Further evidence for the idea of evolution is the existence of vestigial structures. These vestiges are structures that are genetically determined but have lost some or all of their original function from the ancestral species. Oftentimes, vestigial structures are homologous to structures in related species. The way a vestige is formed is during typical evolutionary process when a structure loses its function and no longer provides a positive pressure. The loss of function can come from a change in the environment that the ancestral species originally adapted to. So long as the structure does not now present a negative pressure due to some hinderance on the species, it is considered neutral and not necessarily selected for or against. As a result, instead of losing the feature it may persist though it has no inherent value anymore. Common examples of vestigial structures are the hip bones that remain in snakes and whales. At a time, these species had ancestors that had limbs that required hips for mobility. Now that they no longer have the same limbs and are under different selective pressure, the genetics still encode for a hip bone, but it is not used. The bone is not a detractor and is not selected against but is slowly withering away over evolutionary time.
There are a variety of differences between my original multi-panel figure and the replicated figure. First of all, the photograph of the spider web seems to be taken from a different angle than the original. It is difficult to see the spider web in Figure A. I observed that the pencil in the replicated figures facing a different direction than the original. While the photograph for Figure B is pretty similar to the original figure, the replicated version is closer than the original photo. I also noticed that the editing of the figures is drastically different from the original. The sizing of Figure A and B in the replicated multi-panel figure are much thinner and taller than the ones in the original. Additionally, I observed that the letters A, B, and C are significantly larger than the boxes they are supposed to be in. While the white box for C is in the correct place, the boxes for A and B are placed in a different spot than the original boxes. The letters are also missing a period after them. Finally, I noticed that the sizing and placement of the black star is slightly different between the two multi-panel figures.
Adult african lungfish are obligate airbreathers. While they spend most of their time in shallow water, they must come up at least once an hour for air. When needed, the lungfish will pop its head above water and open its mouth. The hyoid arch of the fishs jaw will retract, opening the oropharyngeal cavity in the mouth. This creates a negative pressure, unlike what occurs with our own lungs, and allows fresh air to fill the cavity. Once full, the glottis opens, allowing passage to the lung. Air already in the lung will be expelled, passing over the fresh new air in the oropharygeal cavity. Unfortunately some old and new air mixes, so this process is not entirely efficient. Elastic recoil occurs as the lung deflates, causing the shape of the lungfish itself to deflate with it. The mouth of the lungfish will then close and its hyoid arch will return to its position, closing the oropharyngeal cavity. The fresh new air in this cavity will instead be directed to the lung, filling it. After this process, the lungfish is free to sit at the bottom of its shallow pool of water, gobbling up shrimp or other small organisms until it needs to breath again.
For centuries, biologists have been working to understand the basic functions of cells. These functions include reproduction, respiration, photosynthesis, endocytosis, metabolism, and a number of others. The unicellular organism Tetrahymena thermophila has offered biologists studying these processes a platform off of which to base their research. These cells have been used to make several groundbreaking scientific discoveries, such as the link between histone acetylation and gene regulation(Coyne, 2011). They have also been used to research and solve fundamental problems in the areas of molecular, cellular, and developmental biology(Coyne, 2011). Tetrahymena are ciliated protozoa that live in freshwater environments. These organisms are unique because they contain two nuclei despite being a single celled organism. One nucleus contains the somatic genome, and the other the germ line genome(Shieh). The diet of Tetrahymena is typically bacteria, however they will consume a number of different substances depending on their environment. Tetrahymena are incredibly complex organisms despite being single celled. They possess many of the qualities of multicellular organisms, such as nervous and digestive systems, and have about 25,000 genes(Shieh).
Upon comparing the two figure panels, multiple differences in the photographs became apparent. For the replicated figure B, the photograph shows more of the right side of the stair railing. The angle at which the stairs are photographed is slightly more straight-on than in the original photograph. This suggests that the picture was taken a different angle than the original image. Another observed difference is in the replicated figure C. The photograph shows a thumb, as well as more of the background behind the spiderweb. The UMass ID card also appears to be smaller in the replicated image. From this difference, it is inferred that the photograph was taken from farther away in the replicate photo, thus, showing part of the student’s hands and more of the background behind the spiderweb.
Multiple differences in the image lighting were observed between the two figure panels. In the replicated figure B, the tree and staircase has shadow lines and sunlight beams throughout the picture, whereas the original photo shows no shadows. Figure B is also has more vibrant, saturated colors throughout the photograph, unlike the original photo which looks more dull. The factor that is most likely creating these differences would be the time of day that these pictures were taken. The sun is highly noticeable in the replicated figure panel, whereas the sun in the original pictures looks less harsh. The weather also could be a factor affecting the picture quality, as the original pictures were taken on an overcast, cloudy day. The exposure of the lighting The replicated figure C, has a darker look to it. The tree in the background looks dark and shadowed, and the rest of the background to the right of the tree is extremely bright. This is most likely due to the camera exposure and focus.
