Chapter 3: Movement in and out of the cell

Movement of particles across a cell membrane from a region of lower concentration to a region of higher concentration, against a concentration gradient. This process requires energy from respiration and uses carrier proteins.

Proteins embedded in the cell membrane that bind to specific molecules and transport them across the membrane. They are responsible for active transport.

The energy required for active transport is produced through the process of aerobic respiration in the mitochondria.

Higher oxygen concentration increases the rate of aerobic respiration, providing more energy for active transport.

The number of carrier proteins in the cell membrane affects the rate of active transport; more proteins mean faster transport.

The net movement of water molecules from a region of high water potential (dilute solution) to a region of low water potential (concentrated solution) across a partially permeable membrane.

When a plant cell is placed in a solution with a lower water potential (high concentration of solutes), water moves out of the cell, causing the vacuole to shrink and the cell to become flaccid.

When a plant cell is placed in a solution with a higher water potential (lower concentration of solutes), water moves into the cell, causing the vacuole to expand and the cell to become turgid.

The movement of particles from a region of higher concentration to a region of lower concentration due to random motion.

The energy required for diffusion comes from the random movement of molecules and ions.

A plant cell that is swollen with water due to the influx of water via osmosis.

The pressure exerted by the cell contents against the cell wall in a turgid plant cell.

The shrinking of the cytoplasm of a plant cell away from the cell wall when placed in a hypertonic solution.

A plant cell that has lost water and is limp or wilted due to water loss via osmosis.

The intake of ions by root hairs, powered by active transport.

The shrinking of a plant cell's cytoplasm, causing the cell membrane to pull away from the cell wall. This is irreversible and damages the cell.

Plant cells have a rigid cell wall that resists inward pressure. This pressure, caused by the inward movement of water due to osmosis, is called turgor pressure.

When a plant loses water, the internal pressure drops. This causes the cell to become flaccid, meaning it loses its firmness and becomes limp.

Animal cells are different from plant cells. They lack a rigid cell wall, so they are more susceptible to bursting when exposed to higher water potential.

When an animal cell is placed in a solution with higher water potential it gains water and bursts. This is because it lacks a rigid cell wall to resist the pressure.

When an animal cell is placed in a solution with lower water potential, it loses water and shrinks. This is because water moves out of the cell to balance the concentration.

The passive movement of water molecules from a region of high water potential (more water) to a region of low water potential (less water) across a semi-permeable membrane.

Active transport requires energy, while osmosis is a passive process that doesn't need energy. This is because osmosis follows the concentration gradient.

Minerals, unlike water, move against their concentration gradient, meaning they move from regions of lower concentration to higher concentration. This requires energy.

Root hair cells absorb water through osmosis and minerals through active transport. This is because water follows the concentration gradient, while minerals require energy to move against it.

The stiff wall surrounding plant cells. It helps maintain their shape and provides support.

The process where plant cells take in water from their surroundings causing them to swell and become firm. This is vital for plant growth and support.

The difference in water concentration between two solutions, determining the direction of water movement.

The process by which plants absorb water from the soil through their root hairs, driven by the difference in water potential.

The process of preserving food by adding high concentrations of salt or sugar, creating a hypertonic environment that draws water out of microorganisms, inhibiting their growth and preventing spoilage.

The death of plants caused by irrigation with seawater, which has a high salt concentration, leading to water loss from the plant cells due to osmosis.

The process by which plants maintain their shape and rigidity due to the pressure exerted by water inside their cells.