Angiosperms Angiosperms are the most diverse and geographically

Angiosperms • Angiosperms are the most diverse and geographically most widespread plants • Have flowers and fruits with seeds • Two classes: • 1. Monocotyledones (monocots) • 2. Dicotyledones (dicots) • Insect pollination tightly linked to evolution of the flower.

Angiosperms • Ecological Success of the Angiosperms – Able to survive in a greater variety of habitats than any other group of plants – Faster life cycle - mature more quickly than ferns or gymnosperms – Most produce greater number of seeds per year than gymnosperms – Animals aid in pollination - can survive as small scattered populations

Angiosperms • Fruits for seed dispersal • Most diverse and specialized group – perennials or annuals – Leaves of angiosperms are thin blades, diversity of shapes, better adapted for light interception. – Xylem of angiosperms contains wide-bore vessels, allows faster conduction of water. – Woody tissue of angiosperms more complex and highly specialized

Angiosperms From the Greek Angeion = vessel Sperma = seed

Monocot vs. dicot • As the zygote grows into the embryo, the first leaves of the young sporophyte develop and are called as cotyledons (seed leaves) • Monocots have one cotyledon (corn, lily, etc). • Dicots have two cotyledons (bean, oak, etc).

Monocot vs. dicot • Number of cotyledons: one vs. two

Monocot vs. dicot • Leaf venation pattern: • Monocot is parallel • Dicot is net pattern

Monocot vs. dicot root • Monocot: Fibrous root • Dicot: Tap root

Monocot vs. dicot • Flower parts: • Monocot: in groups of three • Dicot: in groups of four or five

Monocot vs. dicot • Monocot: Vascular bundle position: • Dicot: arranged in a circle

2 groups of Angiosperms • Monocot

Summary: Monocot vs. dicot

Plants 1 bud leaf flower 5 4 2 stem roots 3

Leaves: • Make food for plants which is sugar • Take in carbon dioxide through tiny openings in the leaves

Roots: • Hold the plant in the ground • Take in water and nutrients for the plant’s growth

The Stem: • holds up the plant parts above the ground. • has tiny tubes to transport water and nutrients to the plant’s parts.

What about flowers? • Flowers are made of petals. • Petals attract insects to the flower. • The flower makes seeds.

The life cycle of a plant 2. Leaves 3. More leaves start to grow. Flower 1. Roots buds appear. 4. The flowers grow from open. a seed.

Xylem & Phloem • Vascular tissue that moves water, minerals and nutrients from the roots to all parts of the plant

Angiosperm Basics • all have flowers • flowers are reproductive organs • They make up around 80 percent of all the living plant species on Earth.

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male part of flower • Angiosperms have male sex organs called stamens. • On the end of the stamen is the anther. This is where pollen is made. • The pollen has to be taken to the pistil or the female part of the flower.

female part of flower • The pollen is left on the stigma at the end of the pistil. • The stigma carries the pollen down a tube called the style to the ovary. • eggs are fertilized and develop into a seed in an ovary that is usually in a flower.

Pollination • Some plants can cross pollinate. This means they can pollinate themselves. • Others rely on pollinators. • Most species offer a nectar or pollen reward to insects or birds to attract them to the flowers. The colors and scents of flowers often assist pollinators in finding plants

From seed to Fruit After fertilization the embryo begins growing. The result is a seed. • The ovary {tissue immediately surround the seed or seeds} will develop into a fruit • Every angiosperm, produces some type of fruit • Fruit serves to disperse the seeds the plant produces, which is very important.

• When a plant flowers and produces seeds, it also produces something else we all like -- fruit. As you learned, when the ovary ripens, it swells and forms a protective covering around the seeds. This protective covering, or fruit, often finds its way on top of cereal, ice cream, a salad, or just a tasty snack.

Seeds • The seed's plant-parts are not "true" leaves, stem and roots, but are effective enough to the launch the plant into its growth phase when true leaves, roots and stems appear.

Seeds • Hidden inside every seed is a tiny embryonic plant complete with root, stem and leaves, ready to sprout when suitable conditions appear

What is their job? make food from light, air and water. Petals get water from the soil. Stems help the plant stand up. Leaves attract insects. Roots Flowers take food and water to the leaves make seeds.