Sparknotes Test 1: Bio-M SATII Questions

<p>hey, can somebody help me answer questions 49-52 on the sparknotes bio-m test 1 please? :D</p>

<pre><code>Questions 49–52 Red cabbage (Brassica oleracea capitata rubra) can serve as a natural indicator—its pigments change color in response to varying pH levels. A student chops and boils half a red cabbage head for ten minutes and then strains it to obtain a purple liquid. The liquid is then cooled to room temperature and separated into beakers. The student adds various substances to each beaker and observes the changes.

<li><pre><code>What can the student determine about red cabbage as a natural indicator?

<p>(A) It turns pink in the presence of acids.
(B) It turns red in the presence of bases.
(C) It turns blue-green in the presence of acids.
(D) It is purple at a pH lower than 7.
(E) It is a poor indicator of acidic or basic solutions. </p></li>
<li><pre><code>What would the student observe if sodium hydroxide (NaOH) was slowly added to the vinegar solution?

<p>(A) The solution would turn from pink-red to purple to blue-green.
(B) The solution would turn from pink-red to pink to yellow.
(C) Nothing—the reaction has already occurred.
(D) A white precipitate would form at the bottom.
(E) The solution would turn clear. </p></li>
<li><p>Plants get much of their color from pigments, such as chlorophyll. What is the function of red cabbage pigments in nature?
(A) Indicate the pH of the soil
(B) Contribute to photosynthesis
(C) Keep down heat absorption
(D) None: vestigial structure
(E) Attract animals </p></li>
<li><p>When added directly to leaves of red cabbage, such as in salad, vinegar effects no color change. What best explains why?<br>
(A) Vinegar is too weak a substance to change the indicator.
(B) Nothing can penetrate the epidermis of plant cells.
(C) Red cabbage neutralizes the vinegar.
(D) Hydrogen ions cannot independently cross cell membranes.
(E) The indicator only works at higher temperatures. </p></li>

<p>Thanks in advance :)!</p>