Annelida Flashcards
What is the literal name of Annelida?
(Remember they are segmented)
Annelus (latin)
“Little Ring”
How have annelida evolved throughout the years?
(8 advancements)
- Have a true segmented body
- True coelom
- Circulatory system (Pumping heart; 5 hearts).
- Respiratory system (respiratory pigments).
- Bilateral symmetry
- Triploblastic
- complete digestive tract (mouth and anus)
- Nervous and excretory system.
What are the segments called in Annelida and arthropods?
(RStarts with Meta)
Metameres
Segments have external circular rings called?
Annuli
What are the internal segmentats called?
Septa
What is the process in which the body is divided into a series of segments?
Metamerism
(Occurs in Arthropods as well).
Each segments have all major organ system : circulatory, nervous and excretory.
(true or false_
True
What does metamerism do the the body of the annelida?
Repeat many organs along the body length.
When the body wall muscles is divided what is the termed used for it?
Muscle Block
What are the advantages of segmentation?
(3 advantages)
- If a segment is injured , other segment can still function.
- A more sophisticated nervous system.
- Independent movement of separate segments.
How many muscle layers do they have?
2 muscle layers.
What are the names of the 2 muscle layers found in Annelida?
Outer circular & Inner longitudinal muscle layers.
All annelids have tiny pairs of chitinous britsles called setae.
(True or false?)
False. Hirudinida (leeches) do not have these setae.
What is the purpose of the setae?
Aid in anchorage, and helps firmly grip the medium through they travel/
Annelid body have a thin outer layer of cuticle surrounding the epidermis.
(True or false)
True.
What is the function of the Epithelium?
It secrets outer transparent moist cuticle.
Describe the coelom found in Annelida.
(DIVIDED.)
- It is well-developed.
- Divided into compartments by septa.
What is the function of the septa in the Annelida?
It is a cross wall that prevents fluids from shifting from one body region to another.
What is the function of the Coalomic Fluid?
(what type of skeleton?).
Hydrostatic skeleton.
What are the specialised respiratory structures?
Gillsa and Parapodia.
Open or closed circulatory system?
Closed circulatory system.
What are the main features included in the closed circulatory system of annelida?
- Blood vessels.
- dorsal and ventral longitudinal vessels
- Aortic arches (heart). Pumps blood segmentally arranged.
Respiratory pigments are found where?
In the coelom fluid and blood cells.
Where do Annelida live?
(Habitat)
Moist terrestrial soils, freshwater and warine.
What is the most family annelida?
Earthworms.
How many classes do annelida have?
2 main class and 2 main subclass.
Polchaeta, clitellata (oligochaeta and Hirudinida) describe them.
(hair and habitat distinction)
Polychaeta- have many long hairs and are marine worms.
Oligochaeta- have few long hairs and are terrestrial soil worms.
Hirudinida- Have no hairs, and live in freshwater.
What is the typical range of size of the annelida?
12 to 30 cm
What is the diet of oligochaetes
feed on;Decaying organic matter, leaves and vegetation, animal matter.
Circulation and respiration of annelida.
- Can diffused across body wall through moist skin.
- Blood flowing through the body wall also exchanges respiratory gases with the atmosphere.
- Some have gills and lungs to aid in respiration.
- Blood have O2 and pigments of haemoglobin dissolved in plasma.
- Oxygen combinded with respiratory pigments dissolve in plasma.
NAME the double transport system in Annelids.
- COelomic fluid
- A closoed circulatory system.
What does a closed circulatory system mean?
Blood flows continually within vessels and capillaries.
What is the function of the dorsal vessel in the circulatory system of annelids?
The dorsal vessels recieve blood from the blood wall and digestive tract, which then pumps it anteriorly into 5 pairs of heart.
What is the purpose of ventral vessel in the Annelida?
The heart pumps blood tot he ventral vessel then it is distributed to the brain and the rest of the body.
What is the function of the aortic arches?
To maintain steady pressure of blood in the ventrla vessels
How many hearts does the oligochaeta worm have?
(10 or 5)
10 hearts total.
or 5 pairs.
