What is the basic structure and organs of the earthworm?

What is the basic structure and organs of the earthworm?

Earthworms have a complex digestive system consisting of the mouth, pharynx, esophagus, crop, gizzard, and intestine. These organs work together to pass soil that the worm ingests through its body. During the digestion process, nutrients are absorbed into the blood stream, and any leftover waste exits through the anus.

What structures are within each segment of earthworms?

Segmentation can help the earthworm move. Each segment or section has muscles and bristles called setae. The bristles or setae help anchor and control the worm when moving through soil. The bristles hold a section of the worm firmly into the ground while the other part of the body protrudes forward.

What are the 4 organ systems in the earthworm?

Annelids are segmented worms such as earthworms and leeches. Annelids have a coelom, closed circulatory system, excretory system, and complete digestive system.

What are the 5 characteristics of earthworm?

Earthworm Phylum Characteristics

• 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.

Do earthworms have 5 hearts?

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.

How many body parts does an earthworm have?

1 Answer. Worms have 5 parts in their body.

What is the structure of segmented worms?

Segmented worms are bilaterally symmetrical. Their body consists of a head region, a tail region, and a middle region of numerous repeated segments. Each segment is separate from the others by a structure called septa. Each segment contains a complete set of organs.

What structures help an earthworm move through the soil and where are they located?

The underside of the earthworm has bristles called setae that help the earthworm move. Label the setae on Figure 2. Internally, septa, or dividing walls, are located between the segments.

What are the seven body parts of a worm?

What Are the Seven Organ Systems of the Earthworm?

• Respiratory System. Earthworms don’t have lungs like mammals do.
• Circulatory System. An earthworm has a closed circulatory system that uses vessels to send blood through its body.
• Muscular System.
• Digestive System.
• Excretory System.
• Nervous System.
• Reproductive System.

How many organs do earthworms have?

They have five paired organs that act like hearts to pump their blood through large blood vessels. They have a brain and nerve cord. They have reproductive organs and waste-removal organs. Well-developed muscles let the worms crawl through the soil or on top of the ground.

What are the features of a worm?

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 external features of earthworms?

Externally, a thin non-cellular cuticle covers the body wall of the earthworm. Underneath this cuticle, a layer of the epidermis, followed by two muscle layers and coelomic epithelium (inner layer) is sheathed. The epithelium consists of a single layer of glandular columnar epithelium.

Why do earthworms have 5 hearts?

They have no heart with chambers, just five pairs of aortic arches that extend through the length of their bodies. These five pairs of aortic arches can be called five hearts even though they do not fit the general definition of a heart since that includes one organ having multiple chambers, and an arch has none.

What type of body cavity Do earthworms have?

coelom
There is a large cavity of earthworms called the coelom, which extends across the whole length of the body. The cavity is formed by the division of the embryonic mesoderm.

Does an earthworm have a jaw?

Both worms have protein-rich jaws, but the clam worm’s jaws contain just zinc while the bloodworm’s jaws contain zinc and copper.

What are the structural adaptations of an earthworm?

Structural adaptations Each segment on an earthworm’s body has a number of bristly hairs, called setae (sometimes written as chaetae). These hairs provide some grip to help the earthworm move through the soil. An earthworm has a streamlined body with no antennae or fins or arms or legs!

What structures help earthworms form cocoons?

Adult (sexually mature) earthworms have a distinct swelling called a clitellum. It is located about one-third of the way down the earthworm. The clitellum is often white or orange in colour. It produces most of the material secreted to form earthworm cocoons.

Which two types of structures make up the earthworms heart?

The heart-like structures in the earthworm are called aortic arches, which pump blood out into the network of vessels that run in a circuit through the body. The aortic arches sit near the head of the worm and encircle the esophagus, the tube through which food passes on its way to the gut.