Shape: Earthworm is
elongated, long, narrow, cylindrical or vermiform shaped
. The anterior end is tapering while the posterior end is more or less blunt. Body surface: Body consists of dorsal and ventral surfaces.
What is this exterior part of the earthworm called?
The ‘head' or front of the earthworm is called its
anterior
.
What is the most obvious external structure of an earthworm?
The most notable external feature is
the segmentation of the body
, which is clearly visible in Figures 1-4. The first section of the worm, the anterior section or head, consists of the mouth and the prostomium.
What is the adaptive features of earthworm?
Earthworms are adapted for life underground. Their
streamlined shape allows them to burrow through soil
. They have no skeletons or other rigid structures to interfere with their movement. The earthworm's body is divided into segments.
What are the features of earthworm?
Earthworms are
soft-bodied, segmented worms
, usually pink, brown or red in color and only a few inches long. They burrow deep in the ground during the day and resurface at night to feed.
What are 2 characteristics of worms?
Characteristics. All worms are
bilaterally symmetrical
, meaning that the two sides of their bodies are identical. They lack scales and true limbs, though they may have appendages such as fins and bristles. Many worms have sense organs to detect chemical changes in their environments, and some have light-sensing organs.
What are the 5 characteristics of earthworm?
- Metamerism. All annelid bodies are divided serially into segments called metameres. …
- Body Wall. The body wall has an outer circular muscle layer and inner longitudinal muscle layer. …
- Chitinous setae. …
- Coelom. …
- Closed Circulatory System. …
- Complete Digestive System. …
- Respiration. …
- Excretory System.
What is worm skin called?
The clitellum
is a swelling of the skin and can only be seen in earthworms that are ready to reproduce. It may be white, orange-red or reddish-brown in colour. Earthworms are ready to mate when their clitellum is orange. Most of the material secreted to form earthworm cocoons is produced within the clitellum.
Why do earthworms have thin skin?
A moist surface is necessary for oxygen to be absorbed and carbon dioxide to be given off. The worm's skin is
protected by a thin cuticle and kept moist by a slimy mucus
. This lets it absorb the oxygen it needs and expel carbon dioxide.
What is the study of earthworms called?
Hence “
helminthology”
is the study of parasitic worms. When a human or an animal, such as a dog or horse, is said to “have worms”, it means that it is infested with parasitic worms, typically roundworms or tapeworms.
Which side of the worm is darker?
The dorsal surface of some species
of earthworms is darker than its ventral surface. The bottom-side of an animal is called the ventral surface. In many animals, the ventral surface is a lighter colour or shade than the dorsal surface.
What is that thing on a worm?
The clitellum is a thick, saddle-like ring found in the epidermis (skin) of the worm, usually with a light-colored pigment. … To form a cocoon for its eggs, the clitellum secretes a viscous fluid. This organ is used in sexual reproduction of some annelids, such as leeches.
How many hearts does a worm have?
Heartbeats: Worms don't have just one heart. They have
FIVE
! But their hearts and circulatory system aren't as complicated as ours — maybe because their blood doesn't have to go to so many body parts. Moving around: Worms have two kinds of muscles beneath their skin.
What is the importance of earthworm?
Earthworms play a huge
role in breaking down organic matter and fertilising soil
, they simply do this through their constant need to eat and excrete, producing ‘worm cast'. This worm cast is full of beneficial bacteria and nutrients which provides a healthy habitat for plants and other organisms.
How does an earthworm move for Class 6?
Earthworms move by
alternate extension and contraction of the body using muscles
. Tiny bristles on the underside of the body help in gripping the ground. Snails move with the help of a muscular foot. The body and legs of cockroaches have hard coverings forming an outer skeleton.
What are the adaptive features of snail?
Freshwater and marine snails have
evolved gills
, while terrestrial snails sport fully formed lungs. Golden apple snails have adapted by possessing both a lung and gills. They can absorb oxygen straight from the water or siphon air through a tube on the left side of the body.
