The Phylum Chordata
A Brief Overview
The Phylum Chordata is made up of the most evolved animals. The characteristics of chordates include bilateral symmetry, a segmented body, a ventral heart. The phylum contains all animals that, at some point in their lifetime had a stiffening rod, called a notochord. The phylum includes mammals, birds, reptiles, and amphibians. The circulatory system in animals in the phylum chordata is closed, with the heart containing no real wall. The whole structure is curved, and each end opens up into vessels which act as sinus channels. The circulatory system of Chordata is by far the most evolved of the nine phylums. Similar to Molluscs and Arthropods, Chordata have a closed circulatory system, and blood is pumped by a heart through cavities in the body. However, the circulatory system of most Chordata contains multiple chambered hearts, along with closed circulatory system, which is more evolved than any other chordates.
The Phylum Chordata is made up of the most evolved animals. The characteristics of chordates include bilateral symmetry, a segmented body, a ventral heart. The phylum contains all animals that, at some point in their lifetime had a stiffening rod, called a notochord. The phylum includes mammals, birds, reptiles, and amphibians. The circulatory system in animals in the phylum chordata is closed, with the heart containing no real wall. The whole structure is curved, and each end opens up into vessels which act as sinus channels. The circulatory system of Chordata is by far the most evolved of the nine phylums. Similar to Molluscs and Arthropods, Chordata have a closed circulatory system, and blood is pumped by a heart through cavities in the body. However, the circulatory system of most Chordata contains multiple chambered hearts, along with closed circulatory system, which is more evolved than any other chordates.
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Amphiprion ocellaris (Clownfish)
Amphiprion ocellaris have body and gill capillaries, as well as a two-chambered heart, which consists of an atrium, a thin sac like wall lining the heart. Amphiprion ocellaris, like many other species of fish, have an single looped, closed circulatory system. In amphiprion ocellaris the blood is pumed through the capillaries of the gills, and is sent to the capillaries within the blood tissues.
Amphiprion ocellaris have body and gill capillaries, as well as a two-chambered heart, which consists of an atrium, a thin sac like wall lining the heart. Amphiprion ocellaris, like many other species of fish, have an single looped, closed circulatory system. In amphiprion ocellaris the blood is pumed through the capillaries of the gills, and is sent to the capillaries within the blood tissues.
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Notophthalmus viridescens (Eastern Newt)
Notophthalmus viridescens have a closed circulatory system like other chordates. However, it is evolved from Amphiprion ocellaris due to the fact that it has a double circulatory system. This means that blood flows through two separate and distinct systems. Also, Notophtalmus viridescens shows evolution from Amphiprion ocellaris due to the fact that it has a triple chambered heart.
Notophthalmus viridescens have a closed circulatory system like other chordates. However, it is evolved from Amphiprion ocellaris due to the fact that it has a double circulatory system. This means that blood flows through two separate and distinct systems. Also, Notophtalmus viridescens shows evolution from Amphiprion ocellaris due to the fact that it has a triple chambered heart.
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Petroica phoenicea (Flame Robin)
Petroica phoenicea is also evolved from both Notophthalmus viridescens and Amphiprion ocellaris as their hearts are completely separated into two pumps for a total of four chambers, similar to that of mammals. The heart of Petroica phoenicea also consists of vessels that transport nutrients, oxygen, carbon dioxie, and waste. The blood is completley seperated intooxygenated and de-oxygenated blood.
Petroica phoenicea is also evolved from both Notophthalmus viridescens and Amphiprion ocellaris as their hearts are completely separated into two pumps for a total of four chambers, similar to that of mammals. The heart of Petroica phoenicea also consists of vessels that transport nutrients, oxygen, carbon dioxie, and waste. The blood is completley seperated intooxygenated and de-oxygenated blood.