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Transcriptomes are the sum total of all the messenger RNA molecules expressed from the genome. Transcript/ gene isoforms are mRNAs that are produced from the same stretch of DNA but differ in stability and translational efficiency and potentially function since they have different transcription start sites, protein-coding DNA sequence, or UTRs. This paper goes into analysis of the drosophila transcriptome and proves that the drosophila genome is much more complex than previously imagined. This complexity arises from three sources: promoter, splice sites, polyadenylation sites.

Figure 4 looks into tissue- and sex-specific splicing in drosophila. Transcript diversity: over half of spliced genes encode two or more transcript isoforms. The researchers measured splicing efficiency through "per cent spliced in"- the fraction of isoforms that contain the particular exon. To examine the dynamics of splicing, switch scores are calculated for each splicing event, and examined tissue and sex-specific. Results show that most splicing events are highly tissue specific. Results also show that majority of the sex-specific splicing is due to tissue-specific splicing of tissues present specifically in either male flies (testes) or female flies (ovaries).

There are many possible ways to analyze DNA. Some popular methods include Gel Electrophoresis and Restriction Enzymes. The main purpose of Gel Electrophoresis is to separate DNA (genetic material) samples by size. The samples are attracted to the positive end of the well located on the gel, so they move in that direction. The smaller sized samples move much quicker than the large ones, making it easy to distinguish by size. The purpose of using restriction enzymes is to cut DNA at specific recognition sequences. The DNA is digested by some of the enzyme (for example EcoRI) and is fragmented into several sizes at specific sites. This allows for the fragments to be used in Gel Electrophoresis.

The task of finding a spider web on the UMass Campus was tricky. I had to look in weird, unbothered places to find a web. After days of keeping my eyes open, I found a spider web on the way from my class, on the side of the Lederle Graduate Research Center. I noticed that without light, the spider web was pretty hard to see. So to make the web visible in my photo, I took a picture with the flash on, several times, until the web was clearly visible in my photo. Then, I marked my exact location on my maps app (on my phone) to show exactly where I had found this spider web. 

Biologists in Africa’s Albertine Rift region recently made a surprising discovery – a new species of bird living high in the mountains of this incredibly biodiverse area. They named this bird Willard’s Sooty Boubou, which is closley related to another previously recognized high-elevation bird species, the Mountain Sooty Boubou. While these birds appear to be quite similar, the main difference between them is the elevations at which they are found. The Willard’s Sooty Boubou is found at approximately 1200-1900 meters, and the Mountain Sooty Boubou is found at 1800-3800 meters. Sadly, the discovery took an unexpected turn for the worse. While the team was quite happy to find this new bird, after analyzing its habitat they soon realized that more than half of it had been destroyed for agricultural needs. This has sparked debates in the local area on taking measures to protect the birds environment and conserve what is left of its habitat before it goes extinct. Estimates show that 50-70% of its habitat has been lost, and does not show signs of recovering without significant human intervention. By better understanding this new species of bird and identifying what kind of ecological niche it fills, scientists can learn how to better protect it in the face of growing threats.

• Embryos that have only one of the two sets of parental chromosomes = uniparental embryos
• Process to give embryos specific chromosomes from one parent only = uniparental disomy
  • Is this done to just investigate specific chromosomes? Or, are there natural processes where certain chromosomes from a set  get transferred and others don't? (seems unlikely)
• Previous research has shown that mammalian genes can function differently dependent upon whether they come from mother or father.
• Imprinted genes are expressed differently on paternal and maternal genes (first discovered, 1990s)
  • Methylation marks imprinted genes differently in egg and sperm

For in-vitro experiments, small fast-folding domains are most preferred as they are amenable to a great extent to observe the detailed physio-chemical behavior of R-groups and other primary, secondary, or tertiary interactions. However, small single domain proteins are very rare, and recent studies have suggested that the folding of domains in multi-domain proteins may not even be an independent process (if we look at the folding of domains as component of a larger protein). Thus, recent studies have tried to focus on in-vitro protein folding of larger proteins, and the results confirm the hypothesis that new complexities in folding landscape will emerge when multiple domains are interacting.

Biologists in Africa’s Albertine Rift region recently made a surprising discovery – a new species of bird living high in the mountains of this incredibly biodiverse area. They named this bird Willard’s Sooty Boubou, which is opposed to another previously recognized high-elevation species, the Mountain Sooty Boubou. These birds appear quite similar, but live at different elevations. Willard’s Sooty Boubou is found at approximately 1200-1900 meters, and the Mountain Sooty Boubou is found at 1800-3800 meters. While the team was quite happy to find this new bird, after analyzing its habitat they soon realized that more than half of it had been destroyed for agricultural needs. This has sparked debates in the local area on taking measures to protect the environment and conserve what is left of this birds habitat before it goes extinct. By better understanding this new species of bird and identifying what kind of ecological niche it fills, scientists can learn how to better protect it in the face of growing threats.

It’s important to test Lee for genetic disorder with non-cancerous cells because in cancerous cells, countless mutations have already taken place. If we use a cell with mutations, it is hard to determine the problem in the first place or which parent/gene the disease is inherited from. The DNA sequence may also be altered which coded for Lee’s condition. Going forward with non-cancerous cell, if we test the relevant parent/gene then we can find out the identity of the genetic disorder.

Jean Baptiste Lamarck was a French naturalist. He was the first to research invertebrate animals, and an early advocate for the idea of evolution. He had a discredited theory that evolution occurs when parent organisms pass on acquired traits to their offsprings. Now, we widely believe in Darwin's theory that evolution occurs because of natural selection.

However, new research findings suggest that Lamarck's theory might have some truth to it. We now know that hereditary epigenetic changes violate Mendelian principles. Epigenetic changes occur by transcriptional modifications: due to alterations on histone tail charges, chromatin binding, X-chromosome inactivations etc.  Although these changes pass on from mother to daughter cells, the modifications are typically erased in the germ cells. However, accumulating evidence suggests the opposite: passing on of epimutations. So far, the phenomenon has been spotted in plants, fruit flies and yeast.

However, scientists nowadays are starting to think that perhaps Lamarck's theory wasn't completely outrageous. The reason behind this phenomenon is because hereditary epigenetic changes seem to violate Mendelian principles. Epigenetic changes occur by transcriptional modifications due to alterations on histone tail charges, chromatin binding, X-chromosome inactivations etc.  Although these changes pass on from mother to daughter cells, normally the modifications are erased in the germ cells. Recently, however, accumulating evidence suggests the opposite: passing on of epimutations. The phenomenon "has been spotted in plants, fruit flies and yeast". There was also a major study in mammals that indicated towards epimutations heredity.