Podcast
Questions and Answers
What is the primary function of phagocytosis in cellular processes?
What is the primary function of phagocytosis in cellular processes?
- Facilitating fluid intake into the cell
- Transporting sodium and potassium ions
- Bringing solid particles into the cell (correct)
- Excreting waste products from the cell
Which process requires energy (ATP) for the transport of substances across the cell membrane?
Which process requires energy (ATP) for the transport of substances across the cell membrane?
- Facilitated diffusion
- Simple diffusion
- Active transport (correct)
- Osmosis
What distinguishes exocytosis from endocytosis?
What distinguishes exocytosis from endocytosis?
- Endocytosis uses energy while exocytosis does not
- Exocytosis releases materials from the cell (correct)
- Exocytosis involves the intake of fluids
- Endocytosis is a passive process
What is the main difference between phagocytosis and pinocytosis?
What is the main difference between phagocytosis and pinocytosis?
Which component is often involved in active transport mechanisms?
Which component is often involved in active transport mechanisms?
What is the primary driver of diffusion?
What is the primary driver of diffusion?
Which statement about facilitated diffusion is true?
Which statement about facilitated diffusion is true?
What condition is described when the concentration of molecules is uniform throughout a solution?
What condition is described when the concentration of molecules is uniform throughout a solution?
In osmosis, water moves toward which type of solution?
In osmosis, water moves toward which type of solution?
What separates the two solutions in osmosis?
What separates the two solutions in osmosis?
What role do protein channels play in facilitated diffusion?
What role do protein channels play in facilitated diffusion?
Which process does NOT require energy?
Which process does NOT require energy?
What is osmotic pressure primarily caused by?
What is osmotic pressure primarily caused by?
What characterizes a concentrated solution?
What characterizes a concentrated solution?
What happens to a red blood cell (RBC) placed in a hypertonic solution?
What happens to a red blood cell (RBC) placed in a hypertonic solution?
Which statement correctly describes osmotic pressure?
Which statement correctly describes osmotic pressure?
In which environment is a plant cell considered turgid?
In which environment is a plant cell considered turgid?
What movement occurs when a dilute solution is introduced to a cell in a concentrated solution?
What movement occurs when a dilute solution is introduced to a cell in a concentrated solution?
What is the result of osmotic pressure acting on the side of a membrane with a higher solute concentration?
What is the result of osmotic pressure acting on the side of a membrane with a higher solute concentration?
Which of the following best describes the effect of osmosis in living organisms?
Which of the following best describes the effect of osmosis in living organisms?
What occurs when the membrane of a cell does not permit the passage of a solute?
What occurs when the membrane of a cell does not permit the passage of a solute?
Which type of molecule can pass through the plasma membrane without any assistance?
Which type of molecule can pass through the plasma membrane without any assistance?
What is the primary factor that affects the rate of diffusion?
What is the primary factor that affects the rate of diffusion?
Which statement best describes osmosis?
Which statement best describes osmosis?
What characterizes a semi-permeable membrane?
What characterizes a semi-permeable membrane?
Which statement about macromolecule transport is true?
Which statement about macromolecule transport is true?
Which transport mechanism requires the use of energy?
Which transport mechanism requires the use of energy?
What role does temperature play in the rate of diffusion?
What role does temperature play in the rate of diffusion?
What causes the movement of oxygen from alveoli to blood in lung capillaries?
What causes the movement of oxygen from alveoli to blood in lung capillaries?
How does the size of a molecule affect its ability to diffuse across the plasma membrane?
How does the size of a molecule affect its ability to diffuse across the plasma membrane?
Which processes are classified as passive transport mechanisms?
Which processes are classified as passive transport mechanisms?
What defines active transport mechanisms?
What defines active transport mechanisms?
What does Brownian motion refer to in the context of diffusion?
What does Brownian motion refer to in the context of diffusion?
What is the primary difference between exocytosis and endocytosis?
What is the primary difference between exocytosis and endocytosis?
Why do ions and charged molecules have difficulty crossing the plasma membrane?
Why do ions and charged molecules have difficulty crossing the plasma membrane?
In a solution, which component is typically considered the solute?
In a solution, which component is typically considered the solute?
What concentration gradient do molecules move along during diffusion?
What concentration gradient do molecules move along during diffusion?
Flashcards are hidden until you start studying
Study Notes
Plasma Membrane Permeability
- Plasma membrane is differentially permeable, allowing some molecules to pass while restricting others.
- Lipid-soluble molecules like alcohol diffuse easily due to the lipid structure of the membrane.
- Gases, such as oxygen, diffuse through the lipid bilayer, influenced by their concentration gradient.
Types of Transport Mechanisms
- Passive mechanisms (require no ATP) include:
- Simple diffusion: Molecules move from areas of higher to lower concentration.
- Facilitated diffusion: Requires specific protein channels to aid movement of larger molecules like glucose, also occurs down a concentration gradient.
- Osmosis: Diffusion of water across a selectively permeable membrane, moving from areas of low solute concentration to high.
- Active mechanisms (require ATP) include:
- Exocytosis: Process of expelling materials from a cell.
- Endocytosis: Process of engulfing materials into a cell; includes phagocytosis (cell eating) and pinocytosis (cell drinking).
Factors Influencing Diffusion
- Temperature: Higher temperatures increase the rate of diffusion.
- Concentration gradient: Greater concentration differences accelerate diffusion.
- Size of molecules: Larger molecules diffuse more slowly.
Osmosis and Osmotic Pressure
- Osmosis is the spontaneous movement of water towards areas of higher solute concentration, resulting in osmotic pressure on the membrane.
- An example is a thistle tube demonstrating water movement from a dilute solution to a concentrated one.
- Osmotic pressure can cause cells to shrink (crenation) or swell (turgidity), depending on their environment.
Water Balance in Cells
- Plant cells maintain water balance through turgidity; they thrive in hypotonic environments.
- Osmosis continuously occurs in living systems; for instance, in the large intestine, water is absorbed effectively.
Endocytosis and Exocytosis
- Endocytosis surrounds particles or fluids with a membrane to bring them into the cell.
- Exocytosis releases materials from the cell, often involving materials vacuoles merging with the membrane.
- Active transport, such as the sodium-potassium pump, is energy-dependent and distinct from facilitated diffusion, which is passive.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
