Bilingual Spanish jay

 This information has been taken from The Open Door Web Site.

Summary

Asexual Reproduction

• Asexual Reproduction : Reproducing without Sex Cells
• Asexual Reproduction in Single-celled Organisms
• Asexual Reproduction in Animals
• Vegetative Reproduction
• Vegetative Propagation

1. Sexual reproduction requires sex cells (sperms and eggs produced by males and females) but asexual reproduction requires no sex cells at all.
2. Asexual reproduction is common amongst plants, single-celled organisms and simple animals.
3. Asexual reproduction has the advantage of producing large numbers of offspring very quickly.
4. A group of offspring produced by asexual reproduction from a single parent is called a clone.
5. Asexual reproduction in a single-celled organism involves simply dividing into two or the budding of a small piece of the mother cell.
6. Simple animals, such as the Hydra, may also bud off small pieces which have grown from their bodies.
7. Green plants are quite sophisticated in their methods of asexual reproduction. Offspring may be produced by runners, bulbs, rhizomes or tubers.
8. Gardeners have used this ability of plants to reproduce asexually. They take cuttings from plants and encourage them to grow roots and leaves. In this way large numbers of the same plant can be obtained very quickly from one parent plant.
9. Scientists have gone one step further; they cultivate very small pieces of plants in test tubes. This is called in vitro culture and it can produce thousands of identical offspring from one plant, all grown under carefully controlled conditions.

Sexual reproduction or Asexual reproduction?

• Introduction
• Sexual Reproduction in Populations of Wild Animals and Plants

1. Asexual reproduction is quite rapid and requires only one parent.
2. The offspring produced by asexual reproduction, from the same parent, are all identical to one another and they are identical to the parent.
3. Sexual reproduction requires sex cells produced by two parents (a male and a female). Sexual reproduction is more complex and slower than asexual reproduction.
4. Offspring produced by sexual reproduction look like their parents but they are not identical (unless they are identical twins); they show variation.
5. Farmers breed together different varieties of animals or plants to produce offspring which show the best characteristics of both parents.
6. Amongst populations of wild animals and plants, species show variation as a result of sexual reproduction. This variation allows them to adapt to new environments.
7. If a species of organism which shows no variation cannot adapt it may become extinct.

Animal Reproduction

• Introduction to Animal Reproduction
• Mating and Fertilization
• Reproduction in Birds
• Reproduction in Mammals
• Different Ways of Growing

Reproduction in Flowering Plants

• Flowers and Reproduction
• The Structure of Insect Pollinated Flowers
• Pollinating Mechanisms
• Wind-pollinated flowers
• Fruits and Seeds
• Seed Germination

• Survival reactions
• Movements in unicellular organisms
• Animal responses
• Transmitting a nerve impulse
• Pheromones

Acabamos de empezar la función de relación en animales y plantas. He aquí dos interesantes presentaciones sobre los dos sistemas encargados del procesamiento y coordinación en los seres humanos.

The nervous sytem presentation from Biodeluna:

The endocrine system presentation from Biodeluna:

En este vídeo se resume todo lo que hemos aprendido hasta ahora sobre las plantas: sus células, su nutrición (fotosíntesis), su reproducción (alternancia de generaciones: gametofito y esporofito) y los grupos principales (helechos, musgos, gimnospermas y angiospermas o plantas con flores).