A slice of apple left on a table slowly goes brown due to an enzymatic reaction. Dipping the apple slice in lemon juice prevents it from browning Which of the following best explains this result?

A. Lemon juice has enzymes which reverse the browning reaction

B. Lemon juice has a pH which inactivates the enzymes

C. Lemon juice functions to bleach the brown material

D. Lemon juice functions to dilute the brown material

Answer Explanation:

Browning of the apple surface is due to the action of the enzyme polyphenol oxidase. Lemon juice is acidic and lowers the pH of the apple's surface. This inactivates the enzyme polyphenol oxidase, which works best at a neutral pH. This in turn reduces the browning action on the apple.

Therefore, the Correct Answer is B.

Q #1: The component of an atom that possesses relatively little mass, thus being negligible in calculating the atomic mass number, is the:

A. Electron

B. Quark

C. Neutron

D. Proton

Answer Explanation

Rationale

Electrons are subatomic particles that have relatively little mass and are negligible when calculating atomic mass. The atomic number is usually the sum of protons and neutrons in the nucleus of the atom.
Q #2: Parasitic worm infestation is hypothesized to be damaging to the host. However, scientists have recently discovered that worm infestation can relieve the effects of certain autoimmune disorders, in which of the following ways should the hypothesis be modified, given the new findings?

A. Lack of worm infestations is the cause of some autoimmune disorders.

B. Worm infestation reduces the severity of certain autoimmune disorders

C. Worm infestation prevents the body from immune malfunction

D. Worm infestations exacerbate the body's immune reactions

Answer Explanation

The new findings can be used to generate a hypothesis to reflect the beneficial aspect of worm infestations in certain autoimmune disorders, indicating that they can help reduce the severity of the condition.
Q #3: Which of the following is correct regarding the pH scale?

A. A substance with a pH of 3 is two times more alkaline than a substance with a pH of 4

B. A substance with a pH of 3 is 10 times more acidic than a substance with a pH of 4

C. A substance with a pH of 3 is two times more acidic than a substance with a pH of 4

D. A substance with pH of 3 is 10 times more alkaline than a substance with a pH of 4

Answer Explanation

The pH scale is logarithmic, indicating that each whole number change on the pH scale represents a tenfold change in acidity or alkalinity. Therefore, a substance with a pH of 3 is 10 times more acidic than a substance with a pH of 4.

Free Access on TEAS 7 Exams and Study Notes

Access to all TEAS 7 Exams
Performance Tracking and Analysis
Well Documented and Explained Questions and Answers
2000+ Questions and Correct Answers: Answers Well Explained
Libary of Detailed StudyNotes
Topical Questions and Answers on Examinable topics

Join Now

A slice of apple left on a table slowly goes brown due to an enzymatic reaction. Dipping the apple slice in lemon juice prevents it from browning Which of the following best explains this result?

More Questions on TEAS 7 Science

Q #1: The component of an atom that possesses relatively little mass, thus being negligible in calculating the atomic mass number, is the:

Answer Explanation

Q #2: Parasitic worm infestation is hypothesized to be damaging to the host. However, scientists have recently discovered that worm infestation can relieve the effects of certain autoimmune disorders, in which of the following ways should the hypothesis be modified, given the new findings?

Answer Explanation

Q #3: Which of the following is correct regarding the pH scale?

Answer Explanation

Free Access on TEAS 7 Exams and Study Notes

TEAS 7 Exams (Q&A)

TEAS 7 Study Notes

TEAS 7 Topical Tests

TEAS 7 Study Guides

Quick Links

Refer a Friend