ncarbone's blog

Sharks and some other marine organisms are able to use electric signals to their advantage. Some organisms can emit electrical signals while others are highly sensitive to electrical signals. Sharks specifically are highly sensitive to electrical signals that can be used for communication and detection of the environment. Organisms that emit electrical signals can use their abilities for defense or killing prey as well. There are two main types of electrical receptors. The first being tuberous receptors which are found only in electric fish and respond to the high frequency discharge rates. The other type of electrical receptors is ampullary receptors. These receptors are found in both electric and non-electric fish and respond to much lower frequencies.

Organisms use vibration and sound perception sensory systems to help them respond to their environment. Snakes posses two sensory systems to respond to both airborne and substrate vibrations. Squid and Cuttlefish have a line of ciliated cells on their heads and tentacles that area analogues of lateral lines in fish. Water striders use water disturbance for sex determination. Males and females have different wave signals that they create. Pit vipers have pit organ neurons that overlap in their brain with visual neurons. This produces an infrared vision that allows them to detect prey.

Organisms have different specialized sensory systems. Many organisms are highly sensitive to small amounts of chemical substances. Many fish are highly sensitive to amino acids found in many marine mammals. Many fish are highly sensitive to amino acids. Taste buds are another sensory system that organisms have. Catfish have taste buds throughout their body and are essentially open pores with microvilli for increased surface area. Insects are hypothesized to have five different sensory neurons, each with a different purpose.

Organisms respond to an array of different environmental stimuli. Most responses to stimuli occur through the presence of accessory structures such as ears, nose, and eyes. Within each of these larger sensory structures are sensory neurons. Information is detected though these structures in three different ways. The first way is the sense organ can be directional as it gives different signals if turned toward or away from the source of the stimulus. The second way is when signals are obtained from a pair of similar sense organs and are compared. An example of this is hearing via two different ears. The third way is signals can be compared together in time and space.

It was determined that unknown #6 is 2-hexanone. The reaction with 2,4-Dinitrophenylhydrazine was a positive test confirming that the compound was either a ketone or and aldehyde and not an alcohol. The Schiff’s test showed a light pink color meaning it was a negative test determining that the compound was a ketone and not an aldehyde. The iodoform test showed that the compound was water soluble and formed a yellow precipitate confirming the compound to be a methyl ketone. The melting point of the compound was found to be at 111-112°C which is comparable to the melting point of 2-hexanone (110°C). 5-phenoxy-2-pentanone also has a comparable melting point of 110°C, but after observing the H-NMR spectrum of the two compounds it showed that unknown #6 was 2-hexanone. This is due to the peaks visible at 2.5-2.0 ppm and the peaks at 0.5-1.5 ppm. 5-phenoxy-2-pentanone shows peaks further downfield due to the presence of a double bonded oxygen and an oxygen bonded to a benzene ring.

We conducted a survey for students at UMass Amherst to collect their thoughts about how gene editing should be used and regulated in the medical field pertaining to the ethics. Survey options consisted of 4 options: strongly agree, somewhat agree, somewhat disagree, and strongly disagree. We used a Likert-scale for the data to be easily analyzed via a median or mode and displayed in a bar graph. It is the most widely used approach in survey research. A survey pertaining to 3 different scenarios regarding germline gene editing was sent out to 40 UMass students. Each scenario included 3 survey questions. We analyzed how students believe gene editing should be controlled and therefore what regulations need to be executed. Visual representations of data from surveys demonstrated these conclusions. The data collected regarding the ethics of the 3 scenarios will be pooled together as a consensus overview of germline gene editing and displayed via a pie chart.

Modern gene editing tools have the potential to treat diseases from a new perspective. A commonly popular technique used frequently to achieve gene editing is a CRISPR-Cas9 protein complex. With the use of CRISPR-Cas9, specific genes are targeted and the DNA sequence is then modified. Researchers are currently practicing gene editing in various subjects and performing the techniques in experimental research. On the other hand, scientists are delaying the use of gene editing for safety concerns and regulations. For our project, we will be discussing the ethics and various applications of germline gene editing. Germline editing changes the human embryo genome at an early stage. Germline editing also can have an affect on every cell including sperm and egg cells and also may potentially be passed onto future generations.

Hummingbirds have also adapted for flight. In order to fly they must generate enough lift. Generating more lift requires either increasing the velocity of the wings movement or increasing the wing area. However, in study looking at the correlation between wing size and metabolic rate the wing size relative to body size did not correlate with metabolic rate during hovering. Overall hummingbirds may not reduce metabolic expenditure by manipulating wing size.  

Hummingbirds have adapted their digestive system in order to sufficiently support their high caloric intake. They use their newly ingested sugars as a fuel for flight. They are able to quickly digest sugars for immediate use. It takes a hummingbird about 40 minutes to turn food into fuel whereas it can take a human up to 40 hours to digest. This is partly due to their small digestive tracks and the absorption of nutrients across the intestine. They also have a high capacity for paracellular and transcellular movement of glucose.

Hummingbirds have a high daily energy requirement for their size compared to other organisms including humans. The average sized human requires 2,000-2,500 kcal/day whereas a 3.5kg hummingbird requires 7.65kcal/day. If humans needed the same average intake as hummingbirds it would require about 800 can of coke in a day to meet the caloric requirements. Hummingbirds have high metabolic rates and various adaptions to make this work. They have a sufficient oxygen delivery system to tissues, rapid conversion of oxygen and nutrients to ATP, a high capacity to transport stored nutrients to fuel, and a digestive capacity to supply uptake of nutrients at sufficient rates. Hummingbirds muscle morphology is also highly adapted to suit their lifestyles. They have high capillary density to support high rates of oxygen delivery along with a high mitochondrial density.