Lesson 15 reproduction from roots leaves and stems

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Transcript of Lesson 15 reproduction from roots leaves and stems

Reproduction from Roots, Leaves and

Stems

Reproduction asexual reproduction

Bulb Tuber Runner spread out stretch out Geranium Stem cutting Layering Grafting

Розмноження Безстатеве

розмноження Цибулина (луковиця) Бульба Вусик Розтягуватися Тягтися Герань стовбурові різання розшарування щеплення

Any reproduction that occurs without the combining of male and female sex cells or sex nuclei is calledasexual reproduction.

Shoots growing from roots

Sweet potatoes are the roots of flowering plants.

New shoots will readily grow from a sweet potato.

The leaves of some plants can also grow into new plants.

Many plants have special stems that allow them to reproduce asexually.

Onion plants can reproduce asexually by using bulbs, which grow underground.

Most of the bulb is made up of tightly packed leaves that store food.

Other common plants with bulbs are:

Tulips

Lilies

Daffodils

A potato is a tuber that grows underground.

A tuber is a thick stem with buds that can grow into a new plant.

The buds of the tuber are the “eyes” you cut out of a potato before you cook it.

New plants grow from the buds when a potato is planted.

Dahlias and peonies can also

reproduce by tubers.

The strawberry plants are connected by a runner which is a stem that grows across the top of the soil.

New strawberry plants grow at points where the runner touches the ground.

Strawberries spread out in a field because these runners stretch out in all directions.

How can plants reproduce?

They can reproduce by …

Asexual Reproduction in Plants Is Important!

There are three types of asexual reproduction:

Stem cutting

Layering

Grafting

Stem cuttings are branches that are cut off a plant and placed in water or soil.

This method is used in greenhouses to quickly grow

geraniums.

When plant growers use the layering method, they cover a branch containing one or more buds, with soil.

The buds on some of the covered branches may grow into new plants.

Sometimes plant growers cut off the top part of a plant and attach it to the root system or stem of another plant.

This method is called grafting.

The advantage of grafting is that a new plant is made by joining the good parts of one plant to the good parts of another.

One kind of rose bush, for example, may have good roots, but it may not have pretty flowers.

Another kind of plant may have beautiful flowers, but poor roots.

How many ways of reproduction flowers do you know?