mechanisms of Carrier-Mediated Transport
What protein mediates glucose transport across adipose cell membranes?
GLUT4 (the insulin-dependent glucose transporter).
p.59
Selective Permeability and Membrane Function
What is the relationship between lactose intolerance and amino acid levels?
Amino acid levels decrease in lactose intolerance.
p.1
Types of Membrane Transport: Active vs Passive
What is active transport?
The movement of substances against their concentration gradient, requiring energy.
p.1
Structure of the Cell Membrane
What is the significance of the fluid mosaic model?
It describes the dynamic nature of the cell membrane, where lipids and proteins can move laterally.
p.74
Selective Permeability and Membrane Function
How does the size of the particle affect its diffusion rate?
Increasing the size of the particle decreases the rate of diffusion.
p.68
Selective Permeability and Membrane Function
Why is glucose transport from the apical to basolateral side of intestinal cells reduced after treatment with 2,4 dinitrophenol?
Because the Na+ gradient across the apical membrane will be dissipated.
p.23
Glycocalyx and Cell Recognition
What can happen if cell recognition proteins malfunction?
It can lead to autoimmune diseases or tissue rejection.
p.31
Selective Permeability and Membrane Function
What is the primary function of proteins in the body?
To perform a variety of functions including structural support, transport, and catalysis.
p.4
Selective Permeability and Membrane Function
How does the plasma membrane maintain an internal environment that differs from extracellular fluid?
By regulating the transport of ions and molecules through selective permeability.
p.70
Selective Permeability and Membrane Function
What are aquaporins?
Channel proteins that allow rapid water movement across the plasma membrane.
p.64
Types of Membrane Transport: Active vs Passive
What is the difference between facilitated diffusion and simple diffusion?
Facilitated diffusion requires specific transport proteins, while simple diffusion does not.
p.59
Selective Permeability and Membrane Function
What happens to amino acid levels in lactose intolerance?
Amino acid levels decrease.
p.61
Mechanisms of Carrier-Mediated Transport
Where does primary active transport of glucose occur?
In the gut, but not in adipose tissue.
p.42
Mechanisms of Carrier-Mediated Transport
What is the role of carrier proteins in membrane transport?
They assist in the movement of substances across the membrane, either actively or passively.
p.41
Types of Membrane Transport: Active vs Passive
What characterizes passive transport?
It does not require ATP hydrolysis or coupling to another solute.
