Tutor profile: Luke W.
Describe a few differences between LDL and HDL. Include major function, Which one's considered "good" cholesterol? Which one's considered "bad" cholesterol? Why?
LDL (Low-Density Lipoprotein) facilitates forward cholesterol transport out to tissues from the liver. It is mostly composed of cholesterol and is considered "bad." HDL (High-Density Lipoprotein) facilitates reverse cholesterol transport from the periphery back to the liver. It is composed mostly of proteins and is considered "good." It should be noted the lipotrotein are transport apparatuses composed of both lipids and protein components. Their structure and function is dependent of the apoproteins which are bound to them.
Subject: Biomedical Science
Patient presents with medially deviated left eye after an anterior temporal lobectomy. Physical exam notes PERRL and normal accommodation reflex. Describe which nerve/Cranial Nerve you suspect may have been nicked during the surgery.
Abducens Cranial Nerve VI was likely injured. This Cranial Nerve innervates the Lateral Rectus muscle, which abducts the eye. Without baseline muscle tone from the Lateral Rectus to oppose muscle tone from the Medial Rectus on the opposite side of the eye, the eye deviates inward, or medially.
Red Blood Cells (RBC or erythrocytes) do not contain mitochondria and rely exclusively on glycolysis for ATP production. Identify the two enzymes in the glycolytic pathway responsible for producing this ATP. What kind of phosphorylation this an example of (oxidative or substrate-level phosphorylation)? How many total, or gross, ATP are generated from from 1 glucose molecule?
In glycolysis, the two enzymes responsible for ATP generation are Phosphoglycerate Kinase (step 7) and Pyruvate Kinase (step 10). This is a perfect example of substrate-level phosphorylation, as a phosphate group is being directly moved from one molecule to another. Both Phosphoglycerate Kinase and Pyruvate Kinase catalyze reactions which generates 1 ATP. Because glucose (a 6-carbon molecule) is cleaved into two 3-carbon molecules at step 5 of glycolysis, and because both of these enzymes act on 3-carbon intermediates down stream of this glucose cleavage, each glucose molecule yields a total of 4 ATP
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