Francia Pierre
Lab Report # 5
Regeneration and Reproduction of Planarian Flatworms
Abstract
The focus of this lab on planaria regeneration and development. Having been taught the gradient of morphogen and there were many experiments testing this possible phenomenon of regrowth. In a planarian there is a single adult stem cell type called the neoblast. Neoblast are abundantly present throughout the body and it divides continuously. This neoblast has the ability to regenerate different cell and organ types in the planarian, from the brain, digestive system, the sensory system to even the reproductive system. With this continuous stream of continuous division of cells it allows the cells of the planarian to be rapid in self-renewal of the entire
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Also there seemed to be extra planarian grown in all of the petri dishes even in the control petri dish.
Discussion
After the week our results we had unexpected results. As shown above in Figure 2 and 3, we had ended up with more planarian than expected. In Figure 3, which was the 2nd Planarian that we cut into three pieces there were about 4 different pieces that were shown. And even in the control group, which is Figure, we had more Planarian show up then we actually put in. After doing further research, there is a possible explanation to seeing more Planarians inside these petri dishes. The most realistic explanation is that the planarian that we had acquired were the type of planarian that did both asexual and sexual reproduction (Motonori et al. 2003). Since the cut planarian had grown, they had grown asexually but with the added planarian they would have been made sexually. The only other reason would be someone adding planarians to all of the petri dishes, but that is highly unlikely. So in conclusion our hypothesis that the identically cut planaria would re grow and be identical was supported by our
Planarians are free-living, carnivorous flatworms found in the Phylum Platyhelminthes, Class Turbellaria. Although the Phylum Platyhelminthes is known for having the animals with the most parasitic species, the class Turbellaria which consist of the Planaria, are a non-parasitic species. Platyhelminthes which translates to "flat worm" are triploblastic animals. This means that they have three tissue layers, the endoderm, mesoderm, and ectoderm. Planaria also are monoecious organisms, meaning that they have both female and male sex organs in one organism. Another characteristic of the Planaria is that they do not have a true body cavity, meaning that they are acoelomate organisms.
Planaria usually live in water, water doesn’t have any effect on them which the reason why it is used as a control group in this experiment. Planarian will be put near the edge in a two-chamber tray containing water, in the side that is not covered with a dark piece of paper. Five planaria will be tested in a 2- chamber tray. We will measure how long it takes the planaria to move from the edge of a chamber receiving light, to the dark chamber. Subsequently, start by adding the lower concentration of caffeine in the water, replacing planarian in the same position and measuring how long it takes now to go back to the dark chamber in the presence of caffeine. We will duplicate the same procedure with higher concentrations of caffeine and additionally take the average of the time all five planaria took to move from the edge of the chamber in brightness, to the dark chamber in different concentrations of
Oftentimes, people can recall at least one song they know that is undoubtedly catchy because of its repetitive nature. That song can become a nuisance, when it will not leave your mind. When a melody gets stuck in your head, sometimes it could take a whole day to forget the tune. A certain tune can be stuck in your brain for many years! In Oliver Sacks’ passage, “Brainworms, Sticky Music, and Catchy Tunes”, he talks about “earworms”, or a pathological repetition. Sacks uses patterns of development to inform the modern reader about the dark side of music.
The scientists were hoping for the cells to divide into 100 or so cells called blastocysts. They wanted to take these blastocysts and have them grow to replace nerve, muscle and other tissues. But only one of them came to the Six-cell stage and by then it stopped dividing. They had done a similar procedure they had eggs grow without sperm to fertilize, to develop parthenogenetically into blastocysts they think that using these to procedures together they could achieve human cloning.
Many seemingly unrelated factors might determine the ability of a specific tissue to regenerate into shoots and roots. Among them, mineral nutrients, plant growth regulators and environmental factors are critical. All ready standardized media for somatic embryogenesis and regeneration adopted to carry out regeneration round study. The medium consisted of macronutrients, micro nutrients, Fe-EDTA, vitamins, amino acids, sucrose/maltose, agar and plant growth regulators (auxins and cytokines). Coconut Water (CW) was used as organic additives in regeneration experiments. This was collected from tender nuts, filtered through Whatman filter paper (3 mm) and added in medium before autoclaving.
