MPharm Programme - Cell Science - Cellular Processes
42 Questions
0 Views

Choose a study mode

Play Quiz
Study Flashcards
Spaced Repetition
Chat to Lesson

Podcast

Play an AI-generated podcast conversation about this lesson

Questions and Answers

What effect does a larger mass of the diffusing substance have on its rate of diffusion?

  • It increases the rate of diffusion.
  • It decreases the rate of diffusion. (correct)
  • It causes diffusion to stop completely.
  • It has no effect on the diffusion rate.

What is required for facilitated diffusion to occur?

  • Active transport mechanisms.
  • Energy in the form of ATP.
  • An increase in temperature.
  • A carrier protein in the membrane. (correct)

Which of the following factors decreases the rate of diffusion?

  • Shorter diffusion distance.
  • Decreased concentration gradient. (correct)
  • Increased surface area.
  • Higher temperature.

In simple diffusion, particles move in which direction?

<p>To equalize the concentration gradient. (D)</p> Signup and view all the answers

What is the role of ion channels in facilitated diffusion?

<p>To allow passage of small, inorganic ions that cannot diffuse directly. (D)</p> Signup and view all the answers

What is the term for the charge difference across the plasma membrane?

<p>Membrane potential (C)</p> Signup and view all the answers

Which type of transport requires energy from the cell?

<p>Active transport (C)</p> Signup and view all the answers

What is the primary factor driving the process of diffusion?

<p>Kinetic energy of particles (D)</p> Signup and view all the answers

What is a characteristic feature of receptor-mediated endocytosis?

<p>It requires specific receptors on the cell surface (A)</p> Signup and view all the answers

Which type of passive transport specifically involves the movement of water?

<p>Osmosis (A)</p> Signup and view all the answers

What is the primary solvent in biological solutions?

<p>Water (B)</p> Signup and view all the answers

Which fluid is classified as part of the extracellular fluid (ECF)?

<p>Plasma (A)</p> Signup and view all the answers

How is selective permeability significant to cells?

<p>It maintains different concentrations on either side of the plasma membrane. (B)</p> Signup and view all the answers

What does a concentration gradient indicate?

<p>Difference in concentration between two areas of solution. (B)</p> Signup and view all the answers

Which of the following is NOT a type of transport process across cell membranes?

<p>Ion Oscillation (D)</p> Signup and view all the answers

What role does the cerebrospinal fluid play in the body?

<p>It serves as a cushioning and protective layer for the brain and spinal cord. (B)</p> Signup and view all the answers

In which of the following are solutes dissolved?

<p>Solvent (D)</p> Signup and view all the answers

Which of the following best describes an electrical gradient?

<p>The difference in electrical charges between two regions. (C)</p> Signup and view all the answers

What is released by nerve cells during the process of exocytosis?

<p>Neurotransmitters (A)</p> Signup and view all the answers

Which of the following is a requirement for exocytosis to occur?

<p>Calcium ions (Ca2+) (D)</p> Signup and view all the answers

In which process do vesicles move substances across a cell before releasing them?

<p>Transcytosis (B)</p> Signup and view all the answers

Which of the following substances is typically released from the β-cells of the pancreas?

<p>Insulin (A)</p> Signup and view all the answers

What happens at the synaptic terminal of nerve cells?

<p>Exocytosis of neurotransmitters (B)</p> Signup and view all the answers

What is the main role of exocytic vesicles during exocytosis?

<p>Merging with the plasma membrane and releasing contents (B)</p> Signup and view all the answers

Which type of cells are closely involved in transcytosis during pregnancy?

<p>Endothelial cells (B)</p> Signup and view all the answers

What is the primary energy source required for exocytosis?

<p>ATP (B)</p> Signup and view all the answers

What type of protein channel opens and closes in response to changes in membrane potential?

<p>Voltage gated channel (A)</p> Signup and view all the answers

What is true about carrier mediated facilitated diffusion?

<p>It involves saturation when the transport maximum is reached. (D)</p> Signup and view all the answers

Which of the following substances is NOT typically moved using carrier mediated facilitated diffusion?

<p>Calcium ions (A)</p> Signup and view all the answers

How do water molecules primarily pass through the plasma membrane during osmosis?

<p>By moving through aquaporins or the lipid bilayer (C)</p> Signup and view all the answers

What defines a gated ion channel?

<p>It opens and closes in response to specific triggers. (D)</p> Signup and view all the answers

Which of the following describes the process of facilitated diffusion?

<p>It is a selective process involving specific transporter proteins. (B)</p> Signup and view all the answers

What type of gated channel responds to the binding of a specific molecule?

<p>Ligand gated channel (C)</p> Signup and view all the answers

Which statement about osmosis is correct?

