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The anatomy of the hypothalamic pituitary axis is essential to its function. The neurons from the hypothalamus which synthesize hormones to be released by the posterior pituitary gland synapse directly onto the veins in the posterior pituitary, so they can release the hormones there to be sent out to the rest of the body. The hypothalamic-anterior pituitary section has a more unique structure. There is a portal system, 2 capillary beds connected by a veinous system, that joins them. One capillary bed is in the hypothalamus and the other is in the anterior pituitary. This contrasts normal veinous systems, where an artery goes in and leaves as a vein. Instead, the two capillary systems are joined. A set of neurons in the hypothalamus produces releasing factors and synapses in the capillary bed that is also in the hypothalamus, which is connected to the capillary bed in the anterior pituitary where hormones such as ACTH, FSH, and prolactin are synthesized. This connection allows it to trigger their release. The hormones in the portal system would degrade and be at concentrations too low/dilute in the general circulation, but when contained in the smaller portal system where they can flow, they are at a sufficient concentration.
The pituitary gland is a major player in the endocrine system, the system that controls hormones in the body. The pituitary gland is often referred to as the master gland because it controls the other glands in the body. It used to be widely thought only that the pituitary gland controlled the brain, but interestingly, the brain controls the pituitary gland. The brain secretes neurotransmitters which control hormones. The pituitary has two different regions: the posterior pituitary (neurohyphosis) and the anterior pituitary (adenohyphosis). The hypothalamus (a region of the forebrain) produces the neurotransmitter oxytocin and antidiuretic hormone (also called vasopressin) inside of its neurons, and passes them along to the posterior pituitary, which secretes them into the body. Antidiuretic hormone targets the kidneys, especially its tubules, and regulates water levels. Oxytocin targets the mammary glands, facilitating lactation, as well as the uterus, controlling contractions. The hormones are made in the hypothalamus, the posterior pituitary only secretes them. In contrast, the anterior pituitary gland synthesizes its own hormones, but they cannot be released unless regulatory hormones released from the hypothalamus signal them to do so. The anterior pituitary gland secretes prolactin which targets the breasts for milk production, ACTH which stimulates cortisol release, growth hormone which acts on bones, gonadotrophic hormone which acts on sex organs, and thyroid stimulating hormone.
My picture was of a spider nestled between the rungs on a plant pot right in front of the Student Union on Campus. I selected this area because it was pretty close to the Biology Computer Resource Center, which I used as a reference point when describing the directions to the Student Union. I used the Biology Computer Resource Center as a reference point because that is where our class takes place, so I knew that the student following my Method would know its location, thus allowing them to replicate my procedure with ease. One factor that I knew I had to control was the location of the pot where the spider was. There were 4 different pots in front of the Student Union, so I had to specify which one by stating that it was the one on the end nearest the Lincoln Campus Center. I also needed to control where the picture was taken on the pot, since it was a large pot with several potential places that a spider could nestle. So I specified that the spider web was located between the vertical ridges on the pot, right above a patch of vegetation that was growing on the ground beneath the pot. Another variable that I sought to control was the platform for the creation of my image. I knew that most of the class was going to be using Inkscape, but I could not download Inkscape. I looked into Microsoft Word, mainly because it is a very popular platform, so I figured that the person replicating my image would likely already have Word. If they were not able to use the same platform as me, they would not be able to follow my procedure as precisely. I also specified the different colors of the font that I used, and when I put letters in bold. In general, the more detailed I was in my Methods, the more I controlled the different variables.
I was having a lot of trouble downloading Inkscape, despite extensive trouble shooting, following tutorials, and a trouble shooting thread on Reddit. I kept running into technical difficulties so I decided to try something else. I downloaded an app called “iDoodle” on my iPhone and tried drawing circles and arrows onto my different photos on the app, but they looked a bit messy and unprofessional. I looked up how to insert arrows and circles on Microsoft Word and found that it was relatively easy, so I chose to use Microsoft Word. I found a picture of the campus map on google by searching “Umass campus map.” I found a picture that was already cropped to a fitting segment that included the Student Union and the Biology Computer Resource Center, so I chose to use this image as my part A. I pasted it into a Word Document. For part B, I pasted the picture I took of the Student Union, and circled the pot that I found the spider on by clicking “Insert,” “Shapes,” and then “Oval” on Word, and then unfilling the oval so that it was just an outline that I could place around the pot (rather than a solid oval that would block the pot.) I changed the color of the oval from white to red. Next, for part C, I added the picture I took of the pot for reference. I added two thick red arrows pointing toward the precise location of the spider web on the pot, in between the two ridges where it was nestled. I added the arrows by clicking, “Insert,” “Shapes,” and then “Arrow.” I changed the font to red and the size of the arrows to be thicker. Lastly, I added the photograph that I took of the spider itself. I created another red oval and placed it directly around the spider, but I manipulated it by dragging the edges with my cursor so that the oval was more of a circle, which was better suited for the shape to put around the spider. I then created a textbox in the upper left corner of each of my images, filled in each textbox to have a solid white fill, and typed “A,” “B,” “C,” and “D,” respectively in each box. I bolded the font and made it size 48, then put a space before each letter to center the letter in the text box. I took a screenshot on my MacBook (pressing Command+Shift+4) to save it as a PNG.