What makes ascidians unique?
Many ascidians have a peculiar feature: they are able to accumulate vanadium. More primitive species tend to have higher levels of vanadium in their tissues.
What is the significance of a ascidian larva?
Furthermore, the ascidian larva represents an ideal model of early chordate development: it possesses the basic developmental and morphologic features of vertebrates but has the cellular and genomic simplicity of invertebrates.
How do you tell the difference between a sponge and a tunicate?
Sponges will often be soft, porous, and somewhat flexible, whereas most tunicates feel solid, firm, and gel-like (kind of like a gel-cushion you’d buy for your shoes). If you have ever accidentally stepped on a tunicate, you might have received a shot of water back, hence why they are often called “sea-squirts”.
Which of the following features are used to identify chordates?
In chordates, four common features appear at some point during development: a notochord, a dorsal hollow nerve cord, pharyngeal slits, and a post-anal tail.
What is the significance of ascidian tadpole?
This is because the ascidian tadpole larva is believed to represent the closest living form to the ancestral chordate; therefore, discovering the molecular mechanisms that underlie the development of this larva would facilitate our understanding of the ancestor of humans and other chordates.
Which type of metamorphosis is found in ascidian tadpole larva?
Complete answer: The ascidian tadpole larva undergoes a retrogressive metamorphosis. Retrogressive metamorphosis is a type of metamorphosis in which the free-swimming larva possessing advanced characteristics transforms into a sedentary adult with degenerative characteristics.
What type of metamorphosis is found in ascidian tadpole larva?
retrogressive metamorphosis
The ascidian tadpole larva undergoes a retrogressive metamorphosis. Retrogressive metamorphosis is a type of metamorphosis in which the free-swimming larva possessing advanced characteristics transforms into a sedentary adult with degenerative characteristics.
What are some characteristics of tunicates?
A tunicate is built like a barrel. The name, “tunicate” comes from the firm, but flexible body covering, called a tunic. Most tunicates live with the posterior, or lower end of the barrel attached firmly to a fixed object, and have two openings, or siphons, projecting from the other. Tunicates are plankton feeders.
Why is a tunicate not a sponge?
2 Whereas sponges lack organs and tissues, in their free-swimming larval stages tunicate bodies feature tails, pharyngeal gill slits, dorsal central nerve cords and notocords – structures found in animals with backbones. They have digestive tracts, hearts and circulatory systems that move pale green blood around.
Which of the following are key characteristics that appear at some stage during the development of a chordate?
Characteristics of Chordata. Animals in the phylum Chordata share five key chacteristics that appear at some stage during their development: a notochord, a dorsal hollow (tubular) nerve cord, pharyngeal gill arches or slits, a post-anal tail, and an endostyle/thyroid gland ((Figure)).
How do you identify an insect?
When you want to identify an insect the first step is to find out in which Order it is classified. For this you can use a dichotomous key. A dichotomous key is a tool that uses paired statements or questions to guide you to the solution.
How do you use key to identify insect orders?
Key to insect orders. When you want to identify an insect the first step is to find out in which Order it is classified. For this you can use a dichotomous key. A dichotomous key is a tool that uses paired statements or questions to guide you to the solution. To use the key it will be necessary to have a good hand lens and you should be familiar…
Where can I find information about the insect body structure?
The Key uses some specialised terms to describe specific parts of an insect’s body. An explanation of many of these terms can be found on the Insect body structure page or within the Insect fact files section.
Where can I find testing and identification services for insects?
In some cases, government agencies provide testing and identification services for specimens of insects and related arthropods. Below are two resources from the U.S. Department of Agriculture. You can also inquire with your local health department about such services in your area. Do You Need Pest Management Services?