Seed plants and structure of a

seed

Warm up• What is the difference between vascular and non-

vascular plants?• Specify what type of plant is each of the

following:

Introduction • If plants can’t move, how do they spread their

seeds?• What are the two types of plants that you know

which make seeds?

Objectives • Describe three ways that seed plants differ

from seedless plants.• List three characteristics of seed plants.• Define pollen• Describe the structure of seeds.• Compare angiosperms and gymnosperms.• Recognize xylem and phloem as the main

vascular tissues in plants.• List three functions of roots.• List three functions of stems.

Seed plant

Vascular plants

Gymnosperms Angiosperms

Nonflowering plantsNo fruits

Ex: trees and shrubs

Flowering plantsFruits

Ex: grass and fruit trees

Characteristics of a seed plants

• Seed plants produce seeds.• Seeds nourish and protect young sporophytes.

Characteristics of a seed plants

• The gametophyte of seed plants don’t live independently of the sporophyte. The gametophytes is small and form within the reproductive structures of the sporophyte.

Characteristics of a seed plants

• The sperm of seedless plants need water to swim to the eggs of female gametophyte. Whereas, the sperm of the seed plants are formed inside pollen

• Pollen can be transported by wind or by animals.• 1- List three characteristics of seed plants

Structure of a seed

• A seed is formed after fertilization, when a sperm and an egg join.

• A seed is made up of three parts:1- young plant or the sporophyte2- stored food in the cotyledon3- seed coat which surrounds and protects the seed.

Advantages of seed plants

Seed plants Seedless plants

1- when growing, young plants used food stored in the seed

1- spores don’t have stored food to use when they grow

2- seed plants are spread by animals

2- spores are spread by wind

C.T: 2- how being eaten by an animal help a seed to grow?

Comparison between gymnosperms and

angiospermsGymnosperms Angiosperms Non-flowering plants. No fruits Flowering plants, most abundant

type of plants

Seeds are usually protected by a cone

Seeds are protected by the fruits.

Used for building material, paper, resin, and medicines

Used for food, medicines, fibers for clothing, rubber, and building materials.

Structure of seed plants

Plants

Root system Shoot system

Made of roots Made of stem and leaves

Pollination and fertilization

• What is the main difference between vascular and nonvascular plants?

Vascular tissue

Xylem Phloem

Move material from roots to shoots (stem

and leaves)

Move material from leaves to all plant

parts

Found in all plant parts

Roots • Most roots are underground• Roots supply plants with

water and dissolved minerals.

• They support and anchor plants.

• Roots also store surplus food made during photosynthesis. The food is produced in the leaves where it is transported by the phloem to the roots where it is stored as sugar or starch.

Stems • Stems are very various in shape

and size.• Usually located above the ground,

however some can be underground.• Stems support the body of a plant. • They allow transport of material

between the root system and shoot system, (contain xylem and phloem).

• Some stems store materials, such as water.

Wrap up