Plant Responses and Adaptations

Plant Adaptations Adaptations help plants survive (live and grow) in different areas(biomes). Adaptations - features that allow a plant or animal to live in a particular place or habitat.

Adaptations of Plants Absorbing Nutrients –absorb mineral nutrients from soil. (roots) Preventing Water Loss -cuticle – watertight, waxy outer covering -epidermis – outer layer of plant -stomata –small openings guard cells – cells around stomatas which help them to open. Reproducing on Land –use pollen to reproduce

Adaptations of Plants 4. Advantages of Conducting Tissues - Vascular plants have tissues that transport water and nutrients. 5. Advantages of seeds - Protection - Nourishment - Dispersal - Delayed growth 6. Advantages of Flowers – Color/ scent help with pollination (reproduction)

What are some adaptations in different habitats?

Desert Adaptation This plant has a waxy coating on its leaves to prevent water loss. This cactus displays light-colored hair that helps shade the plant and hair to help shade the plant, reducing water loss.

Tropical Rainforest Plant Adaptation Drip-tips on leaves help shed excess water. Broad leaves help get sunlight. Prop roots help support plants in the shallow soil.

Temperate Rainforest Plant Adaptation   Epiphytes live on other plants to reach the sunlight. Trees can grow very tall in this very moist environment.

Temperate Deciduous Forest Wild flowers grow in the spring before trees grow their leaves. In the autumn, deciduous trees drop their leaves to minimize water loss.  

Temperate Deciduous Forest Plant Adaptations Many trees have thick bark to protect against cold winters . Broad leaves can capture a lot of sunlight for a tree.

Plant Growth & Responses

Hormone-producing cells A. Hormones in Plants 1. Plant cells produce hormones, which are chemical messengers, that travel throughout plant causing other cells called target cells to respond. 2. In plants, hormones control: Plant growth & development Plant responses to environment Flower Blooming Movement of hormone Target cells Cells in one blooming flower signals other blooms using hormones to open.

B. Plant cells will send signals to one another to tell them: When trees to drop their leaves. When to start new growth. When to cause fruit to ripen. When to cause flowers to bloom. When to cause seeds to sprout. Sprouting Corn Seeds Tree Budding Fruit Ripening Cactus Blooming Leaf Drop

Important Hormones Gibberellins - responsible for plants growing into adult plants and flower growth Ethylene – causes fruits to ripen Auxins - responsible for geotropisms and phototropisms Ethylene released by apples and tomatoes causes fruit to age quickly.

D. Plant Tropisms Tropism: the way a plant grows in response to stimuli in the environment. Phototropism: growth response to light Plants bend towards light Gravitrophism: growth response to gravity plant roots grow down with gravity, shoots (stems) grow up against gravity and out of the soil. Also called geotrophism Thigmotropism: growth response to touch vines grow up around trees, Venus flytrap closes when leaves are touched

Phototropism Gravitropism Slide # 23 What type of tropism is shown in these pictures? Phototropism Gravitropism Phototropism Thigmotropism Gravitropism Thigmotropism

Plants in our lives Fruits and vegetables Crops Wood medicine Fibers