Biology Chapter: Cell Transport Mechanisms

Questions and Answers

What is the concentration gradient?

The difference in concentration of a substance from one area to another.

What is diffusion?

Diffusion is the movement of molecules from a region of high concentration to a region of low concentration.

Does diffusion require energy?

False

What is passive transport?

Passive transport is the movement of molecules across a cell membrane without using energy. Signup and view all the answers

Equilibrium is...

The concentration of molecules is the same throughout a solution. Signup and view all the answers

What kind of molecules can diffuse across a cell membrane?

Small non-polar molecules (like oxygen and carbon dioxide) and water. Signup and view all the answers

What is osmosis?

Movement of water molecules across a membrane from a region of higher water concentration to region of lower water concentration. Signup and view all the answers

Does osmosis require energy?

False Signup and view all the answers

Facilitated diffusion is...

The diffusion of molecules across a cell membrane through transport proteins. Signup and view all the answers

What do carrier proteins transport?

Carrier proteins move ions (like Na+). Signup and view all the answers

What do channel proteins transport?

Channel proteins move sugars and amino acids. Signup and view all the answers

What is a hypotonic solution?

Hypotonic solutions have less solute concentration than the cell. Signup and view all the answers

What is an isotonic solution?

Isotonic solutions have equal concentrations of solute as the cell. Signup and view all the answers

What are hypertonic solutions?

Hypertonic solutions have higher solute concentrations than the cell. Signup and view all the answers

What is active transport?

Active transport is the movement of molecules across a cell membrane from a region of low concentration to a region of high concentration with the use of energy. Signup and view all the answers

What can you look for in active transport?

The use of energy (ATP), movement from low concentration to high concentration, and transport proteins. Signup and view all the answers

What are the two types of active transport?

Na-K Pump and Proton (H+) Pump. Signup and view all the answers

What is endocytosis?

Endocytosis is the process of bringing large molecules into a cell in a vesicle. Signup and view all the answers

What is pinocytosis?

The process of bringing liquids into a cell in a vesicle, an active transport. Signup and view all the answers

What is phagocytosis?

The process of bringing large particles into a cell by engulfing them in a membrane. Signup and view all the answers

What is exocytosis?

The process of releasing molecules from a cell in a vesicle. Signup and view all the answers

What are the two types of exocytosis?

Secretion and excretion. Signup and view all the answers

What is secretion?

Secretion is the release of cell products (useful). Signup and view all the answers

What is excretion?

Excretion is the dumping of waste materials. Signup and view all the answers

Study Notes

Concentration Gradient

Represents the difference in the concentration of a substance between two areas.

Diffusion

Involves the movement of molecules from high concentration to low concentration.
Does not require energy.

Passive Transport

Movement of molecules across cell membranes without energy expenditure.
Achieves equilibrium, where the concentration of molecules is uniform throughout the solution.

Molecules that Diffuse

Small non-polar molecules (e.g., oxygen, carbon dioxide) can easily cross cell membranes.
Water molecules can also diffuse through membranes.

Osmosis

Specific type of passive transport involving the movement of water from an area of higher water concentration to lower.
Does not require energy.

Facilitated Diffusion

Process of molecules crossing cell membranes via transport proteins.
Carrier proteins transport ions (e.g., sodium ions).
Channel proteins transport sugars and amino acids.

Solution Types

Hypotonic Solution: Lower solute concentration than the cell; can lead to cell swelling.
Isotonic Solution: Equal solute concentration compared to the cell, maintaining cell stability.
Hypertonic Solution: Higher solute concentration than the cell; can cause cell shrinkage.

Active Transport

Moves molecules from low concentration to high concentration using energy (ATP).
Requires transport proteins for the process.

Types of Active Transport

Na-K Pump: Transports sodium and potassium ions in neurons to facilitate nerve signal transmission.
Proton (H+) Pump: Involves movement of hydrogen ions in chloroplasts and mitochondria for ATP production.

Endocytosis

Mechanism to bring large molecules into a cell via vesicles.

Pinocytosis

A form of endocytosis that specifically involves the intake of liquids.
Active transport process.

Phagocytosis

Engulfs large particles through membrane wrapping to incorporate them into the cell.

Exocytosis

The process of releasing contents from a cell through vesicles.

Types of Exocytosis

Secretion: Release of useful cell products.
Excretion: Elimination of waste materials from the cell.

Studying That Suits You

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

Description

Test your understanding of cell transport processes including diffusion, osmosis, and facilitated diffusion. This quiz covers the key concepts related to concentration gradients and passive transport. Perfect for students studying biology or life sciences.