BSC 1020: The Molecules Of Life

BSC 1020 – Homework Unit B

The Molecules of Life

This homework is worth 25 points of the 900 points available in the course.

Please use the book, PPT lecture handouts, and internet to answer the following six questions:

Question 1 (8 points) Mr. Tony, a biology teacher, gives his student Ziad four samples and tells him they are lysine (an amino acid), lactose (a disaccharide), insulin (a protein hormone), and RNA. The samples are in test tubes marked 1, 2, 3, and 4, but Ziad is not told which compound is in which tube. He is asked to identify the contents of each tube.

a. In his first test, Ziad tries to hydrolyze a portion of the contents of each tube.
Hydrolysis occurs in all tubes except tube 3.

b. In the next test,
he finds that tubes 1, 2, and 3 are all positive for nitrogen, but only tube 2 contains a sample that is very rich with carboxylic acid groups.

c. The last test he performs shows that the compound in tube 1 contains a high percentage of phosphate.

Based on these data, fill in the following table and explain your answers.

Tube
Contents
Explanation

1 RNA RNA is made of phosphate groups.

2 Insulin Insulin is known as a protein made of amino acids that consist of different carboxylic acid groups.

3 Lysine Lysine cannot be hydrolyzed due to the fact that it is a monomer.

4 Lactose Lactose doesn’t contain nitrogen.

Question 2 (4 points) On April 20, 2010, an explosion occurred on the Deepwater Horizon offshore drilling rig, operated by British Petroleum off the coast of Louisiana, starting a massive oil spill in the Gulf of Mexico.
Before it was capped, the well 5000 feet (1500 meters) below the sea surface leaked at least 200 million gallons of oil. (Some estimates are far larger.) One tactic BP used was to spray hundreds of thousands of gallons of DISPERSANTS into the gushing clouds of oil and onto surface of the ocean. Dispersants are a mixture of organic solvents and detergents which enable the oil to mix into the water. While this largely succeeded in getting the oil “out of sight, out of mind” by diluting it into a much larger volume of water below the surface, and helped increase of speed of chemical and bacterial breakdown of the oil somewhat, much of the oil is still there, just spread out more, and the dispersants themselves are also quite toxic. The full environmental damage of this spill and its “cleanup” will take years to
assess.

Explain how dispersants are able to get oil and water to mix. Be sure to mention terms discussed in Chapter 3, such as surface tension, and hydrophilic/hydrophobic.

Dispersants are chemicals sprayed over an oil spill that reduce the surface tension (measure of how difficult it is to stretch or break a liquids surface) that normally stops water and oil from mixing. Water is hydrophilic or in other words “water loving” while oil is naturally hydrophobic meaning “water hating” so the two naturally don’t mix well. But with the help of dispersants they are able to mix the oil and water allowing the oil to sink to the bottom of the ocean.

Question 3 (5 points) Speaking of oil ….. In 1996, while examining sandstone cores from an oil exploration drilling program in Australia, geologist Dr Philippa Uwins discovered filaments she called nanobes. These minute structures, which are about 1/10th the size of the smallest bacterium, have generated a lot of debate since then. Some scientists claim that they are alive, while others state emphatically they are not.
Give 3 reasons that suggest nanobes are alive, and 2 reasons suggesting they are not. For complete credit each reason should consist of a complete sentence.

Alive
1. Nanobes are thought to be alive because there is some evidence that they may have cell membranes.
2. When observed under a microscope nanobes appear similar to regular acinobacteria and forms of fungi.
3. Nanobes are also thought to be alive because they are able to divide cells.

Not Alive
1.
Some argue that nanobes cannot be living because they are so small.
2. Another reason nanobes are thought to be non living is because they lack evidence of having DNA.

Question 4 (5 points) In addition to being vital to life itself, enzymes are utilized by humans in various ways, such as dietary supplements and consumer goods. Investigate the use of enzymes in the products below. For complete credit, each answer should consist of two complete sentences.

• Beano
Beano is a product that attempts to reduce gas in the digestive system. It reduces bloating and stomach discomfort as well. It’s made up of digestive enzymes that break down carbohydrates as well as complex sugars.

• Mannastar
Mannastar can be found in most soap, cleaning products and detergents. Its purpose is to break down stains and any residue.

• Stonewashed Jeans
The process of stonewashing jeans gives them a stretchy texture and a worn out look. The cellulose breaks down some of the molecular bonds however it does no damage to the interior of the cotton fibers.

• Lactaid
Lactaid is a dietary supplement that consists of the lactase enzyme. This enzyme helps break down the sugar found in dairy products.

•
Candidase
Candidase is made up of two enzymes, cellulose and protease. The two together help control the overgrowth of yeast.

Question 5 (3 points) Phosphorus (P) has an atomic number of 15, and a mass number of 31. How many electrons, protons, and neutrons does the potassium atom contain? For complete credit, you have to show how you arrived at your answer.

The atomic number of an element is equal to the number of protons it consists of. Protons and electrons are balanced meaning the there are also 15 electrons. To calculate the number of neutrons you must take the mass number and subtract by the number of protons (31-15=16). So there are 15 protons, 15 electrons, and 16 neutrons.