Question

lab: identifying nutrients reflecting on the laboratory procedure throughout the reflection, make sure you have a copy of the student guide (pdf or word) and your data table. you tested for the presence of four different indicators by adding nutrients to the three test tubes. if the mystery food sample contained the nutrient, then it would change to the same color as the blank. in this lab, the only test th blank was for indicator, positive control, negative control (accompanied by an image of test tubes labeled positive control (varied), negative control (water), mystery food sample, and an indicator solution bottle).

Explanation:

To solve the fill - in - the - blanks for this nutrient - testing lab procedure:

Step 1: First blank (testing for presence of what)

In a nutrient - testing lab, we test for the presence of different nutrients. So the first blank (after "four different") should be filled with "nutrients". And the second blank (the action done by adding) is related to using indicators. We test for nutrients by adding "indicators" to the test tubes.

Step 2: Third blank (color change reference)

A positive control is a sample that we know contains the nutrient we are testing for. When the mystery food sample contains the nutrient, its color change should match the color change of the "positive control" because the positive control is supposed to show the positive result (presence of the nutrient) for the test.

Step 3: Fourth blank (type of test)

In this lab, usually, the only test that is a "negative control" is the one with water (as water doesn't contain the nutrients we are testing for, and it is used to show the negative result, i.e., no color change due to the absence of the nutrient).

Final Answers (for the blanks in order):

1. nutrients
2. indicators
3. positive control
4. negative control

(Note: The blanks in the original problem are filled in the order of the dropdowns. The first dropdown (after "four different"): nutrients; the second dropdown (after "by adding"): indicators; the third dropdown (after "same color as the"): positive control; the fourth dropdown (the last one): negative control)

Answer:

To solve the fill - in - the - blanks for this nutrient - testing lab procedure:

Step 1: First blank (testing for presence of what)

In a nutrient - testing lab, we test for the presence of different nutrients. So the first blank (after "four different") should be filled with "nutrients". And the second blank (the action done by adding) is related to using indicators. We test for nutrients by adding "indicators" to the test tubes.

Step 2: Third blank (color change reference)

A positive control is a sample that we know contains the nutrient we are testing for. When the mystery food sample contains the nutrient, its color change should match the color change of the "positive control" because the positive control is supposed to show the positive result (presence of the nutrient) for the test.

Step 3: Fourth blank (type of test)

In this lab, usually, the only test that is a "negative control" is the one with water (as water doesn't contain the nutrients we are testing for, and it is used to show the negative result, i.e., no color change due to the absence of the nutrient).

Final Answers (for the blanks in order):

1. nutrients
2. indicators
3. positive control
4. negative control

(Note: The blanks in the original problem are filled in the order of the dropdowns. The first dropdown (after "four different"): nutrients; the second dropdown (after "by adding"): indicators; the third dropdown (after "same color as the"): positive control; the fourth dropdown (the last one): negative control)