unit 4 lesson 3 how do plants grow and reproduce? nonvascular plants vascular plants spore...

Unit 4 Lesson 3 How Do Plants Grow and Reproduce?Nonvascular plants

Vascular plantsSpore

GymnospermAngiospermGerminate

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Unit 4 Lesson 3 How Do Plants Grow and Reproduce?

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• Nonvascular plants are simple plants that lack vascular tissue, which easily transports water from the ground into the plant.

• They grow in damp places and almost never grow taller than 10 cm.

• Nonvascular plants move materials by absorbing nutrients and water in the same way that a sponge absorbs water.

http://www.youtube.com/watch?v=twMWq_9FgmU

http://www.youtube.com/watch?v=kBPLKUTtXBM


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• Vascular plants have vascular tissues that allow them to move water, nutrients, and sugars across long distances.

• Vascular tissue contains tiny tubes, which move water and nutrients up a plant in the same way that water moves up a straw.

• Most plants, including trees, grasses, and shrubs, are vascular plants.

http://www.youtube.com/watch?v=lVt_ACnSgOE


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• Vascular plants have true leaves and roots.

• Vascular tissue includes two kinds of smaller tubes. Xylem carries water and nutrients from the roots to the other parts of the plant.

• Phloem carries sugar from the leaves to the rest of the plant.

http://www.youtube.com/watch?v=lVt_ACnSgOE


No Seeds, Please!


• A spore is a single reproductive cell that can grow into a new plant.

• Both nonvascular plants, such as mosses and liverworts, and vascular plants, such as ferns, use spores to reproduce.

http://www.youtube.com/watch?v=-xF83pHEx6Q


No Seeds, Please!


• All of these plants have a sexual generation and an asexual generation in their life cycles.

• For example, the sexual generation of moss has male parts producing sperm and female parts producing eggs. When sperm and egg combine, the fertilized egg grows into a stalk.


No Seeds, Please!


• The stalk is the asexual generation of moss. A capsule grows at the end of the stalk, forming spores that shoot out when the capsule opens.

• These spores land on the ground and develop into threadlike plants that form buds, which turn into green “leafy” structures.

• The “leafy” sexual generation of moss, the most familiar form of the plant, makes food and root-like structures that anchor the plants to the ground.


No Seeds, Please!


• Like mosses, ferns also use spores to reproduce. In ferns, the reproductive spores form inside clusters on the underside of the leaflets.

• The spores are released and fall to the ground when the pockets burst.

• The spores then grow into a tiny fern plant. This structure releases sperm and egg cells that, once fertilized, grow into a young fern.


No Seeds, Please!


• The young fern grows into the large, upright fern plant, called the frond. This is the asexual generation of the fern.

http://www.youtube.com/watch?v=9c9Zi3WFVRc


Seed Power!


• While spores need to stay moist and sprout soon after release, seeds have a covering that protects them until conditions are right for sprouting.

• Gymnosperms are plants that do not produce seeds in flowers. Gymnosperm seeds have a protective seed coat, but are not enclosed by fruit.

• Cone-producing plants, called conifers, are the most common gymnosperms. Conifers include pine, fir, spruce, and cedar trees.


Seed Power!


• Angiosperms are plants that produce seeds in flowers.

• Since angiosperm seeds are often enclosed in fruit, they are easily spread when animals eat the fruits.

• Gymnosperm seeds may also be spread by animals, but typically fall to the ground and grow where they land.


From Flower to Fruit to Seed


• Typical flowers have both male and female reproductive parts.

• A male part, the anther, produces pollen, or the sperm.

• The female parts include the stigma and the ovary, which contains eggs in ovules.




• Flowers produce nectar that organisms may eat. When an organism gathers nectar, pollen may brush onto it.

• The organism carries this pollen when it moves to the next flower. This process is called pollination.

• When the pollen reaches the stigma, it travels down to the ovary and fertilizes the ovules. This process is called fertilization.




• Fertilized ovules develop into seeds, and the ovule wall becomes a seed coat. The ovary that holds the seeds develops into the fruit, such as a pumpkin.

• The development of a pumpkin seed into a mature pumpkin fruit follows a sequence of events.




• Pollen enters the flower’s ovary and fertilizes the ovules. The ovary grows and the petals fall off. The ovules develop into seeds inside the ovary.

• Finally, the outer layer of the ovary thickens to form a fruit around the seeds. The mature pumpkin is filled with seeds.




• Identify the following parts of a flower: anther, ovary, ovules, petals, stigma.

How Seeds Grow


• Seeds have a hard outer coat that protects them and allows them to rest until the environment is right for growing.

• Many plant seeds rest during winter and then germinate, or start to grow, when the ground becomes warm and moist in the spring.

• A dormant seed lies in the soil until conditions are right for growing. The seed germinates by absorbing water and breaking through the seed coat.


How Seeds Grow


• The embryo continues to grow and a stem pushes upward. Cotyledons provide energy for growth and roots form and begin growing downward.

• Leaves mature and the plant starts absorbing more energy from sunlight. It continues to grow as the shoot pushes upward.

• The plant grows and matures until it produces flowers and fruit.


http://www.youtube.com/watch?v=G2RuVxdr0mA

unit 4 lesson 3 how do plants grow and reproduce? nonvascular plants vascular plants spore...

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