- What is Placodus gigas?
- Where did Placodus live?
- How did Placodus adapt to its environment?
- Was Placodus a swimmer?
- What is the scientific name of Placodus?
- Are Paraplacodus and Placodus “Triassic sea cows”?
- What does placodon stand for?
- Where are Placodus fossils found?
- What is Placodus in biology?
- What is the central nervous system like in reptiles?
- What is the central nervous system in vertebrates?
- What are the three divisions of the vertebrate nervous system?
- What is the nervous system like in amphibians?
- What is the function of the vertebrate nervous system?
- What are the components of the nervous system?
- What is the circulatory system of amphibians?
- How does the nervous system work in mammals?
- What are the parts of the vertebrate nervous system?
- What is the structure of the cerebral cortex in reptiles?
- What is the blood cycle like in amphibians?
- How are circulatory systems of animals like amphibians different?
What is Placodus gigas?
Placodus is known from two valid species in the Germanic Basin: Placodus gigas and Placodus antiquior. Placodus gigas Agassiz, 1833 was first identified two hundred years ago in the Germanic Triassic “Muschelkalk,” as a “large Triassic fish” ( Muenster, 1830; Fig. 1) which was named by Agassiz (1833).
Where did Placodus live?
Placodus (meaning ‘flat tooth’) was a genus of marine reptiles belonging to the order Placodontia, which swam in the shallow seas of the middle Triassic period (c. 240 million years ago). Fossils of Placodus have been found in Central Europe (Germany, France, Poland) and China.
How did Placodus adapt to its environment?
Placodus and its relatives were not as well-adapted to aquatic life as some later reptile groups, like the closely related plesiosaurs. Their flattened tails and short legs, which probably ended in webbed feet, would have been their main means of propulsion in the water.
Was Placodus a swimmer?
For a long time Placoduswas thought to be an exclusively European genus, but the naming of the second species, P. inexpectatus, in China in 2008 shows that while Placoduswas not a strong ocean going swimmer, it was perfectly capable of following Triassic coastlines to colonise new parts of the globe. Further reading
What is the scientific name of Placodus?
Placodus Name:Placodus(Flat tooth). Phonetic:Plak-oh-dus. Named By:Louis Agassiz - 1833. Classification:Chordata, Reptilia, Sauropterygia, Placodontia. Species:P. gigas (type), P. inexpectatus.
Are Paraplacodus and Placodus “Triassic sea cows”?
The main arguments in favour of classifying Paraplacodus, Placodus and Cyamodus as “Triassic sea cows” and herbivorous macroalgae feeders are their anatomical and osteological similarities to the modern Steller’s sea cow and to Tertiary sirenians.
What does placodon stand for?
Placodus (meaning ‘flat tooth’) was a genus of marine reptiles, belonging to the order Placodontia, which swam in the shallow seas of the middle Triassic period (c. 240 million years ago). Fossils of Placodus have been found in Central Europe (Germany, France, Poland) and China.
Where are Placodus fossils found?
Fossils of Placodus have been found in Central Europe ( Germany, France, Poland) and China . Placodus had a stocky body with a long tail, and reached a total length of up to 2 metres (6.6 ft). It had a short neck, and a heavy skull. They were specialized for a durophagous diet of shellfish, such as bivalves.
What is Placodus in biology?
Placodus. Placodus (meaning ‘flat tooth’) was a genus of marine reptiles, belonging to the order Placodontia, which swam in the shallow seas of the middle Triassic period (c. 240 million years ago). Fossils of Placodus have been found in Central Europe ( Germany, France, Poland) and China .
What is the central nervous system like in reptiles?
Central nervous system is better developed in reptiles than amphibians. The cerebral hemispheres are enlarged by the presence of a mass of gray matter, the corpus striatum. Cerebral cortex is not developed in reptiles. 7. Twelve pairs of cranial nerves are present (except snakes).
What is the central nervous system in vertebrates?
Nervous System. If the eyes are primarily off to the side then they are considered prey. Fish, amphibians, reptiles, birds and mammals all have a brain and a spinal cord which make up the central nervous system of all vertebrates and allow them to have more complex interactions with the environment than most invertebrates.
What are the three divisions of the vertebrate nervous system?
The vertebrate nervous system has three divisions: (i) A central nervous system comprising the brain and spinal cord. Its function is to receive the stimulus from the receptors and transmit its response to the effectors. Thus, it coordinates all the functions of the body.
What is the nervous system like in amphibians?
The nervous system is basically the same as in other vertebrates, with a central brain, a spinal cord, and nerves throughout the body.The amphibian brain is less developed compared to that of reptiles, birds, and mammals. It consists of a cerebrum, midbrain, and cerebellum of similar sizes.
What is the function of the vertebrate nervous system?
The cells, tissues, and organs of the vertebrate nervous system collectively coordinate the body and allow an organism to sense and respond to stimuli. The vertebrate nervous system includes the brain, brainstem, spinal cord, cranial and peripheral nerves, and ganglia.
What are the components of the nervous system?
With regard to the vertebrates, the nervous system ( Fig. 1) consists of the brain, brainstem, spinal cord, cranial and peripheral nerves, and ganglia. The brain and spinal cord together comprise the central nervous system, whereas the nerves and ganglia that leave the brain and spinal cord constitute the peripheral nervous system.
What is the circulatory system of amphibians?
For the blood circulation, amphibians have three-chambered heart, i.e. two atria and one ventricle in their circulatory system. Their nervous system consists of a central brain, spinal cord and nerves with a less developed brain. For the excretion, amphibians have two kidneys which primarily excrete uric acid from the cloacal vent.
How does the nervous system work in mammals?
Every mammal uses their nervous system to regulate basic things such as their heartbeat, and involuntary contractions and relaxations. Humans, as mammals, have the highest brain to body size ratio, meaning that they can have very complex interactions with the environment.
What are the parts of the vertebrate nervous system?
The vertebrate nervous system includes the brain, brainstem, spinal cord, cranial and peripheral nerves, and ganglia. The vertebrate brain consists of three basic divisions: prosencephalon, mesencephalon, and rhombencephalon.
What is the structure of the cerebral cortex in reptiles?
… The cerebral cortex in reptiles comprises a layered structure in the superficial area and this cortical layer is divided into the following regions: medial, dorsomedial, dorsal (generally considered homologous to the mammalian isocortex), and lateral cortices (the mammalian piriform cortex) [1] [2] [3].
What is the blood cycle like in amphibians?
Then the cycle begins again. One aspect of the amphibian system is that the blood leaving the heart for the body is only partially aerated; part of it is made up of deoxygenated blood returned from the body.
How are circulatory systems of animals like amphibians different?
Circulatory systems of animals like amphibians differ in aspects like the number of circuits and heart chambers. Among vertebrates like reptiles, birds, mammals, and amphibians, the circulation of the blood takes place in two circuits. One circuit moves the blood through the lungs and then back to the heart.
