Question

23. Every enzyme functions best at A. high pH. B. low pH. C. optimum pH. D. neutral pH. 24. Which of the following is an example of an enzyme-substrate complex? A. glucose B. glucase C. vitamin D D. sucrose-sucrase 25. An example of an enzyme is A. maltose. B. fructose. C. hydrogen peroxide. D. dehydrogenase. 26. Which of the following is (are) component(s) of all cells? A. plasma membrane B. DNA C. cytoplasm D. nucleus E. a, b, and c 27. If a membrane only allows certain types of substances to go through, then the membrane is called A. facilitated diffusing B. active transporter C. selectively permeable D. permanently permeable E. gradiently soluble 28. Rod shaped bacteria are referred to as A. Bacillus B. Coccus C. Spirillum D. None of the above 29. The iodine test is used to test for the presence of what organic molecule? A. Proteins B. Lipids C. Starch D. Simple sugar

Answer 1

QUESTION 23: Every enzyme works best at their optimum pH.

Correct answer is (C)

QUESTION 24: In hydrolysis of sucrose,

Sucrose - substrate

Sucrase - enzyme

I.Sucrose binds at the empty Active site of sucrase

II. subtrates is converted to products

III. products are released (Glucose and fructose).

Correct answer is (D)

QUESTION 25: hydrogen peroxide is a substrate.

Maltase is an enzyme that catalyses the hydrolysis of maltose to simpler sugar.

Dehydrogenase is an enzyme which belongs to oxidoreductase group.

Correct answer is (D)

QUESTION 26: All cells have a plasma membrane, cytoplasm, genetic material (DNA) and ribosomes.

Correct answer is (E)

QUESTION 27: Selectively permeable membrane only allows certain types of substances to pass through.

Correct answer is (C)

QUESTION 28: ROD shaped bacteria are referred to as bacillus or Bacilliform bacterium.

Correct answer is (A)

QUESTION 29: IODINE test is used to test for the presence of starch. In the presence of starch, the brown colour of the aqueous solution turn 'blue-black'. ( Remains the same in the absence of starch)

Correct answer is (C)