Land Plant Problems

Plants Invade the Land

Plants invade the Land

Green Algae Land Plants

Kingdom Protista Kingdom Plantae

• Photosynthetic Photosynthetic

• Multicellular Multicellular

• Live in water Live on land

Problems Land Plants Need to Solve

1. How to Prevent Dehydration?

Answer = cuticle

waxy covering

Problems Land Plants Need to Solve

2. How to do Gas Exchange?

(CO2 in, O2 out)

Answer: Stomata*

*Also release

excess water

stoma

Guard cell

Guard cell

Stomata Solve another Problem

Open & close to control water loss

OpenClosed

Problems Land Plants Need to Solve

3. How to Get Nutrients from Land?

Answer: Roots

Problems Land Plants Need to Solve

4. How to have Reproduction NOT dependent on water?

a. Make pollen

(plant sperm

that won’t

dry out)

Problems Land Plants Need to Solve

4. How to have Reproduction NOT dependent on water?

b. Find ways to disperse pollen: wind, insects, birds, small mammals

Problems Land Plants Need to Solve

4. How to have Reproduction NOT dependent on water?

c. Keep developing embryo from

drying out with seed coat