In the first unit of Biology 11 we had learned the evolution theory, which can be summarized as all animals have a common ancestor and the early animals populated seas, fresh waters, and eventually land.
In unit 9, I get familiar with sponges, which are animals of the phylum Porifera and animals of phylum Cnidaria. Cnidarians can be classified as having two layers of tissue, outer epidermis and inner endodermis (gastrodermis), with jelly-like mesoglea in between. It has no coelom and contains only one opening for both mouth and anus. When sessile, Cnidarians are refereed to as “polyp” and when motile or free swimming, they are refereed to as “medusa.” Moreover, Cnidarians can live in either marine or freshwater and can reproduce sexually and asexually.
Sponges are also very important in biology as they are a diverse group consisting of all species of sponges of about 5,000 total. They are sessile, obtain food by filter and have no specific type of symmetry and no body cavity organization.
Examples of cnidarians are jelly fish, coral and sea anemones. Examples of Porifera include Asconoid sea sponges and clouds sponges or Clathrina clathrus. Below are two specific images of phylum Cnidaria, a jellyfish, and phylum Porifera (sponges) :
Assignments:
In the “How do sponges, cnidarians, flatworms, and roundworms obtain food Virtual Lab,” assignment, I learned about the four main types of feeders, which are:
- parasites (obtain food from the host)
- filter feeders (filter bacteria, algae and other materials from the water in which they live in)
- predators (hunt and kill prey food)
- scavengers (feed on remains of dead organisms)
For the “Virtual Dive” assignment, I created a very complex and elaborate journal explaining and analyzing species such as Red Beard Sponge, Azure Vase Sponge, Colourful Sea Whip and CannonBall Jellyfish.
Porifera and Cnidaria Comparison
Below is my Prezi Presentation comparing and contrasting Porifera and Cnidaria.
https://prezi.com/mche28wi3uvi/porifera-and-cnidaria-comparison/
Correct answers of questions I had trouble with on the Unit 9 Exam:
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In the jellyfish, the medusoid stage predominates
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Concentration of nerves at the anterior end of organism: cephalization
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Coelom is advantageous: it allows room for the development of internal organs
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Animals range from unspecialized single-celled to specialized multicellular forms is not a charcateristuc of all animal
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From primitive to advanced: multicellularity, bilateral symmetry, acoelomate, pseudocoelomate, coelomate
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Sponge cells which begin the digestion of food are collar cells and consist of many cells rather than one large cell because it is easier for food and oxygen to diffuse into many cells rather than one large one
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Sponges are derived from protozoans; the other invertebrate groups independently derived from other protozoans.
Reference:
Image 1: http://phylumskeletalsystem.weebly.com/cnidaria.html
Image 2: http://smithsworldofscience.weebly.com/phylum-porifera.html
Featured image: http://unit10animalevolution.wikispaces.com/porifera
Biology 11 