Turgor Pressure and Roots!

Discussing our gummy worm lab How did the mass of your gummy worm change? water solution 2g salt solution 8g salt solution Why would this be?!?

Main Understandings Explain osmosis; diffusion, active transport and root pressure in root hairs Explain transpiration in plants, cohesion and adhesion as properties of water, and turgor pressure

What i think is cool about plants!

Remind me Think-Pair-Share Where are sugars produced in our plant? By what process? Transported by what? Where does water leave our plant?

But where does water first enter our plants?! The roots! The roots have tiny little extensions called root hairs that help absorb water and minerals! Water moves into our roots via osmosis The minerals have to be moved into the root cells against their concentration gradient by active transport. Start here

Water then ... Moves up towards the leaves through the xylem! What was the movement of water out of the leaves called again? Transpiration

Why else is water important? Turgor pressure! Water is why are stems are either firm and straight up or wilted! Turgor pressure is when water moves into our plant cell pushing the cell membrane against the cell wall. As a result, the plant is firm or turgid. When water moves out of our plant cell, the cell shrinks and wilts! Hypertonic solution What kind of solution would result in a turgid or wilted plant? Hypotonic solution

Turgor pressure also affects our guard cells When the guard cells are turgid, they open which allows gas exchange When the guard cells are flaccid or wilted, they close and reduce the amount of water loss and gas exchange.

Time lapsed turgor pressure Stop when straightens

Transpiration summary The process by which water leaves the plant. Water enters the plant by the root and root hair cells Then moves up the xylem When it reaches the stomata it turns to water vapour and leaves the plant. The water leaving the plant pulls on the other water molecules by COHESION The adhesion of water to the xylem cells helps prevent water from going back down.

Gas Exchange in plants In sunlight: Photosynthesis Carbon dioxide flows into the plant through the stomata to make sugars. Oxygen leaves through the stomata. When it is dark: Plants use Cellular Respiration They use the sugar they made and oxygen to produce energy.They then release carbon dioxide.

Woody Trees/ stems have another way! Woody trees and stems also have tissues with pores called lenticels! Allows for even more gas exchange to occur.

Questions? We will now be exploring factors that affect the rate of transpiration using an online virtual lab!