Glucosamine

Below show the nutritional information of a bottle of glucosamine supplements commonly taken by elderly persons to alleviate joint pains. Name 2 homologous families that are present.

Glucosamine is a precursor of glycoasminoglycans, a component of the joint cartilage. Hence, it is taken as a supplement to prevent cartilage degeneration and some components such as chondroitin is said to improve its efficacy.

Fleet Fish

Article from: Discovery Channel Magazine; October 2010, pp. 32, 33

The fleet fish is the quickest marine animal in the seas and can outpace many small cars. It can travel up to a maximum speed of 110km/hour and is a sailfish of the family Istiophoridae. It is better at accelerating and can grow up to over 3m, 100kg and live up to 10 years as they have few natural predators. Their various structures and adaptations include:

1. Skin: Unique skin with V-shaped protrusions. Some researchers theroise that this help cut down skin-friction from the water. It can create vortices that change the boundary layer drag slightly, a bit like what the shark skin does.

2. Streamline: They have sickle-shaped fins or flippers, narrow lunate (crescent moo-shaped) tail fins and a classic teardrop-shaped body. All this cuts down drag to a minimum; to a stunning efficient coefficient of 0.0075 to be precise. In comparison, the highly slippery Ferrari Testarossa has a drag coefficient of 0.36.

3. Life cycle: Adult sailfish live in Atlantic and Pacific oceans, in the warm and temperate zones. Females produce millions of eggs but as the tiny fertilised larvae are a favourite food for many other fish, only a dozen or so will make it through to adulthood.

4. Speed: 100km/hour. It does so by lowering its drag (skin friction).

5. Muscle: Also contribute to its fast speed. It has a large reserve of white muscles, great for acceleration but not so goof for long swims. To make up for this, it has additional layers of red (myoglobin-rich) muscle which give stamina for longer swims. The sailfish also makes use of a network of blood vessels that help warm the red muscles, making them more efficient.

6. Sail: The exact function of the sailfish’s huge dorsal fin remains a mystery. Fishermen say it is used to help round up fish before feeding, others say it helps it manoeuvre quickly at its top speeds. It has even been likened to a radiator, for warming the fish’s blood when it is on the surface, so its red muscle can work more effectively.

7. Beak: Beak for feeding. It is necessary though it increases the overall drag. Sailfish swim into a school of fish (sardines, mackerel, anchovies), swinging their beak side to side to whack and stun the unlucky ones. Then, they swim back through the school and eat the floating and insensible victims.

I came across an advertisement in Readers' Digest about Hypocol. Hypocol is a supplement said to contain Red Yeast Rice produced by fermentation rice with red yeast for lowering blood lipid levels and cholesterol.

The product of red rice fermentation will produce monacolin K, which is similar to lovastatin, which is used to lower cholesterol levels, in terms of its structure and function. The monacolin K can inhibit the HMG-CoA reductase enzyme that is responsible for cholesterol production in the liver and hence aids in lowering the cholesterol level.

Fermentation
- Consists of glycolysis + anaerobic respiration
- Glycolysis: Breaking down of glucose; 2 ATP, 2 NADH and 2 pyruvic acid formed
- Anaerobic respiration: Oxidation of NADH and transformation of pyruvic acid into a final waste product, which is either ethanol or lactic acid, depending on the organism doing the fermenting (yeast or muscle cell).
- When yeast or some types of bacteria is used, the end result is alcohol. This has applications in beer and wine.
- When other types of bacteria is used, the end result will be acids such as propionic acid or lactic acid or acetic acid. This has applications in cheese, yoghurt, soy sauce and vinegar.

Implication for teaching:
- Can be used to teach the chapter on fermentation, enzymes, biomolecules (chloesterol).

Guiding questions for students:

1. What is fermentation?
2. What are the conditions necessary for fermentation?
3. What other applications does fermentation have?

4. What are lipids?

5. What are blood lipid levels?

6. How can cholesterol affect our health?

7. How is HypoCol said to lower blood cholesterol levels?

8. What is the chemical structure of cholesterol?