Submitted by cslavin on Wed, 02/20/2019 - 15:32

A ECG is way to measue electrical signal in the heart. This measurement produces a PQRST graph. The P wave represents atrial depolarization by the SA node. The signal is then delayed, and atrial depolarization is complete before the QRS complex. At the QRS complex ventricle depolarization begins at the apex and atrial repolarization occurs. Following this, the ventricle depolarization completes. At the T wave, ventrical repolarization occurs. Then at the plataeu ventrical repolarization is completed. The electrical signal is important because it leads to contraction which in turn create pressure that moves blood. Therefore, depolarization of the SA node is important to keep a normal heart rate. If there was a problem with spontaneous depolarization of the SA node, the AV node would control the heart rate. This would cause a lower heart rate. 

Apoptosis Background

Submitted by sditelberg on Wed, 02/20/2019 - 15:15

Apoptosis is a crucial cellular function that can become misregulated in cancers, along with cell growth and proliferation. It can be activated in multiple ways throughout the cell, but is mainly characterized by two pathways: intrinsic and extrinsic. The intrinsic pathway is activated in response to cellular stress, which then affects the mitochondria either by swelling through pores or increasing permeability of the membranes (Kroemer et al. 2007). Second mitochondria-derived activator of caspases (SMAC) proteins are then released into the cytoplasm, which deactivate inhibitor of apoptosis proteins (IAPs), allowing the caspases involved in apoptosis to become active (Fesik and Shi, 2001). The extrinsic pathway of apoptosis is activated in response to external signals, which bind to receptors of the tumor necrosis factor (TNF) families. The binding of these ligands to their receptors can activate caspases and indirectly activate transcription factors involved in the inflammatory response and cell death (Adler 2007).

Week5 Draft3

Submitted by mqpham on Wed, 02/20/2019 - 14:05

Speciation is the evolutionary process by which new species arise. Although the definitions of what a species is does vary, the mechanisms by which these differences among species arise is consistent. Two types of speciation are sympatric and allopatric speciation. In sympatric speciation, a single species diverges to become two distinct species due to sexual preferences, a separation by a reproductive barrier, or polyploidy. Over time, a single area may have a population experience distruptive selection. For example, a group of beetles that breed within flowers of a plant, but if the plant has a mutation and produces a new colored flower, one that would attract certain beetles, the separation and preference causes the species to diverge. This is an example of pre-zygotic, behavioral isolation. In allopatric speciation, a separation, a geographic barrier between a once united group may cause the species to diverge. For example, in a pool that dries up and creating smaller pools, the fish that were once together are now separated geographically. Over time, the fish will exert a preference for their own kind if re-united. This too, is an example of speciation of a single species, now separated by preferences due to evolution.


Submitted by cynthiaguzma on Wed, 02/20/2019 - 13:39

“Some opponents of active euthanasia do not oppose it morally but worry that if doctors have the power to kill patients, they may use it too freely. Thus, much of the opposition to active, voluntary euthanasia comes from the fear that, if it is legalized, it will be abused. (1)” Giving a doctor far too much power and control gives humans a large sense of vulnerability. Doctors already have a control over other’s lives; euthanasia would not be any different. For euthanasia a patient must be the one to decide what will happen to them as well as have to sometimes undergo a psychological test to ensure that their decision is definite. “Advocates of physician-assisted suicide insist that it is inherently voluntary. The doctor prescribes the lethal medication, but the patient must choose to swallow the pills. (1)” Both of these versions it is the patient who is the one who desires to end their life and who makes the ultimate decision in going through with the process. These people are willing patients who have gone through a life that will not get any better, usually having an incurable disease.


Submitted by cynthiaguzma on Wed, 02/20/2019 - 13:33

Momentum is always conserved in elastic and inelastic collisions. In the simulations that were conducted what was changed was the mass of object 1 and 2, the velocity with the both objects, and whether or not the collision was elastic and inelastic. In all the trials that were conducted what was found was that the total momentum throughout the collision stayed the same. In the first trial the mass for both objects was 1 but the velocity for one was 1 and the other was 0, what happened to the total momentum was that it was one before and after the collision. With this trial it was an elastic collision which mean the objects would bounce apart. For the second trial it was an inelastic collision, which meant the objects would stick together, using the same masses and velocity as the previous trial what was found was that the total momentum in the beginning was 1 as well as in the end. In the next trials the mass was changed but the momentum was not because it stayed the same. From all the data that was collected it can be concluded that momentum is conserved in elastic and inelastic collisions.



