Cell Specialization: Cardiomyocytes

This is a picture of cardiomyocytes that are about 1 month old under a microscope, taken by me in a lab at Stanford. Cardiomyocytes are heart muscle cells, and they are located within the human heart. Cardiomyocytes are 0.02mm wide and .1 mm long, making them short, narrow, and rectangular. Similar to a skeletal muscle cell, cardiomyocytes are marked with grooves of skinny dark and light bands. These cells contain one nucleus, and mostly have the same organelles of a typical eukaryotic cell, but they have many mitochondria, as they need a lot of energy in order to contract. One unique feature of cardiomyocytes is that there are irregularly spaced dark bands between the cells, which are called intercalated discs. They essentially act as a "glue" that allows all the cells to contract in unison.  The main function of Cardiomyocytes is to contract, so that as a whole, it is the driving force that pumps blood and other nutrients to the entire body. These cells are also responsible for controlling a steady, constant rhythmic heartbeat. Cardiomyocytes form interlacing bundles that become heart muscles tissue, and these cells make up one of the three major types of muscles.

Please see Works Cited page for the resources that I used.

The Sweetest Lab Ever!

In our first lab, we learned different structures and functions of various carbohydrates, and then conducted a taste test to see how the structure of the carbohydrate affected its sweetness. The relationship we found between the structure and taste was that the fewer rings a carbohydrate had, the sweeter it tasted. Monosaccharides such as glucose and fructose tasted much sweeter than polysaccharides such as starch and cellulose. Fructose was the sweetest carbohydrate, and it is used in high fructose corn syrup to sweeten many manufactured foods. Lactose is from milk, and has a distinct remnant of milk in its aftertaste. Finally, starch tasted a little papery, which makes sense as paper is essentially made from the starch of trees. 

According to NPR, in the human body, our sense of taste is centralized on our tongue, and the tip of the tongue has the sweet receptors to taste. When our tongue tastes a sweet substance, the substance is reacting chemically with with the taste buds on our tongue. When the sweet protein receptor meets the sweet substance, the taste buds send a signal to the brain which makes the body react to sweetness.