Confocal Microscopy Lab
Confocal microscopy uses a laser that produces excitation light. This laser light reflects off of a dichroic mirror and then the laser light hits two mirrors that are mounted on motors. The mirrors then scan the laser light across the sample. Dye that is found in the sample then fluoresces (Weeks, 2003). Filamin was labeled with a red fluorescent label rhodamine (TRITC) and actin was labeled with the green fluorescent label fluoroscein (FITC) which was conjugated to the actin-binding fungal toxin phalloidin. The emitted light from the dyes passes back through the mirrors and passes through the dichroic mirror and is focuses into a pinhole. With confocal microscopy, a complete image of the sample is never seen. Only one point of the sample can be observed at a time. The amount of light that passes back through is detected by the microscope (Ladic, 1995). The intensity of the red light seen is proportional to the amount of filamin present and the intensity of the green light seen is proportional to the amount of actin present in the sample of Drosophila melanogaster ovaries.
Confocal microscopy is able to produce images that are very free from interference. The confocal pinhole allows the microscope to reject out of focus fluorescent light (Weeks, 2003). This means that the image comes from a thin section of the ovary sample. Many thin sections will be scanned through the sample; this allows a clean three dimensional image to be made. A confocal microscope has a few advantages over regular optical microscopes. Confocal microscopes have controllable depth of field, the elimination of image degrading information that is out of focus, and the ability to collect series of data from s...
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Okonkwo is known throughout Umuofia to be extremely masculine. He rarely shows signs of fear or weakness. This is because Oknokwo promised himself he would be the complete opposite of his father Unoka. Unoka had passed away ten years prior to when the story takes place but he has always been remembered as a weak, lazy, poor man who could barely provide for his family. He was always in debt and didn't care to work, he would play his flute all day everyday if he was able to. "People laughed at him because he was a loafer, and they swore never to lend him any more money because he never paid back" (5). Unoka was the laugh of the town and Okonkwo would never allow himself be that.
Robert Warren, Lisa Nagy, Jane Selegue, Julie Gates, and Sean Carroll produced this experiment that wanted to examine homeotic gene expression in butterflies. The hypothesis they tested was do homeotic genes have driven morphological change or do the homeotic genes provide a pre-existing plan where insects segment diversity evolved. The genes Antp, Scr, Abd-A, and Ubx were isolated from a cDNA library and were used to explore differences in limb and wing numbers between flies and butterflies. Where Ubx and Abd-A are expressed, the limb and wing numbers arose. They started to wonder if the expression of BX-C genes were different in butterflies (P.Coeni) and fruit flies (drosophila). When they did tests, they saw that conservation of BX-C and ANT-C homeotic gene expression are fundamentally similar and don’t explain the differences in appendages in each species. They looked into embryogenesis, and at 20% of the embryogenesis of butterflies, they saw Abd-A protein and RNA are expressed in the anterior and abdominal segments. High levels of Antp expression are seen in the thorax. Past the 20% mark of embryogenesis, the patterns seen of Abd-A, DII, and Antp expression differed extremely - no DII or Antp were expressed in the abdominal proleg.
In Drosophila, there are eight hox genes, which are generally divided up into two complexes, the antennapedia and bithorax. The antennapedia complex contains genes responsible for coding for the head and thorax regions of the body and begins at the 3’ end of the DNA sequence making up the homeotic gene cluster. On the other hand, the bithorax complex codes for the abdominal region of the body and is located at the 5’ end of the DNA sequence. While the pair-rule and segment polarity genes are the ones that establish the segments along the body of the fly embryo, it is the homeotic genes that then assist in determining the identities of each specific segment. This ultimately leads to a distinct anterior-posterior polarity along the ...
...s in these target organs at critical developmental periods would result in defects of these organs (5).
The objective of this experiment is to determine what genes are responsible for the white-eye color in two strains of Drosophila melanogaster, known as the common fruit fly. Drosophila is used as the experimental organism for many reasons which include its small size, easy maintenance, short 10 day generation time, and a fully sequenced genome. The characteristics of the wild type, which is the most common phenotype found in nature, include brick red eyes, long wings, gray/tan body, and smooth bristles. Of course, there are mutations that occur that cause specific traits to deviate from the wild-type phenotype. These traits include wing length, bristle shape, body color, and eye color.
