How do plants survive in the environment?

Stimulus

Anything in an environment that causes a living thing to respond

GravityLightWater

- We close our eyes when the light is directed at us.

When we put water for plants, they grow.

Gravity always pulls us down to the earth again when we jump up high.

Tropism

It is the response of a plant to something in its environment

Plants respond to water by:

- Growing their roots toward the water’s resource.

- Example:Mangrove tree

Bending towards the source of light through chemicals found in the tip of their shoots.

Example:

Plants respond to light by:

Roots grow downwards “to the same direction as the pull of the gravity”, but stems grow upwards

“opposite to the direction of the gravity”

Plants respond to gravity by:

Adaptation

Structure or a behavior that helps a living thing to survive

in its environment

Adaptation in the Desert

Cactus plantStem-It has soft tissues that

hold water like a sponge.- It also has a thick, waxy cover to keep the water inside.- It has sharp spines that protect it from being eaten by animals.

Adaptation in the Forest

Tropical rainforest

- In the tropical rainforest, there are many trees & leaves growing next to each others, so they can block ‘prevent” the sun light from reaching to the plants at the bottom.

- So plants at the bottom adapt by having large leaves to catch the sun light.

- Tropical rainforests get much rain all the year, this too much rain can damage the leaves, so there is a drip tip at the end of each leaf to help rain water to fall off quickly.

Tropical rainforest

- Temperate forests don’t have much rain as

the tropical rainforest, so trees in the

temperate forest adapt by losing their

leaves in the fall to save water.