As I was anticipating writing this paper on American culture, I kept thinking of the culture that biologists grow in a petri dish. More specifically, the bacteria strep, which must be grown in a special medium called, blood agar. If someone has a "positive" culture, the bacteria strep has metabolized the blood in the agar and the petri dish will be clear. If someone has a "negative" culture, the petri dish will remain red.
Sordaria fimicola is a species of microscopic fungus that is an Ascomycete and are used to test for genetic variation in the lab setting (Sordaria fimicola: A Fungus used in Genetics, Volk). These organisms are what are called model organisms, or species that has been widely studied usually because it is easy to maintain and breed in a laboratory setting and has particular experimental advantages (Sordaria fimicola, Volk). S. fimicola, because it is in the Ascomycota phylum, have a distinguishing reproductive structure called the ascus, which is surrounded by the perithecium. This cylindrical sac-like structure houses 8 haploid spores; created through meiosis to produce 4 haploid spores and then mitosis to make 8 (Lab Manual, pg. 59-68). Based on the genotype they will vary in order and color. There are 3 different ratios that can arise from the 8 ascospores: 4:4, 2:2:2:2, and 2:4:2 (black/wild type and tan coloration). The 4:4 ratio suggests that no crossing over had occurred because there is no difference in order of the color parents that were mated. The two other ratios suggest genetic recombination, or crossing over, because of the
The cultures were maintained at 25±20C under 16 hr illumination of 4000 lux intensity. The results are presented in Table 1, it can be seen from the data that pH of the medium had significant effect not only on regeneration frequency but also on number of shoots developed in each culture. Maximum 62.5±4.7 percent cultures in CoS 98259 and 67.3±4.9 percent in CoS 767 developed shoots at pH 6.0 while regeneration frequency was the lowest at pH 5.6. An increase in pH form 6.0 to 6.2 and 6.4 reduced the frequency of shoot regeneration from the callus (Table
Heartworms are a parasitic nematode of mammals and have first been observed in Italy in 1626 (3). Later the parasite was introduced to the Americas by European immigrants leading to the earliest recorded heartworm finding in the United States in 1847 published in The Western Journal of Medicine and Surgery (3,5). In 1995 the intracellular Gram-negative bacterial endosymbiont Wolbachia, belonging to the order Rickettsiales, was identified to reside in the heartworms tissue (4).Today heartworm infections have been reported in all states except Alaska and the number of incidents are increasing at an alarming rate (5).
This paper analyzes whether or not gene to map distance in Sordaria fimicola is affected by changes in environmental conditions. The main focus is on how temperature affects the recombination frequency in this organism. It is analyzed if under different environmental conditions wt x gray and wt x tan varies in their percent crossing over. It is investigated how factors such as temperature and ultraviolet light have affected the gene to centromere distance in Sordaria. Results obtained in lab as well as scientific researches prove that as temperatures increases the percent of crossing over increases as well.
Regeneration is the process of restoration, renewal, and regrowth. Some things can regrow off the cut off of the old piece, according to Richard Johnson Goss, “By such regeneration whole organisms may dramatically replace substantial portions of themselves when they have been cut in two, or may grow organs or appendages that have been lost. Not all living things regenerate parts in this manner, however” (2016). Regeneration consists of new cells that are created by own cells. With this, stem cells divide to
The F2 punnett square shows that there should not be a female fly that has apterous wing mutation. Our observed experiment showed that female flies are capable of forming in the F2 Generation. Therefore, the mutation is located on autosomal chromosomes. In trial 1, the p value is not significant. This could be due to the fact that the male to female ratio in the F1 generation was unequal. In trial 2, the p value is significant and likely due to chance. The probability error is between 1 % and 5%.
The battle between sexual and asexual reproduction is a competition that has been ongoing for millions of years. Somewhere along the way due to its higher level of genetic variation, sexual reproduction was able to overcome the two fold advantage of asexual reproduction, and now dominates reproduction in organisms. However, some types of organisms such as worms and corals have acquired the ability to reproduce both sexually and asexually. The purpose of this paper is to explore the differences in asexual and sexual reproduction both from a biological and an evolutionary standpoint and to explain why evolution has made it possible for soft corals to reproduce both sexually and asexually.
c solution and sucked up some of the water in the cells. When we observed the cheek cells we found they were very different from the plant cells. The nucleus was in the middle of the cheek cells and there were a few cell organelles. The Planaria cell was all red and had lines running down it.