<p>Osmosis is the diffusion of water through a selectively permeable membrane. (D)</p> Signup and view all the answers

What occurs after the phosphorylation of the pump protein by ATP?

<p>The protein changes shape, expelling Na+ outside (D)</p> Signup and view all the answers

What distinguishes secondary active transport from primary active transport?

<p>Use of an electrochemical gradient as its energy source (A)</p> Signup and view all the answers

Which type of endocytosis involves a specific receptor protein recognizing and binding to a particle?

<p>Receptor-mediated endocytosis (D)</p> Signup and view all the answers

What triggers the release of K+ from the pump protein?

<p>Extracellular K+ binding (B)</p> Signup and view all the answers

What is the primary function of exocytosis?

<p>Movement of macromolecules out of the cell (B)</p> Signup and view all the answers

What is one characteristic of phagocytosis?

<p>It requires energy in the form of ATP (C)</p> Signup and view all the answers

Which statement is true about co-transporters (symporters)?

<p>They move two different substances in the same direction (B)</p> Signup and view all the answers

Which of the following processes is NOT a type of endocytosis?

<p>Exocytosis (B)</p> Signup and view all the answers

Flashcards

Membrane transport

The movement of substances across cell membranes, which can be passive, active, or through vesicles.

Passive transport

The movement of substances across cell membranes without requiring cellular energy.

Active transport

The movement of substances across cell membranes against their concentration gradient, requiring cellular energy.

Vesicular transport

The transport of substances across cell membranes within membrane-bound sacs.

Signup and view all the flashcards

Concentration gradient

The difference in concentration of a substance between two areas.

Signup and view all the flashcards

Selective permeability

The ability of a cell membrane to allow some substances to pass through while blocking others.

Signup and view all the flashcards

Intracellular fluid (ICF)

The fluid inside cells, making up 2/3 of the body's total fluid.

Signup and view all the flashcards

Extracellular fluid (ECF)

The fluid outside cells, consisting of interstitial fluid, plasma, lymph, and cerebrospinal fluid.

Signup and view all the flashcards

Membrane potential

The difference in electrical charge across a cell membrane. It is important for moving substances across the membrane.

Signup and view all the flashcards

Electrochemical gradient

A combination of the concentration gradient and the electrical gradient that affects the movement of a specific ion across a cell membrane.

Signup and view all the flashcards

Diffusion

The random movement of particles from an area of high concentration to an area of low concentration.

Signup and view all the flashcards

Simple Diffusion

The movement of substances across a cell membrane from an area of higher concentration to an area of lower concentration, without requiring cellular energy.

Signup and view all the flashcards

Facilitated Diffusion

The substances move across a cell membrane through a channel, requiring a carrier protein in the cell membrane, but not ATP. The movement is still from an area of higher concentration to an area of lower concentration.

Signup and view all the flashcards

Ion Channels

Integral transmembrane proteins that allow passage of small, inorganic ions across a membrane.

Signup and view all the flashcards

Protein Transporters

A type of facilitated diffusion using carrier proteins. The substance binds to the carrier protein, which changes shape to allow the substance to pass across the membrane.

Signup and view all the flashcards

Ligand-Gated Channel

A type of ion channel where a specific molecule binds to the channel, causing it to open or close.

Signup and view all the flashcards

Voltage-Gated Channel

A type of ion channel that opens or closes in response to changes in the electrical charge across the cell membrane.

Signup and view all the flashcards

Mechanically-Gated Channel

A type of ion channel that opens or closes in response to mechanical stress or pressure.

Signup and view all the flashcards

Carrier-Mediated Facilitated Diffusion

A type of passive transport that uses carrier proteins to move molecules down their concentration gradient across the cell membrane.

Signup and view all the flashcards

Transport Maximum

The maximum rate at which a carrier protein can transport a substance. Once all the carrier proteins are occupied, the transport rate plateaus.

Signup and view all the flashcards

Osmosis

The movement of water molecules across a semi-permeable membrane from an area of high water concentration to an area of low water concentration. It is a form of passive transport.

Signup and view all the flashcards

Aquaporins

Integral membrane proteins that function as water channels, allowing water molecules to pass through the cell membrane more easily.

Signup and view all the flashcards

Primary active transport

A type of active transport that uses energy directly from ATP hydrolysis to move substances across a membrane against their concentration gradient.

Signup and view all the flashcards

Pump protein

A protein embedded in the cell membrane that uses energy from ATP to move ions or molecules against their concentration gradient.

Signup and view all the flashcards

Endocytosis

The process by which a cell membrane engulfs extracellular material and brings it inside the cell.

