Biology Unit 1.2

Front

What is a response to stimulus?

Back

A response to stimulus is a reaction of an organism to changes in its environment, such as sweating or panting in dogs to regulate body temperature.

Front

Define hypotonic solution.

Back

A hypotonic solution is one where the concentration of solutes is lower outside the cell than inside, causing water to move into the cell.

Front

What happens to red blood cells in a hypertonic solution?

Back

Red blood cells will lose water and decrease in size when placed in a hypertonic solution.

Front

What is dynamic equilibrium?

Back

Dynamic equilibrium refers to a state of balance in biological systems where conditions remain stable despite ongoing processes.

Front

What is homeostasis?

Back

Homeostasis is the ability of an organism to maintain a stable internal environment despite changes in external conditions.

Front

What is the significance of temperature regulation in bumblebees?

Back

Bumblebees regulate their body temperature through behaviors like shivering, allowing them to maintain a temperature above the surrounding air.

Front

What is the difference between diffusion and osmosis?

Back

Diffusion is the movement of particles from an area of high concentration to low concentration, while osmosis specifically refers to the movement of water across a semipermeable membrane.

Front

What is the role of cell membranes in osmosis?

Back

Cell membranes are semipermeable, allowing water to pass through while restricting the movement of solutes, which is crucial for maintaining cell turgor.

Front

Define isotonic solution.

Back

An isotonic solution has equal concentrations of solutes inside and outside the cell, resulting in no net movement of water.

Front

What is the effect of a hypertonic solution on plant cells?

Back

Plant cells placed in a hypertonic solution will lose water, leading to plasmolysis, where the cell membrane pulls away from the cell wall.