Turgor PressureTurgor Pressure

Turgor Pressure-Turgor Pressure-

The pressure exerted by water inside the cell against the cell wall.

Plant CellPlant Cell

How does turgor How does turgor pressure affect plants?pressure affect plants?

The central vacuole fills with water getting The central vacuole fills with water getting bigger and bigger.bigger and bigger.

This pushed the organelles and cytoplasm into This pushed the organelles and cytoplasm into the cell wall.the cell wall.

The cell wall then becomes very rigid as a The cell wall then becomes very rigid as a result of the turgor pressure.result of the turgor pressure.

This rigidity allows a plant to stand up.This rigidity allows a plant to stand up. Without turgor pressure plants would always Without turgor pressure plants would always

look wilted and would never stand up straight.look wilted and would never stand up straight.

TropismTropismTropism is a Tropism is a response of a plant to response of a plant to a environmental a environmental stimulus. stimulus.

TropismTropism Types of tropism:Types of tropism:

PhototropismPhototropism HydrotropismHydrotropism GeotropismGeotropism

PhototropismPhototropism A tendency of plants to grow towards a A tendency of plants to grow towards a

source of lightsource of light

http://plantsinmotion.bio.indiana.edu/http://plantsinmotion.bio.indiana.edu/plantmotion/movements/tropism/plantmotion/movements/tropism/tropisms.htmltropisms.html

PhototropismPhototropismhttp://www.5min.com/Video/Plant-http://www.5min.com/Video/Plant-

Physiology-Phototropic-Response-Physiology-Phototropic-Response-13543411354341

HydrotropismHydrotropism The positive or negative movement of The positive or negative movement of

growth as a plant root moves toward, or growth as a plant root moves toward, or away from moisture.away from moisture.

GeotropismGeotropism Any positive (or negative) movement or Any positive (or negative) movement or

growth of a plant or sessile animal in growth of a plant or sessile animal in response to (or against) the force of response to (or against) the force of gravity.gravity.

GeotropismGeotropism