Optometry Admission: OAT

PLASTICS

Plastics have long been considered one of the great conveniences of the modern era, but evidence is mounting to indicate that these conveniences have come at an incredible cost. The chief benefit of plastics is their durability, but this benefit turns out to be the same reason plastic has become a significant problem: It takes 200 to 400 years to decompose. All of this plastic has accumulated into a catastrophic mess and has also caused disease in humans.

Between Hawaii and Japan, a giant mass of plastic twice the size of Texas slowly swirls with the currents of the Pacific Ocean. This area has come to be known as the Great Pacific Garbage Patch, and its effects on the ecology of the ocean are unimaginable. According to United Nations researchers, a hundred thousand sea mammals and a million seabirds die each year. They are found with cigarette lighters, syringes, and other plastics that they mistake for food in their stomachs.

Evidence also indicates that the plastic receptacles that people store their food in poses health risks. For instance, phthalates have been shown to have detrimental effects on the reproductive system, yet they are found in many plastic products including baby bottles and water bottles. They have also been linked to various forms of cancer. Additionally, a chemical called bisphenol A that is found in many plastics can mimic the effects of the hormone estrogen, which can also affect the reproductive system.

Which of the following best describes the author's purpose in writing this passage?

A. To persuade readers to accept the author's point of view.

B. To explain the benefits of plastic.

C. To explain the risks of plastic bottles.

D. To inform the reader of the effects of phthalates in plastics.

A couple have 3 children between them, all of them boys. If they were to have another baby, what is the chance the gender will be a male?

A. 1/16

B. 1/4

C. 1/2

D. 1/32

E. Cannot be determined.

A double-stranded DNA molecule consists of 20% Guanine. What percentage does Thymine represent in this stand?

A. 20%

B. 30%

C. 40%

D. 60%

E. 80%