Bio I -Unit 2 Test - Unit 2 Homeostasis and Feedback (2.4-2.6)

Front

What is passive transport?

Back

Passive transport is the movement of molecules across a cell membrane without the use of energy, moving down their concentration gradient from high concentration to low concentration.

Front

What is active transport?

Back

Active transport is the movement of molecules across a cell membrane against their concentration gradient, requiring energy (ATP), such as in the Sodium-Potassium Pump.

Front

What happens to a cell in a hypertonic solution?

Back

In a hypertonic solution, the concentration of solute outside the cell is higher than inside, causing water to move out of the cell, leading to cell shriveling.

Front

Define hypertonic solution.

Back

A hypertonic solution has a higher concentration of solute and a lower concentration of water compared to the inside of a cell.

Front

What is homeostasis?

Back

Homeostasis is the process by which a cell or organism maintains a stable internal environment despite changes in external conditions.

Front

What role do cell membranes play in homeostasis?

Back

Cell membranes control the movement of substances in and out of the cell, which is essential for maintaining homeostasis.

Front

What is the Sodium-Potassium Pump?

Back

The Sodium-Potassium Pump is an active transport mechanism that moves sodium ions out of the cell and potassium ions into the cell against their concentration gradients, using ATP.

Front

What occurs to a cell placed in freshwater?

Back

A cell placed in freshwater (hypotonic solution) will swell as water moves into the cell, potentially causing it to burst.

Front

Define isotonic solution.

Back

An isotonic solution has an equal concentration of solute and water inside and outside the cell, resulting in no net movement of water.

Front

What is the effect of a hypotonic solution on a cell?

Back

In a hypotonic solution, the concentration of solute is lower outside the cell, causing water to move into the cell, which may lead to swelling or bursting.