Biological Macromolecules Macromolecules Introduction to Biology with Lab
Hannah Barlow
Introduction:
This experiment was meant to teach us the four kinds of macromolecules: proteins, lipids, carbohydrates, and nucleic acids. We are to perform 4 tests which will determine if the four macromolecules are present. A Macromolecule Macromolecule is a large molecule molecule that that has small small molecules molecules that link together. together. There are four kinds of macromolecules. These include: lipids, proteins, carbohydrates, and nucleic acids. ipids are organic compounds that are oily when touching and are not soluble. !xamples of lipids are: waxes, oils, steroids, fatty acids. This would include fish, sunflower seeds, canola oil, and green "egetables. ipids are "ery beneficial for the body. They allow brain function, protecti"e layer for organs, natural steroids, and supporting the reproducti"e system. #n this experiment we will use $udan ### to test for lipids on filtered paper. %roteins are long chains of amino acids. These amino acids are compounds made up of one amino group and one carboxyl group. There are two types: essential and nonessential. #n total, there are twenty. #n this experiment, we will use &iuret's reagent to detect if there are proteins present. (arbohydrates are the body's main source of energy. They can be stored for )uick use, immediate use, or later use. (arbohydrates are produced in green plants during photosynthesis. There are to types of carbohydrates: simple and complex. $imple carbohydrates are also known as simple sugars. (omplex carbohydrates are at least three linked sugar molecules. (omplex carbohydrates are often found in whole grain foods, yams, and beans. #n this experiment, we will use &enedict's reagent to find reducing sugars that are present, and the #*# solution is used to find the starch present in foods. +ucleic Acids are long chains of +A or -+A. &oth +A and -+A are called nucleotides which include: a phosphate, sugar, and nitrogenous base. These are essential and responsible for all the genetic makeup of all li"ing organisms. As the positi"e positi"e controls controls in in our experiments experiments we ha"e: ha"e: glucose glucose for the sugar test, test, starch starch and the potato for the starch test, "egetable oil for the lipids, and milk for protein. or the unknown, # would say we will be able to know exactly what it is by the end of this experiment and what category it belongs under.
Methods and Materials: ITEM (Student Supplied)
NEEDED
Bottle of Distilled Water
1
Egg
1
Boiling Water
1
Roll of paper towels
1
Dish Soap
1
Pencils/ Pen
1
Milk, 2%
1
Rsset Potato, raw
1
!"en Mitt
1
#ork
1
Plastic Spoon
1
$EM &'!( Spplied) #ilter Paper, Rond
2
12 in *l+in+ #oil
1
Well Plate
1
2- +( .eaker
1
leaning Brsh
1
est est .e, .e, 101--++
Safet3 glo"es
2
Safet3 glasses
1
4radated 3linder, 1- +(
1
1 plastic cp
1
1 sharpie
1
Eperi+ent .ag
1
Pipets
5
6ote.ook
1
Testing Testing for Sugars and Starches:
/. %roperly %roperly put put on safety safety glasses glasses and and goggl goggles. es. 0. 1sing the graduate graduated d cylinder, cylinder, measure measure /2m of distilled distilled water and put it in the bottled named 31+*+W+5. 6ently shake bottle to dissol"e the unknown substance into the water. 7. $eparate $eparate eggs white and and yolk. yolk. (atch (atch egg whites in plastic plastic cup. 4. 1se a marker marker to label label your your six test test tubes tubes:: -8 0, Albumin, 1nknown, Milk, 6lucose, and !gg White Albumin stock. %lace all six test tubes in the well plate for a test tube holder. 9. 1se albumin albumin pipet to to measure 2.9m of egg whites whites into the test tube named named egg white albumin stock. . 1se a pipet pipet for albumin albumin to measure 4.9m 4.9m of distilled distilled water and place place it into the the egg white albumin stock test tube. $wirl it around to mix it. %lace the pipet used into the !gg white albumin stock test tube. ;. 1se the Albumin Albumin pipet to transfer transfer /m of the egg whie whie albumin stock to the test test tube named Albumin. <. abel abel a =umb =umbo o pipe pipett d8 d8 0 and transfer /m of distilled water into the test tube. >. abel a pipet Milk and transfer transfer /m of milk into into the test test tube labeled labeled milk. milk. /2. Add 04 drops of the 1+*+W+ solution to the corresponding test tube. //. Add 04 drops of glucose to the corresponding corresponding test tube. /0.bser"e /0. bser"e the color and record. /7.&oil water. (arefully fill the 092 m beaker ? full. /4.1se /4. 1se o"en mit to protect your hands. hands. /9.Add 42 drops of &enedicts reagent to all fi"e test tubes. /.%lace 9 test tubes into the boiling water and allow samples to sit for /2 minutes. /;.After /2 minutes, remo"e test tubes from water, and return them to the well plate. /<.bser"e and record the color. />.#f color is brown, a reducing sugar is present. 02.When you're done, pour all test tubes out with lots of water, and wash and dry test tubes. 0/.1se 0/. 1se the marker to label fi"e test tubes as: d8 0, albumin, 1+*+W+, milk, and starch. %lace all test tubes into well plate. 00.1se the 3Albumin5 pipet to measure / m of the egg white albumin stock solution into the test tube named Albumin. 07.1se the d80 pipet to measure / m of distilled water into the corresponding test tube. 04. 1se the Milk pipet to transfer / m of milk into the corresponding test tube. 09. Add 04 drops of $tarch from the bottle to the $tarch test tube. 0. Add 04 drops of 1+*+W+ from the bottle to the 1+*+W+ test tube. 0;. 1se the spoon to get a small amount of potato. ea"e the potato in the center of the spoon. 0<. bser"e the color the 9 test tubes and the potato and record.
