¡Bienvenidos! Recursos español y bilingüe sobre Ciencias Naturales, para alumnos de secundaria.
domingo, 1 de marzo de 2015
Earthworm dissection.
Because it is widely known, Lumbricus terrestris goes under a variety of common names. In Britain, it is primarily called the common earthworm or lob worm (though that name is also applied to a marine polychaete). In North America, the term nightcrawler (or vitalis) is also used. In Canada, it is also called the dew worm, or "Grandaddy Earthworm". Although this is not the most abundant earthworm, even in its native range, it is a very conspicuous and familiar earthworm species in garden and agricultural soils of the temperate zone, and is frequently seen on the surface, unlike most other earthworms. It is also used as the example earthworm for millions of biology students around the world, even in areas where the species does not exist.
Worms are critical for soil turnover and fertility. They eat dead plant material, and their burrows help aerate the soil and let water through easily. Worm casts (faeces) are rich in recycled plant nutrients that help maintain soil fertility.
This practise consists on two parts:
A) First, there is a theorical study of annelids, specifically earthworms (Lumbricus terrestris).
Complete your worksheet, using this page Earthworm virtual dissection to do the exercises.
In this link you have the Virtual earthworm dissection worksheet.
WITHOUT COMPLETING THIS WORKSHEET, THE STUDENT IS NOT DOING THE DISSECTION
B) The second part of this practice, consists on observing the external features of annelids, and the earthworm internal characteristics. The practice guide is available in both links.
Check this video of how to dissect an earthworm.
And this page about earthworms characteristics.