The Relationship Between Planarians And A Centralized Nervous System

1. Many experiments were conducted during the 1950s and 1960s with chick embryos and they showed that two patches of tissue essentially controlled the development of the pattern of bones inside limbs.  Describe at

Planarians are hermaphrodites and have both the male and female organs but they are reproduced by asexual reproduction – known as fission (Fernandez, 2016). They are commonly in freshwater streams and ponds (Collines, 2007). They are carnivorous, feeding on living and

In one of the experiments, Mary Gasseling took a little patch of tissue, early in development, from what would be the pinky side of a limb bud. She took that tissue and put it on the opposite side right beneath where the first finger would form. The chick would develop and form a wing; the new fingers were also copies of the normal set. Basically, the tissue (more specifically some molecule or gene inside the tissue) was able to direct the development of the pattern of the fingers. This led to further experiments that defined the ZPA, or the zone of polarizing activity. This patch of tissue is able to determine the difference between the pinky side and the thumb side.

Phylum: Chordata, an organism who developed a notched, a nervous system with that contain gill cleft with the vertebrates.

They must be eukaryotic, meaning they have nucleus, and in the domain Eukarya. In the Linnaean classification this could be in the kingdom Protista like a paramecium. Another Linnaean classification of this could be in kingdom Animalia, since they are heterotrophs and their cells contain a nucleus. They could be grouped as predators, since the organism is engulfing another organism. They could also be grouped based on their locomotion. They could have cilia, legs, or even flagella.

In the science world, Tetrahymena is a uni-cellular organism found in most fresh water ponds, streams and lakes. Tetrahymena cells can tolerate many environments and are notably used as a model organism in eukaryotic cell biology and research. A model organism can be defined as an organism that is easy to culture in a laboratory and shares many similar processes and genes with complex multi-cellular organisms, for example, cells in the human body. The use of Tetrahymena as a model organism has led to the discovery of ribozymes, telomere structure and even the motor protein, dynein.

It lacks a backbone, but has a nerve cord that runs down its back and a rod that runs the length of its body parallel to the nerve cord that supports the body (notochord). Humans have a notochord as an embryo, but it breaks up and becomes part of the disks that lie between our vertebrae. Also shared with Amphioxus are gill arches, the bar of cartilage associated with each arch and the cartilage that form jaws, ear bones and our voice box.

Dugesia tigrina are flatworms of the Turbellaria class that can live in saltwater or freshwater environments (Reddien and Alvarado 2004). These flatworms are also known as planaria and are notorious for their great ability of regeneration. The purpose of this experiment was to test if the regrowth of the planarian limbs was affected by light.

tissue regrow in the attachment site will be hard connective tissue. Don't forget about the rewiring of

The nervous system is a chain of interconnected nerve fibers which is constructed by the central nervous system and Peripheral nervous system. The job of the nervous system is to send messages from the brain and spinal cord to different parts of the body.

regrow legs in around four months, and some have been observed regrowing less vital parts of their

Your friend’s dog, Spot, jumped onto a table with a terrarium housing your pet salamander, Lizzie. Unfortunately, the table tipped over and Spot has suffered a head injury which damaged the primary motor cortex. Lizzie lost most of the distal right forelimb in the accident. Please answer the following questions regarding the nervous system and regeneration, in a .docx, .pptx, or .pdf format.

: In an observational study, the developmental stages of an axolotl’s embryo were observed and scientist were able to identify a series of changes in the gene expression that aided in understanding the axolotl’s regenerative abilities. The axolotl; also known as the Mexican salamander, is an amphibian related to the tiger salamander that is known for its ability to completely regenerate limbs and organs. Cellular regeneration is the regrowth of a damaged or missing organ part from the remaining tissue and that’s why this study is important to both the biological and medical communities. Through this study, biologist were able to identify what in the axolotl’s early development gives it its unique properties and how those genes are reactivated to trigger limb formation in an adult. Also, by studying the genes that allow for the axolotl to completely regenerate

The anatomical and functional divisions of the nervous system are divided into two categories the central nervous system (CNS) and the peripheral nervous system (PNS).

Planarians are flatworms and reproduce sexually. They are hermaphrodites and have the male and female reproduction organs. They exchange their sperm with other planarians to fertilize their eggs. When the eggs are fertilized, they are kept inside the planarian. In a couple months later, the eggs hatch and grow into adults. This helps the survival of specie because it makes a better genetic diversity among planarians. Planarians are able to reproduce asexual. One way they reproduce is by tail dropping. Tail dropping is when they separate into two different parts, to create a whole new copy. Another way to reproduce is called fragmentation. Fragmentation is like tail dropping, but split into many pieces. This makes it possible for them to regenerate,