PRE LAB WEEK 2 BIO

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Student’s name: Nguyen Giang Yen Tho
Student’s ID: BTFTIU18118
PRE-LAB WEEK 2
1. What are 4 classes of biological macromolecules and their building
blocks?
o There are 4 mains macromolecules:
- carbohydrates. Those carbohydrates have their building blocks made of
monosaccharides.
- lipids. Their building blocks are fatty acids.
- proteins. Their building blocks are amino acids.
- nucleic acids. Their building blocks are nucleotides.
2. Describe structure of carbohydrate (starch, sugar).
o Carbohydrates are sugars, or long chains of sugars.
o These long chains are made of monomers known as monosaccharides, which build
up, bond together to form polysaccharides.
STARCH:
SUGAR:
o
o
o
o
Known as polysaccharides.
Made of glucoses.
General formula: (C6H10O5)n
Function: form and store
energy.
o  1,4 glycosidic bond; Linear
structure for Amylose particles.
o  1,4 glycosidic bond,  1,6
glycosidic bond; Branching
structure for Amylopectin
particle
s.
o Known as disaccharides.
o Made of glucoses and fructoses.
o Function: Form and store energy.
3. What is the difference between Lugol and Iodine solution? How can we
prepare them?
LUGOL IODINE:
o Made of Iodine and Potassium
iodine.
o Can be used as a reagent in
antiseptic and cancer diganois.
o The iodine in lugol bined to
glucoses shaped as  1,4 found
in polysaccharides, known as
glycogen.
o Preparation:
- Potassium iodide: 10 g
- Distilled water: 100 ml
- Iodine crystals: 5 g
o Procedure:
- Dissolve 10 g potassium
iodide in 100 ml of distilled
water.
- Slowly add 5 g iodine
crystals, while shaking.
- Filter and store in a tightly
stoppered brown bottle.
IODINE SOLUTION:
o Normally form of iodine with
less mass of KI.
o reduces thyroid hormone and
can kill fungus, bacteria, and
other microorganisms such as
amoebas.
o Iodine deficiency and the
resulting low levels of thyroid
hormone can cause women to
stop ovulating, leading
to infertility.
o Preparation:
- 3g iodine crystals
- 6g potassium iodide
o Procedure:
- Dissolve potassium iodide
in about 200 cm3 distilled
water and then add iodine
crystals.
- Make the solution up to 1
litre with distilled water.
4. Describe structure of protein.
o Proteins are large biomolecules, or macromolecules, consisting of one or more
long chains of amino acid residues.
o Approximately from 2-50  amino acids residues.
o There are 20 common amino acids to form proteins.
o The monomer of protein is (CO-NH)
5. How would you prepare 100 ml of 0.5% CuSO4 solution from
CuSO4.5H2O (MW = 250)?
o
o
o
o
o
This is 0.5g of CuSO4
Molar mass of CuSO4: 160 g/mol
Molar mass of CuSO4.5H2O: 250 g/mol.
To weigh out 0.5g of CuSO4.5H2O we have: 0.5x250:160= 0.78grams
Weigh out 0.78grams of CuSO4.5H2O then dissolve it in water. Make up a volume
of 100ml in a volumetric flask.
6. Where can we find lipid in plant cells and animal cells?
o Plant cells: plasma membrane and vacuoles.
o Animal cells: many places.
7. Describe structure of nucleic acid.
o There are two nucleic acids in our body. one is DNA (deoxyribonucleic acid) and
RNA(ribonucleic acid). Both contain a tri-phosphate group attached to the ring
structure of a ribosesugar that's then attached to a nucleoside. this is the basic
structure of a nucleic acid, Now, “ A.DNA is a double stranded molecule that forms a
double helical structure. RNA is a single stranded molecule that can take a variety of
shapes. The difference between the two nucleic acids also lie on their ribose sugar
backbone.
8. In the forthcoming practical session, you will have to use a number of
different chemical solutions: Lugol solution, concentrated HCl, NaOH,
CuSO4, Soudan III, 20% Ethanol and glycerin. List three solutions,
which are most potentially toxic and thus require caution while
handling, in your opinion. Explain your reason.
o Three solution are most potentially toxic and thus require caution while handling is
concentrated HCl, Soudan III. Because HCl is the strong acid; and Soudan III is a
toxic with red color, it can go to the body through food, drink,…
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