Researchers find it really difficult to identify how emotions developed throughout evolution. It was initially theorized that emotions were learned throughout development, and they were not innate feelings. This means that once stimuli connected an experience with a feeling, they were paired together and created an emotion towards a specific situation. To test these theories, a 9-month old patient in a study was tasked with playing with different objects. These objects included fluffy animals, masks, dolls and more. The patient played with these animals and expressed no distinct or obvious emotion towards any specific object. This disconnect was called the neutral stimuli; the patient did not connect any object to a specific feeling. For the second round, the baby was exposed to a loud noise. As predicted, the loud noise startled the patient and they began to cry. This stimulus is unconditioned because the patient was not exposed to it before, but still was frightened by it. To tie the two together, now the patient was exposed to the same objects accompanied by a loud noise. When the baby reached out for one the objects that initially didn’t scare him, a loud noise would go off, and the baby would be frightened. This taught the baby to associate the loud scary noise with the harmless animal. This indicates how humans can learn emotion through association.
In terms of antidiabetic properties, metformin is typically used to combat type 2 diabetes mellitus. It is thought to decrease the hepatic (relating to the liver) production of glucose and increase the sensitivity to insulin as well as use of glucose by peripheral tissue. In addition metformin has been shown to successfully combat polycystic ovarian syndrome, which results in metabolic disorders due to the development of insulin resistance(Ikhlas, et al.). The anticancer properties of metformin were first discovered when researchers realized that cancer patients who were on metformin showed less mortality than other diabetic cancer patients on different drugs to deal with their diabetes (Ikhlas et al.). Mechanistically, metformin targets a number of important players in cancer pathway, but specifically the inhibition of mTORC1 via AMPK independent and AMPK dependant pathways.
Activated AMPK causes the p53 to become active. This then induces cell cycle arrest at G1/S phase, simultaneously upregulating pro-apoptotic genes including p21 and Bax. In addition Foxo3a, a tumor suppressor that affects genes including Bim, bNIP3, and Bcl-xLon are activated by AMPK as well. Furthermore, lipogenesis (acetyl CoA is converted to fatty acids) is inhibited (Ikhlas, et al.). AMPK finally leads to the inhibition of mTORC1, which is a huge player in proliferation and cell growth via its control of autophagy, translation of mRNA and metabolic effects (Ikhlas, et al.).
The very first thing I did to find out where to get my pictures, was look up where spiders like to make their webs. This led me to begin my search in my backyard which is the trees next to the mahar lecture hall, I looked in the volleyball court next to Newman center and the bulletin board by the entrance of mahar. I then looked in the trees and found a few webs and used a measuring tape to compare the size of each web. I then used the camera app on the iPhone to compare how each web looked in through the camera lens initially without any effects. This allowed me to select the best web for the assignment.
To get the two pictures I had to set some things up for a background and have a friend there. I first looked at the spider web through the camera lens and noticed the green grass was too light of a background so I had a friend hold up a dark purple folder behind the web. This allowed for the camera to pick up the web way better. I found the best angle to capture the web at, then I took pictures with the flash and no flash to find out which looked best and chose no flash as it did nothing. I then pulled the measuring tape to about one foot and held it perpendicular to the camera just below the web so the image shows the size of the web. I then snapped a few pictures. To get the picture of the setting I backed up about twenty feet and used the camera app to focus on the tree with the spider web then snapped a few pictures of the tree and its surroundings.
The next step was to edit the photos to allow for the best presentation of the pictures. I downloaded the free app Photoshop express onto my iPhone and uploaded the pictures to the app. I also at this time found a map of umass on the umass website. In the photoshop app I used the pen editing effect to draw a circle around the area I searched and put a dot/line on the area where the tree with the web is. I then clicked on the make collage choice and selected the three images. I arranged them to allow for the map to be displayed with the map key and for the picture of the web to include the ruler. I then downloaded the collage to my camera roll and emailed it to myself from my iPhone.
The rise of our cranium came in steps, starting with basic cartilage structures to eventually the hard bone we have today. First, a chondrocranium formed in cartilaginous fishes like lampreys. A chondrocranium is essentially a brain pan; a sheet of cartilage on which the brain and associated cranial nerves rest and branch out to the body. As can be expected, there was not much protection of the vital organs in these beings and that didn’t come until the formation of a dermatocranium. A dermatocranium was the first bony skull and is also referred to as a neurocranium. Early dermatocrania consisted of just six different bones known as the parietal, post-orbital, squamosal, quadrate, jugal, and quadratojugal. The fusion of these bones articulated with jaws, vertebrate, and other bony structures to protect the vital aspects of the central nervous system like the brain and the spinal cord. A third crania arose in fishes and it is referred to as a splanchnocranium. This is the bony (or cartilaginous depending on fish) structure that supports the gills and other thoracic structures. The splanchnocranium evolved into our axial skeleton over time and is now only prevalent in fishes and marine mammals.
The rise of our cranium came in steps. First, a chondrocranium formed in cartilaginous fishes like lampreys and hagfishes. A chondrocranium is essentially a brain pan; a sheet of cartilage on which the brain and associated cranial nerves rests and branches out throughout the body. As can be expected, there was not much protection of the vital organs in these being and that didn’t come until the formation of a dermatocranium. A dermatocranium was the first bony skull and is also referred to as a neurocranium. Early dermatocrania consisted of just six different bones known as the parietal, post-orbital, squamosal, quadrate, jugal, and quadratojugal. The fusion of these bones articulated with jaws, vertebrate, and other bony structures to protect the vital aspects of the central nervous system like the brain and the spinal cord. A third crania arose in fishes and it is referred to as a splanchnocranium. This is the bony (or cartilaginous depending on fish) structure that supports the gills and other thoracic structures. The splanchnocranium evolved into our axial skeleton over time and is now only prevalent in fishes and marine mammals.