Submitted by cynthiaguzma on Wed, 02/20/2019 - 13:31

There are three different ways which are mainly used to treat this disorder which are: Medications, Therapy, and Electroconvulsive therapy. The medications used are anti psychotic drugs which shows substantial improvement in a patient when taken.. Using medications is a lifelong commitment for the patients, if the medications are stopped a relapse may occur.(Drugs) There are four main types of therapies used for schizophrenic patients, these are: individual psychotherapy, rehabilitation, family education, and self-help groups. Individual psychotherapy involves sessions between a therapist and patient in which they discuss past problems as well as current ones. This sometimes leads the patient to be able to differentiate between reality and what is not reality which is just occurring in the patients mind. Those with schizophrenia can become better if they have families who are involved with them, that is family education. Self-help groups also help a person with schizophrenia since it gets the patient more socially involved as well as giving them access to outside sources in which it enables them to get the help they need from others. With help from others they can receive information that they had not previously had. (Therapy) Electroconvulsive therapy is when, “pulsed electricity is sent through electrodes that have been placed on a patient’s head, inducing a brief seizure.” (Roleff) This form of treatment has some side effects which include temporary memory loss. Though this is a form of treatment, studies have shown that using electroconvulsive therapy is rarely effective when treating chronic schizophrenia. This makes electroconvulsive therapy not the best choice if  looking for recovery or stability.


Spinach vs. Kale Chloroplast

Submitted by sharrath on Wed, 02/20/2019 - 13:12

In this experiment, we concentrate on the absorbance rate of chloroplasts that have been extracted from two different leaves; spinach(Spinacia oleracea) and kale(Brassica oleracea var. sabellica). Usually during photosynthesis, NADP+ is reduced to NADPH however, in this experiment we use an artificial electron acceptor, Dichlorophenolindophenol(DCPIP). Using the DCPIP, allows us to fully monitor the photosynthetic rates of each of the isolated chloroplasts. Both spinach and kale have very distinctly different coloration; kale which has a much darker pigmentation and spinach which is more on the lighter side of green. Kale will result in a lower absorbance rate in comparison to the spinach chloroplasts because of this difference in coloration. Kale has a much darker pigment than spinach, which leads us to believe that this difference in color is associated with the amount of chloroplasts found in the kale leaf resulting in a higher rate of photosynthesis. A higher concentration of chloroplasts found results in a darker pigment, lower absorption, more electrons being transferred in the ETC and a higher rate of photosynthesis

Drosophila melanogaster

Submitted by sharrath on Wed, 02/20/2019 - 13:08

I have been studying how hormones control the first stages of development in one species of fruit flies, Drosophila melanogaster. Flies are known as a model organism, which means that they are used to understand the biology of other organisms. Fruit flies share about 75% of the genes that cause disease in humans and that is exactly why scientists are often experimenting with them (Service, Elizabeth). In insects, two major hormones control the timing of their development; juvenile hormone and ecdysone. The juvenile hormone reaches its greatest concentration when the egg hatches, entering the larval stage. When juvenile hormone amounts decrease throughout the stages, this triggers prothoracicotropic hormone, leading to the pupal stage for the fruit fly.

What is Perfect?

Submitted by sharrath on Wed, 02/20/2019 - 12:59

In a world that we live in today, there is constantly pressure around us pushing us to be as “perfect” as we can be. But what exactly is defined as being ‘perfect’? One’s ideal version of perfection can be the complete opposite of another, and because of these distinctive perspectives people will continuously judge and be judged. Along with these judgmental views come one’s insecure thoughts. Insecure thoughts are only derived from our own sense of self and how we compare ourselves to others.  We as human beings have a strong desire of wanting to be approved and accepted and that is exactly why we care so much about society's opinions. Family, friends, school mates, media and even strangers are all outside sources that all have some type of contribution to our own mentality. The people that we interact with on a day to day basis all have different ideas of who we should be and we know very well that the most important perspective is our own. However, sometimes we tend to seek confirmation from these people based on their desires which may not even end up creating any fulfillment in our own lives. Why do we even end up caring?

Gene-edited Babies

Submitted by lgarneau on Wed, 02/20/2019 - 12:29

In 2018 the news of the first gene-edited baby ignited a firestorm. Chinese researchers edited these children's genes by using CRISPR/Cas9 to block HIV infections. This received a lot of backlash because of the ethics behind it. Many people believe that implanting gene-edited embryos to create babies is premature and exposes the children to unnecessary health risks. Alike vaccinations, many people believe that putting these into your system, it will have the opposite effect and may make you more likely to develop the illness. So far, the evidence shows no adverse effects however the babies have not had a long enough time living to determine anything. The researcher went on to explain that another woman is participating in the gene-editing trail and she is in the early stages of pregnancy.


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