alanhu's blog

The hormones in the gut act with the brown fat to determine “fullness”. Fullness is a feeling when a person’s stomach is bloated and would not be able to consume any more food at that given time. The hormone secretin, causes a change in the intensity and behavior. When secretin is secreted it causes a loss in appetite. The more you eat the more secretin would be secreted, which would cause the person to consume less food. When you are feeling hungry it is due to less secretin being produced, and would cause the individual to feel like eating more.

Ink is secreted through two glands, the ink sac, and the funnel organ. Ink sacs were evolved by proliferation, rapid reproduction of cells, of the lower intestine. The cells of the hind gut were proliferated and mutated into the ink sacs and within those ink sacs, there are ink glands. The ink glands are where ink is released into the ink sac lumen for storage. The funnel organ is the gland where the mucus part of the ink is produced. The funnel organ is composed of two lateral pads of epithelial tissue. The epithelial tissues contain secretory cells that release the mucus. Mucus is a polymer of mucous and serous cells. Serous cells are made up of bodily fluids that resemble a serum. Mucous and serous cells are made up of inorganic salts and enzymes which do not mix together, therefore, it is a colloid. Which is why mucus is chunky and sticky. The ink that is being released is a mix between the melanin produced from the ink glands and the mucus from the funnel organ.

The use of cannabis has become widespread, especially among young adults. It was found that the use of cannabis was associated with an increased risk of depression and suicidal ideations within young adults. An active ingredient in cannabis is THC, which affects the brain by binding to the cannabinoid receptors. When THC binds it disrupts various mental and physical functions. A natural neurotransmitter that binds to the cannabinoid receptor is anandamide, which influences pleasure, memory, thinking, concentration, movement, coordination, sensory and time perception. THC acts as an agonist and binds in the cannabinoid receptor.

From the left ventricle, the blood clot flows through the aortic valve into the aortic arch. From the aortic arch, the blood clot flows into the brachiocephalic artery where it splits into the right subclavian artery and right common carotid artery. Following the right subclavian artery, the subclavian artery runs along the first rib laterally until it is under the clavicle. Once the right subclavian artery reaches the clavicle it is known as the axillary artery. The axillary artery continues down to the arm and is known as the brachial artery.

Monoamine neurotransmitter agonists are used to treat depression. Monoamineoxidase inhibitors (MAOIs) are use to inhibit enzymes that destroy monoamines. Monoaminesoxidase is an enzyme that destroys monoamine neurotransmitters in the synaptic cleft. So if the receptor was inhibited then neurotransmitters can stay in the synaptic cleft for longer. Tricyclics incresae the norepinephrine and serotonin by blocking reuptake. Reuptake is an ability of the presynaptic cleft to absorb any of the left over neurotransmitters back into the neuron. Having the neurotransmitters stay in the synaptic cleft for longer allows for more chances for the neurotransmitters to bind. Selective serotonin reuptake inhibitors (SSRIs) are used to increase serotonin within the synapse by blocking reuptake. Specifically it blocks the transporter on the presynaptic neuron. 

The heart requires its own blood supply, stemming from the aorta is the coronary artery which splits into left and right. The right coronary artery on the right side of the heart. The marginal artery branches off and supplies the right atrium with blood. Continuing along to the posterior of the heart. The posterior interventricular artery supplies the ventricles with blood. The left coronary artery is on the left side of the heart. The circumflex artery branches off and wraps around to the posterior of the heart, supplying the left atrium with blood. The anterior interventricular artery, which is branched off the left coronary artery goes down the anterior side of the heart supplying the atrium and left ventricle with blood. All the deoxygenated blood is then drained by the cardiac vein. From the cardiac vein the blood goes into the coronary sinus. From the coronary sinus the blood goes into the right atrium.

The use of cannabis has become widespread, especially among young adults. It was found that the use of cannabis was associated with an increased risk of depression and suicidal ideations within young adults. An active ingredient in cannabis is THC, which affects the bring by binding to the cannabinoid receptors. When THC binds it disrupts various mental and physical functions. A natural neurotransmitter that binds to the cannabinoid receptor is anandamide, which influences pleasure, memory, thinking, concentration, movement, coordination, sensory and time perception. THC acts as an agonist and binds in the cannabinoid receptor.

The article (https://neurosciencenews.com/dopamine-cognitive-ability-10788/) mentions that the right amount of dopamine in the brain will improve cognitive function. Tyrosine is a precursor for dopamine. Tyrosine is a polar amino acid.  An experiment was conducted where participants were given tyrosine juice or a placebo. Then the participants were given a memory task where they viewed a bunch of slides and took note of if there were any replicates. The participants who had an increase in dopamine levels with the tyrosine juice performed at a "faster rate with fewer mistakes". In class I learned that dopamine is responsible for attention and motivation. Participants who had the extra dopamine would have a higher level of attention and would pick up on more details. Also their motivation to complete the task would be higher too. Therefore, the level of dopamine in our system to function at a higher level is not always met. My question is if there is an optimal level of dopamine for the brain to function at that level, why is the brain not constantly producing dopamine to reach that level?

Ventromedial prefrontal cortex is part of the prefrontal cortex that is responsible for processing risks and fears. Researchers believe that the use of transcranial magnetic stimulation (TMS) would be able to stimulation the circuitry. 25 participants with cocaine addiction and 24 participants with alcohol addictions volunteered to be in the experiment. Brain scans of the participants were taken when the participant was given a drug cue, which causes the patient to desire the drug. Then after receiving TMS the participants showed reduced activity when the drug was mentioned. The study is important because it provides evidence that addiction is partly a brain disorder.