Earthworms Virtual Dissection

Bring a bag, looking at this will make you use it.

Objectives

Background

  • Taxonomy

Earthworm's specific name is Lumbricus terrestris.

The scientific classification of an earthworm is Oligochaeta. Earthworms are hermaphrodites, which means that they have both male and female sex organs. Earthworms are also invertebrates, meaning they do not possess a skeleton.

Kingdom: Animalia

Phylum: Annelida

Class: Clitella

  • Evolution

Earthworms have a brown slimy skin that can camouflage with the soil to avoid detection. Earthworm's response to the environment by mostly hiding from the sun, it sense the sun as dangerous because it makes the earthworm less moist and if the earthworm is out on in the sun for a long time, it becomes dry.

  • Ecology

Earthworms can live anywhere that has rich soil for them. Their predators can be any organisms that are common, birds, mouse, moles, or other insect that are bigger. An earthworm's prey is bacteria. The trophic level is at 5.0. The earthworm's niche is decomposing the soil. A flower and an earthworm's symbiotic relationship mutualism, earthworms provides air for plants by making air tunnels.

Earthworm Cladogram

http://media1.shmoop.com/images/biology/biobook_taxonomy_graphik_14.png

Population Density

http://tropecol.com/pdf/open/PDF_44_2/44210.pdf

Body Systems

http://staff.tuhsd.k12.az.us/gfoster/standard/bworm.htm

Oragn Functions (Internal)

  • Mouth- take in the nutrients
  • Brain- movement (thoughts)
  • Pharynx- swallows the food
  • Seminal Receptacles- container for semen
  • Seminal Vesicles- where the sperms are produced
  • Esophagus- moves the food from the pharynx to the crop
  • Oviduct- receives the opposites worm's sperm
  • Gizzard- chews the nutrients
  • Ventral blood vessels- pumps blood on the ventral side
  • Intestines- To process food and extract nutrients
  • Hearts- pumps blood
  • Calciferous glands- regulates the calcium and PH in an Earthworm's blood.
  • Crop- the crop is used to store food
  • Dorsal Blood Vessels- vessels connects to all the parts of the body on the dorsal side
  • Typhlosole-more efficent absorption of digested nutrients
  • Pseudo hearts- fake hearts that also pump blood around the body

http://www.biologycorner.com/resources/earthworm_external_answers.JPG

External Organs of a Earthworm

Segments- excretion and digestion of waste

Setae- helps the earthworm to move

Clitellum- produce a sac that eggs can be deposited in

Anus- where waste leaves the organism's body

Sperm ducts- stores the sperm

Oh, so you are not disgusted?

If you want to dissect earthworms on your own, you can find them in your back yard, but just make sure you ask your parents before digging up their garden.

http://www.blogcdn.com/www.diylife.com/media/2008/05/2328653836_b22f33de10.jpg

THE MORE YOU KNOW>>>FACTS

  • When earthworms tunnel through the ground they bring air into the soil. This allows plant roots to grow more easily.
  • More than 3,000 species of earthworm exist in the world
  • Worms can have between 1-5 pairs of hearts.
  • The earthworm does not have lungs and instead uses its skin to breath
  • Worms are cold blooded and their body is made up of 80% water
  • Worms typically live for about 3-4 years, however there have been some cases where they have lived for 15 years.

http://www.infobarrel.com/Top_10_facts_about_Worms

SAVE THE EARTHWORMS

Humans, yes you, you guys have made some big mistakes that kill earthworms by dumping chemical waste into the soil. Help them out and be sure to water your front, and backyard, but not too much. Earthworms may leave the soil because of too much water. Water holds much less oxygen than air and earthworms rely on the air in the soil for diffusing adequate oxygen through their skin. Earthworms can help your plants look nice by making holes in the soil and plant can take in more air, its a win-win for every organism.

http://gardenvarietynews.files.wordpress.com/2014/03/watering-the-garden.jpg?w=640&h=440

THE DIGESTIVE SYSTEM OF AN EARTHWORM

The earthworm biology basically consists of an elongated, cylindrical body that is metamerically segmented. A thin cuticle, epidermis and musculator makes up the body wall. The prostomium or mouth of an earthworm is made up of strong lips. The buccal cavity is made up of 2½ segments that is thin-walled and shaped like a pear. There are no jaws and teeth and the earthworm sucks in the soil containing food with the muscular pharynx. The food is lubricated with the mucus secretions on the pharynx that helps it pass easily to the esophagus. The food is then passed on to the esophagus that is present in the 5th to 7th segment. The esophagus is like a small tube that has calciferous glands. The food then moves into the next chamber called the crop. The crop is where the food is stored till it can be moved to the next chamber, the gizzard. The gizzard is like a strong muscular food processor. It is also called the proventriculus and is found in the 8th segment. The waste is thrown out of the body through anus.

http://bio1152.nicerweb.com/Locked/media/ch41/digestive_systems.html