Plants

Chapter 2

A Plant Cell’s Unique Organelles

• Cell Wall• Chloroplasts• Chlorophyll• A single vacuole

What do plants need to survive?

• Sunlight• Water• Nutrients and

minerals

How do plants take in materials?

• Take in water through the roots

• Root hairs: threadlike cells that grow from a plant root and takes in water and minerals from the soil

Moving Materials to Different Plant Parts

• There are tubes that carry water, food, and minerals through the plant.

• One tube brings water up.

• One tube brings food and minerals down.

• An elevator!

TRANSPIRATION

• Transpiration is the evaporation of water through the leaves.

• Stomata: openings in the leaf through which gases and water enter and leave.

• Water leaves the plant through the stomata.

• Gases enter the plant through the stomata.

Transpiration

• http://techalive.mtu.edu/meec/module01/Transpiration.htm

Photosynthesis

• Photosynthesis is the process by which plants make sugar from sunlight, water, and carbon dioxide.

• For this to occur, plants need:1. Sunlight

2. Water

3. Carbon Dioxide

Photosynthesis

Steps of Photosynthesis

1. Chloroplasts trap the light energy (sunlight).

2. Water enters the leaf.

3. Carbon dioxide enters the cell through the stomata.

4. Sugar leaves the leaf and travels to the rest of the plant.

Respiration

• Respiration is the process by which cells change sugar and oxygen into carbon dioxide and water (energy).

• This is how the plant breaks down the food (sugar) into a form it can use!

• Cells use this energy to do their work.

A Flowering Plant

• Important parts:– Stamen: male part of

the flower that produces pollen

– Pistil: female part of the flower that contains the egg

Fertilization vs. Pollination

• Fertilization: takes place when the male gamete from the pollen joins the female gamete in the ovary.

• Pollination: any process that delivers pollen to eggs in plants (this is the first step in fertilization!!)– What are some ways that pollination can

occur?

Life Cycle of Flowering Plant

1. Pollen sticks to pistil. Pollen tube grows into ovule.

2. Sperm fertilizes egg cell.

3. Egg cell becomes a seed.

4. Ovule grows into a fruit that covers seed.

5. Seed grows into a new plant.

Fertilization

• http://player.discoveryeducation.com/index.cfm?guidAssetId=FC424D65-D3BE-4A4E-B564-B77B5A8911A4&blnFromSearch=1

Life Cycle of Conifers

• Conifers: plants that make seeds in cones

• Most are trees and shrubs with leaves like needles.

• 2 types of cones:1. Pollen cones

2. Seed cones

Conifer Life Cycle

1. Pollen spreads through air and sticks to seed cone.

2. Sperm fertilizes egg cell.

3. Egg cell grows into a seed.

4. Seed grows into a new plant.

Ferns

Life Cycles of Seedless Plants

• Some plants do not make seeds!!

• These plants never have flowers or cones.

• Examples: moss and ferns

• Spores: a tiny cell that can grow into a new plant.

Spore cases

Life Cycles of Fern

1. Spore cases open.

2. Spore begins growing into young fern plant.

3. Sperm swim to egg cells of young fern plant.

4. Fertilized egg cell grows into new plant part.

5. New plant part grows into fern.

What is a plant adaptation?

• A plant adaptation is – a change in a plant’s structure – occurring over a long period of time– makes the plant able to live in a particular

area

How have these plants adapted?