Agriculture
Fast-flying fungal spores
Got Milk? How?
Earth-Friendly Fabrics
Amphibians
Salamanders and Newts
Toads
Bullfrogs
Animals
Helping the Cause of Macaws
A Butterfly's New Green Glow
Who's Knocking?
Behavior
Slumber by the numbers
Storing Memories before Bedtime
Island of Hope
Birds
Songbirds
Finches
Mockingbirds
Chemistry and Materials
A Framework for Growing Bone
A Light Delay
Moon Crash, Splash
Computers
Look into My Eyes
Earth from the inside out
The science of disappearing
Dinosaurs and Fossils
Digging Dinos
Middle school science adventures
Tiny Pterodactyl
E Learning Jamaica
E Learning in Jamaica WIN PRIZES and try our Fun Animated Games
2014 GSAT Results for Jamaican Kids
Results of GSAT are in schools this week
Earth
Greener Diet
Undersea Vent System Active for Ages
Killer Space Rock Snuffed Out Ancient Life
Environment
Ready, unplug, drive
The Oily Gulf
To Catch a Dragonfly
Finding the Past
Fakes in the museum
A Plankhouse Past
If Only Bones Could Speak
Fish
Freshwater Fish
Great White Shark
Skates and Rays
Food and Nutrition
Yummy bugs
The Essence of Celery
A Pepper Part that Burns Fat
GSAT English Rules
Pronouns
Order of Adjectives
Adjectives and Adverbs
GSAT Exam Preparation Jamaica
March 21-22, 2013: Over 43,000 students will take the GSAT Exam
42,000 students will sit for the GSAT Exam in two weeks
The Annual GSAT Scholarships
GSAT Exams Jamaica Scholarships
Results of GSAT are in schools this week
Access denied - Disabled boy aces GSAT
GSAT Practice Papers | GSAT Mathematics | Maths
GSAT Mathematics
Losing with Heads or Tails
Detecting True Art
GSAT Practice Papers | GSAT Mathematics | Maths
Human Body
Disease Detectives
Running with Sneaker Science
Football Scrapes and Nasty Infections
Invertebrates
Nautiluses
Sponges
Corals
Mammals
African Jackal
Chihuahuas
Yaks
Parents
Choosing a Preschool: What to Consider
The Surprising Meaning and Benefits of Nursery Rhymes
Raise a Lifelong Reader by Reading Aloud
Physics
Electric Backpack
Echoes of a Stretched Egg
Einstein's Skateboard
Plants
Surprise Visitor
Cactus Goo for Clean Water
Tracking the Sun Improves Plant Pollen
Reptiles
Lizards
Iguanas
Geckos
Space and Astronomy
A Darker, Warmer Red Planet
Pluto, plutoid: What's in a name?
A Smashing Display
Technology and Engineering
Musclebots Take Some Steps
Are Propellers Fin-ished?
Morphing a Wing to Save Fuel
The Parts of Speech
What is a Noun
Adjectives and Adverbs
Problems with Prepositions
Transportation
Troubles with Hubble
How to Fly Like a Bat
Charged cars that would charge
Weather
In Antarctica watch the heat (and your step)
Catching Some Rays
A Change in Climate
Add your Article

Earthworms

Earthworm is the common name for the larger members of the Oligochaeta in the phylum Annelida. Folk names for earthworm include "dew-worm", "night crawler" and "angleworm". Earthworms have a closed circulatory system. They have two main blood vessels that extend through the length of their body: a ventral blood vessel which leads the blood to the posterior end, and a dorsal blood vessel which leads to the anterior end. The dorsal vessel is contractile and pumps blood forward, where it is pumped into the ventral vessel by a series of "hearts" which vary in number in the different taxa. A typical lumbricid will have 5 pairs of hearts. The blood is distributed from the ventral vessel into capillaries on the body wall and other organs and into a vascular sinus in the gut wall where gases and nutrients are exchanged. One often sees earthworms come to the surface in large numbers after a rainstorm. There are two theories for this behavior: The first is that the waterlogged soil has insufficient oxygen for the worms, therefore, earthworms come to the surface to get the oxygen they need and breathe more easily. However, earthworms can survive underwater for several weeks if there is oxygen in it, so this theory is rejected by some. Secondly, the worms may be using the moist conditions on the surface to travel more quickly than they can underground, thus colonizing new areas more quickly. Since the relative humidity is higher during and after rain, they do not become dehydrated. This is a dangerous activity in the daytime, since earthworms die quickly when exposed to direct sunlight with its strong UV content, and are more vulnerable to predators such as birds. Earthworms are hermaphrodites (both female and male organs within the same individual) but generally cannot fertilize their own eggs. They have testes, seminal vesicles and male pores which produce, store and release the sperm, and ovaries and ovipores. However, they also have one or more pairs of spermathecae (depending on the species) that are internal sacs which receive and store sperm from the other worm in copulation. Copulation and reproduction are separate processes in earthworms. The mating pair overlap front ends ventrally and each exchanges sperm with the other. The cocoon, or egg case, is secreted by the clitellum, the external glandular band which is near the front of the worm, but behind the spermathecae. Some indefinite time after copulation, long after the worms have separated, the clitellum secretes the cocoon which forms a ring around the worm. The worm then backs out of the ring, and as it does so, injects its own eggs and the other worm's sperm into it. As the worm slips out, the ends of the cocoon seal to form a vaguely lemon-shaped incubator (cocoon) in which the embryonic worms develop. They emerge as small, but fully formed earthworms, except for sexual structures, which develop later. Some earthworm species are mostly parthenogenetic, in which case the male structures and spermathecae may become abnormal, or missing.

Earthworms
Earthworms








Designed and Powered by HBJamaica.com™