Signup and view all the flashcards

Exocytosis

The process by which a cell membrane releases material from inside the cell into the extracellular space.

Signup and view all the flashcards

Receptor-mediated endocytosis

A type of endocytosis where specific molecules bind to receptors on the cell membrane, triggering the formation of a vesicle.

Signup and view all the flashcards

Pinocytosis

A type of endocytosis where the cell membrane engulfs small amounts of extracellular fluid, forming a vesicle.

Signup and view all the flashcards

Phagocytosis

A type of endocytosis where the cell engulfs large particles, such as bacteria or debris, forming a phagosome.

Signup and view all the flashcards

Secondary active transport

A type of active transport that uses the energy stored in an electrochemical gradient to move other substances across the membrane.

Signup and view all the flashcards

Neurotransmission

A type of exocytosis that is specifically used by nerve cells to communicate with other cells by releasing chemicals called neurotransmitters.

Signup and view all the flashcards

Exocytosis in Presynaptic Neuron

A type of exocytosis that occurs at the synaptic terminal of a neuron, where neurotransmitters are released from vesicles into the synaptic cleft.

Signup and view all the flashcards

Transcytosis

The process by which a substance is moved through a cell from one side to the other, entering through endocytosis on one side and exiting through exocytosis on the other.

Signup and view all the flashcards

Study Notes

MPharm Programme - Cell Science - Cellular Process 1 & 2

  • The lecture covers different transport processes across cell membranes
  • Passive processes include simple diffusion, facilitated diffusion, and osmosis
  • Active processes involve the use of energy to move molecules against concentration gradients
  • Active processes include primary (direct ATP use) and secondary (using electrochemical gradients) active transport
  • Endocytosis involves the movement of large molecules into the cell
  • Types of endocytosis include phagocytosis, fluid endocytosis (pinocytosis), and receptor-mediated endocytosis
  • Exocytosis involves the movement of large molecules out of the cell
  • The learning objectives include understanding and explaining different transport processes, how substances are transported across membranes, examples of transport processes in cells, and their application to the nervous system and neurotransmission
  • Terminology includes intracellular fluid (ICF), extracellular fluid (ECF), interstitial fluid, plasma, lymph, cerebrospinal fluid, solvent, solute, and concentration gradient
  • Factors influencing diffusion include steepness of concentration gradient, temperature, mass of the substance, surface area, and distance
  • The electrochemical gradient combines concentration gradient and electrical gradient to affect movement of ions across membranes.
  • Simple diffusion depends on lipid solubility
  • Facilitated diffusion involves a carrier protein but not ATP and moves solute down its concentration gradient
  • Ion channels can be ligand or voltage gated.
  • Facilitated diffusion involves channel-mediated and carrier-mediated processes.
  • Example of substances transported through facilitated diffusion through carriers include glucose, fructose, and galactose.
  • Osmosis is a special form of diffusion, specifically the diffusion of water through a semi-permeable membrane. Water passes through the lipid bilayer by simple diffusion, or through proteins called aquaporins.
  • Osmolarity is the total solute concentration of a solution
  • Tonicity refers to the ability of a solution to change the shape or tone of cells by altering their internal water volume
  • Various solutions, like isotonic, hypertonic, and hypotonic solutions, can cause different effects on cells, either shrinking, swelling, or retaining their normal size and shape due to osmosis.
  • Active transport uses ATP (or an electrochemical gradient) to move molecules against a concentration gradient.
  • Primary active transport uses ATP directly, while secondary active transport uses electrochemical gradients. Sodium-potassium "pumps," Calcium pumps, and Hydrogen pumps are examples.
  • Secondary active transport, symporters and antiporters, move molecules along with another molecule (a substance down its concentration gradient coupled with transport of the other molecule)
  • Vesicular transport involves endocytosis and exocytosis, respectively.
  • Endocytosis involves phagocytosis, pinocytosis and receptor-mediated endocytosis
  • Exocytosis involves release of substances through vesicles fusing with the plasma membrane, and can be important for adding new membrane components, releasing neurotransmitters, or secreting hormones
  • Transcytosis moves substances across cell layers, often relevant to blood vessels lining
  • Key textbook readings are recommended for in-depth knowledge.

Studying That Suits You

Use AI to generate personalized quizzes and flashcards to suit your learning preferences.

Quiz Team

Related Documents

PHA115 Lecture Cellular Process Student Handout PDF

Description

This quiz focuses on cellular transport processes as covered in the MPharm program. It explores passive processes like diffusion and osmosis, as well as active transport mechanisms such as endocytosis and exocytosis. Understanding these concepts is essential for applications in the nervous system and neurotransmission.

More Like This

Use Quizgecko on...
Browser
Open
Browser
Browser