0>. 1se the marker to label a pipet with #*#. 72. 1se the #*# pipet to measure / drop of #*# solution from the glass bottle into each of the 9 test tubes and to the potato. 7/. bser"e and record the colors of the 9 test tubes and the potato. 70. A black color indicates the presence of starch in the test tubes. bser"e and record data. 77. When data has been recorded, pour the contents of the 9 test tubes down the sink. Wash and dry the 9 test tubes. Testing for Proteins and Lipids:
0. 1se a marker to label 4 test tubes as follows: d80, Albumin, 1+*+W+, and Milk. %ut the test tubes in the well plate. 7. 1se the Albumin pipet to measure / m of the !gg white albumin stock solution into the test tube named Albumin. 4. 1se the d8 0 pipet to measure / m of distilled water into the corresponding test tube. 9. 1se the Milk pipet to transfer / m of milk into the corresponding test tube. . Add 04 drops of 1+*+W+ from the bottle to the corresponding test tube. ;. bser"e the color of the 4 test tubes and record. <. Add 9 drops of &iuret's reagent to each of the test tubes. >. bser"e and record the color. /2. Allow the samples to incubate for 9 minutes. //. After 9 minutes, obser"e and record the color again. /0. A purple color means that is it a positi"e for protein. ecord data. /7. %ut aluminum foil on a flat surface and put / piece of filter paper on the Aluminum foil. /4. 1se a pipet to get the $udan ###. /9. %ut / drop of $udan ### in 9 places on the filter paper. /. Allow the drops to completely dry before going on to the next step. /;. 1se a pencil to outline each of the 9 circles. abel the circles as: 1+*+W+,
Albumin, -istilled water, water, Milk, and @eget @egetable able oil. oil. /<. 1se the d8 0 pipet to put / drop of distilled water to right circle. />. 1se the Milk pipet to put / drop of milk to the milk circle. 02. 1se the Albumin pipet to put / drop of albumin to the albumin circle. 0/. 1se the bottle of the 1+*+W+ to add / drop of 1+*+W+ to the corresponding circle. 00. 1se the bottle to put / drop of canola oil to the oil circle. 07. Add $udan ### to all circles. Allow it to sit for 72 minutes. 04. After 72 minutes. bser"e and record whether the color leaked past the circle lines. 0. Wash and dry all e)uipment. Results:
&enedict's eagent $ample d80 Albumin 1+*+W+ Milk 6lucose
#nitial (olor (lear ight yellow yellow clear white Milky whiteclear
inal (olor blue &lue and and brown &lue purple and blue &rown and blue
$ugar %resent: yn + B + + B
#nitial (olor clear clear (lear White Milky (lear Bellowbrown
inal (olor edyellow (learbrown (learbrown edyellow Whitebrown &lack &lack
$tarch: B+ + + + + B B
ugol's #odine $ample d80 Albumin 1+*+W+ Milk $tarch aw potato &iuret's eagent $ample
#nitial (olor
d80 Albumin 1nknown Milk ipid
&luebrown (lear (lear White
$ample
#ntermediate (olor ight blue %urple %urple %urplewhite bser"ations
inal (olor
%rotein: B+
ight blue %urple %urple %urplewhite
+ B B B
ipid: B+
-istilled water Albumin 1+*+W+ Milk @egetable il
-id not run outside lines $tayed within circle circle $tayed inside circle $tayed inside circle Went outside of lines
+ + + + B
Discussion/Conclusion:
#n the test for reducing sugars, Albumin and 6lucose tested positi"e. &oth the Albumin and glucose test tubes had brown, which is positi"e for sugar. The test that confused me was the milk, because the milk has some sugar in it, so # figured it would'"e been positi"e. # think the d8 0 was the negati"e control because of common knowledge, we know it does not contain sugar. #n the test for starch, the positi"e control was ob"iously starch. The negati"e control was d80, because like # said before we know there isn't starch in it. # knew from prior knowledge, the potato would be "ery black, and the test did in fact pro"e that. All others were negati"e, and so the unknown is not a starch either. #n the test for protein, our negati"e control was the d8 0 once again, because we know it is only water. ur positi"e control was the milk, because we know it contains protein, and the test pro"ed that when it turned purple. The Albumin and unknown also turned purple, so we know the 1nknown is a protein. #n the test for lipids, the "egetable oil was ob"iously the positi"e control in this test. The distilled water was yet again our negati"e control. The only test that showed positi"e was the "egetable oil because it went outside of the circle lines. The unknown is a protein. # cannot identify what it is, so, # was incorrect. # can tell if it was a lipid, protein, sugar, or starch, but not exactly what it is. Works Cited
(ampbell, +eil A. &iology: (oncepts and (onnections. $an rancisco, (A: %earson !ducation, 0229. %rint 8andsCon abs, #nc.40C20>/C22C20. 8andsn earning. ab %a). Web. 20 eb. 02/. Dhttp:www.8science.comE