Reproduction in plants 1. Sexual reproduction A. Reproduction in flowering plants Sexual reproduction takes place inside the flower. Flowers are the reproductive organs. - Male organs: The stamen is the male reproductive organ: * The anther produces pollen. Pollen is the male reproductive cell. * A long thin filament supports the anther.

- Female organs: The pistil is the female reproductive organ: * The stigma traps (atrapa) pollen. * The style is a connection tube. * The ovary contains ovules inside. An ovule is the female reproductice cell. When the ovule is fertilised, it becomes a fruit. - Classification of flowers: * The male flower produces pollen. * The female flower produces ovules. * In an hermaphrodite flower, the male and female parts are inside the same flower.

Fertilisation Wind, insects… can transport pollen from one flower to another. Flowers have brightly coloured petals that attract insects. Pollination occurs when the pollen fertilises the ovule. This is called fertilisation. Then the ovary becomes (Se convierte) the fruit and the ovule becomes the seed. When the seeds fall to the soil and germinate, a new plant grows (crece).

Pollination can be: - self-pollination: pollen is transferred from one flower to another of the same (misma) plant. - Cross-pollination: the pollen is trasnferred to a different plant of the same type. B. Reproduction in non-flowering plants Non-flowering plants dont have flowers or seeds. They use spores to reproduce. Sori are sacks that contain thousands of spores. They are located under the leaves. Spores fall to the soil and form organs that produce reproductuve cells.

2. Asexual reproduction In fragmentation, a new plant grows from a fragment of a plant. There are different types of fragments: - Stolons are above ground (por encima del suelo) stems that grow horizontally. As they grow, they develop roots. Ex: strawberries. - Cuttings are stems that produce new roots when they are separated from the parent plant. Ex: Geraniums. - Tubers are underground stems. Ex: Potatoes - Bulbs are at the bottom of the stem. They grow underground. Each bulb gives a new plant. Ex: Garlic. - Rhizomes are underground stems that grow horizontally. Ex: Asparagus.

Plants respond to their environment There are two ways plants can move: - Nastic movements: the movement doesn’t involve (no implica) growth (crecimiento). Ex: A carnivorous plant. - Tropic movements: plants move towards (hacia) or away a stimulus (estímulo) and involve (implica) growth. -* Phototropism: the plant grows towards sunlight. -* Hidrotropism: the roots grow towards the water. -* Gravitropism: plants react to gravity so (asi que) roots always grow down into the soil. Plants also respond to environmental changes (cambios del medio ambiente): light, temperature and humidity. Some trees are deciduous (de hoja caduca) and lose (pierden) their leaves in the cold seasons.