At the beginning of the novel Okonkwo was a fairly wealthy and well-respected member of the Igbo society, but it had not always been that way for him. Okonkwo?s father, Unoka, had been a lazy man who would rather play his flute than take care of his crops. Unoka was said to be a charming man, and was able to borrow large amounts of money from his friends, but was never able to pay it back. As a result, Okonkwo has grown up very poor and ashamed of his lazy father. At one point in the book, Okonkwo remembers hearing one of his playmates calling his father an ?agbala,? which was the word for woman, but all described a man who had taken not titles (13). Okonkwo never forgets this, and actually develops a deep-seated fear that people will think that he is weak like his father. As I mentioned, Okonkwo became very well known, and his wealth and prestige rested solely on his own personal achievements. Okonkwo had received no inheritance from his poor father, no land and no money. As a young man, Okonkwo had been very successful wrestler, and as he grew older he became a well-known warrior. He was said to have brought home five human heads, which was a great achievement even for men who were much older that he was. At the beginning of the story, Okonkwo had obtained two titles, and had the respect of every man from all nine villages of Umuofia. Symbols of his wealth and prestige were his family and his compound. As I mentioned earlier, Okonwo had received no inheritance, and at the time of this story Okonkwo is still fairly young, and the fact that he had three wives, several children, and a very productive piece of land showed that Okonkwo was a very diligent worker. ?Okonkwo ruled his household with a heavy hand. His wives, especially...
One can almost feel the searing penetration of Lewis Thomas’ analytical eye as it descends the narrow barrel of the microscope and explodes onto a scene of vigorous, animated, interactive little cells—cells inescapably engrossed in relaying messages to one another with every bump and bounce; with every brush of the elbow, lick of the stamp, and click of the mouse…
In these few chapters that we read, we have already learned a lot about Okonkwo, his life, and how he shows sympathy to some, but to others he is heartless. Okonkwo is other wise known as an unsympathetic person. Okonkwo is a clan leader of umuofia who holds many titles and is well known among his people. Okonkwo's daily life consists of tending to the three yam farms he has produced and to make numerous offerings to numerous gods and to help himself and his family. Okonkwo's personality is hard driven, since his father did not provide for him and his family Okonkwo had to start man hood early and this led him to be very successful in his adulthood, Okonkwo is an unsympathetic character who only shows sympathy rarely because he believes it's a sign of weakness Okonkwo's family relationships make him a sympathetic character because when his children show signs of manliness or do their jobs right he shows sympathy towards them. He is an unsympathetic character because whenever he get a little mad he has to take his anger out on something and that is usually vented by beating his wife's.
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%.
Okonkwo is “a man of action, a man of war” (7) and a member of high status in the Igbo village. He holds the prominent position of village clansman due to the fact that he had “shown incredible prowess in two intertribal wars” (5). Okonkwo’s hard work had made him a “wealthy farmer” (5) and a recognized individual amongst the nine villages of Umuofia and beyond. Okonkwo’s tragic flaw isn’t that he was afraid of work, but rather his fear of weakness and failure which stems from his father’s, Unoka, unproductive life and disgraceful death. “Perhaps down in his heart Okonkwo was not a cruel man. But his whole life was dominated by fear, the fear of failure and weakness….It was not external but lay deep within himself. It was the fear of himself, lest he should be found to resemble his father.” Okonkwo’s father was a lazy, carefree man whom had a reputation of being “poor and his wife and children had just barely enough to eat... they swore never to lend him any more money because he never paid back.” (5) Unoka had never taught Okonkwo what was right and wrong, and as a result Okonkwo had to interpret how to be a “good man”. Okonkwo’s self-interpretation leads him to conclude that a “good man” was someone who was the exact opposite of his father and therefore anything that his father did was weak and unnecessary.
The principle behind the refractive telescopes is the use of two glass lenses (objective lens and eyepiece lens) to gather and bend parallel light rays in a certain way so that the image fits the size of the eye's pupil. Light rays is gather through the opening of the telescope called the aperture and passes through the objective lens and refracts onto a single point called the focal point. From there the light rays continue the same direction until it hits the eyepiece lens which also refract the light back into parallel rays. During the process, the image that enters our eyes is actually reverse of the original image and magnified because the size in which we preceive the image.
...ecial cells, the queen puts the eggs from which a new queen will emerge. After the larvae develop from the eggs, the cells are covered with wax.
Unoka – Okonkwo’s father, Unoka, was considered lazy and a failure. He never worked and always took from others. Okonkwo considered him a complete embarrassment and vowed never to be like his father. He had to hate what Unoka once loved, and never borrow money or stop working.
Because cells are the ‘basic unit of life’, the study of cells, cytology, can be considered one of the most important areas of biological research. Almost every day on the evening news, we are told about new discoveries in cell biology, such as cancer research, cloning, and embryology. (https://highered.mheducation.com/sites/0073031216/student_view0/exercise3/the_importance_of_cell_biology.html) This report provides an insight into the differences in the structure of cells and the way that they carry out their internal mechanisms. Cells form the basis of all living things and they are the smallest single unit of life.