Agriculture
Chicken Eggs as Drug Factories
Keeping Bugs Away from Food
Silk’s superpowers
Amphibians
Salamanders
Toads
Bullfrogs
Animals
Cool Penguins
Insects Take a Breather
Roach Love Songs
Behavior
Fish needs see-through head
The Colorful World of Synesthesia
Dino-bite!
Birds
Woodpecker
Peafowl
Ospreys
Chemistry and Materials
Watching out for vultures
Salt secrets
Atomic Drive
Computers
A Light Delay
The science of disappearing
Galaxies on the go
Dinosaurs and Fossils
Hunting by Sucking, Long Ago
A Dino King's Ancestor
Big Fish in Ancient Waters
E Learning Jamaica
Results of GSAT are in schools this week
2014 GSAT Results for Jamaican Kids
E Learning in Jamaica WIN PRIZES and try our Fun Animated Games
Earth
Giving Sharks Safe Homes
Plastic-munching microbes
Getting the dirt on carbon
Environment
The Best Defense Is a Good Snow Fence
Pollution Detective
Whale Watch
Finding the Past
Prehistoric Trips to the Dentist
Stone Age Sole Survivors
Writing on eggshells
Fish
Parrotfish
Flashlight Fishes
Saltwater Fish
Food and Nutrition
Recipe for Health
The Color of Health
Symbols from the Stone Age
GSAT English Rules
Problems with Prepositions
Who vs. Whom
Finding Subjects and Verbs
GSAT Exam Preparation Jamaica
GSAT Exam Preparation
Results of GSAT are in schools this week
E Learning in Jamaica WIN PRIZES and try our Fun Animated Games
GSAT Exams Jamaica Scholarships
42,000 students will sit for the GSAT Exam in two weeks
Access denied - Disabled boy aces GSAT
Results of GSAT are in schools this week
GSAT Mathematics
Setting a Prime Number Record
How a Venus Flytrap Snaps Shut
Math is a real brain bender
Human Body
Dreaming makes perfect
Surviving Olympic Heat
Tapeworms and Drug Delivery
Invertebrates
Snails
Crustaceans
Sea Urchin
Mammals
Gazelle
Quolls
Wolves
Parents
Raise a Lifelong Reader by Reading Aloud
Choosing a Preschool: What to Consider
Expert report highlights the importance to parents of reading to children!
Physics
Project Music
Einstein's Skateboard
Black Hole Journey
Plants
When Fungi and Algae Marry
Underwater Jungles
Seeds of the Future
Reptiles
Garter Snakes
Iguanas
Crocodilians
Space and Astronomy
Icy Red Planet
A Very Distant Planet Says "Cheese"
Planets on the Edge
Technology and Engineering
Smart Windows
A Clean Getaway
Musclebots Take Some Steps
The Parts of Speech
Countable and Uncountable Nouns
Pronouns
What is a Preposition?
Transportation
Ready, unplug, drive
How to Fly Like a Bat
Troubles with Hubble
Weather
Recipe for a Hurricane
A Dire Shortage of Water
Weekend Weather Really Is Different
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™