13. 3. hydrogen bond เป็นพันธะที่ไม่แข็ง
แรงนัก เกิดกับ H ที่ต่อด้วย covalent bond
กับอะตอมของธาตุที่ดึงดูด electron ได้ดี
เช่น N หรือ O โดย electron ในพันธะ
นั้น จะดึงดูดไปใกล้ N หรือ O มากจนทำาให้
H เกิดเป็นประจุ + ทำาให้สามารถดึงดูดกับ
อะตอม
อื่นที่มี electron มาก เช่น O หรือ N
15. Human chemistry only a few elements are
important. Here, the most abundant element
s in biological systems are shown in red,
lesser elements in blue, and 'trace' elements
in green
http://www.chem.ufl.edu/~itl/2045/lectures/lec_2.html
34. 1) Monosaccharides (simple sugars)
These molecules consist of open-chain or ring forms of 3 to
8 carbon atoms. The most common type of
monosaccharide is the simple sugar "glucose".
http://io.uwinnipeg.ca/~simmons/1115/cm1503/carbohydrates.htm
37. - Glucose is an important energy source in
metabolically active cells.
- Fructose is a common sugar in fruit), and
- Galactose is the sugar found in milk
- Sugars with 6 carbons are called
"hexoses". 5 carbon sugars are "pentoses"
. Whereas 7 carbon sugars are called "hept
oses".
- Two very important "pentoses" (5 carbons)
are, Ribose found in Ribonucleic Acid, RNA,
and Deoxyribose found in Deoxyribonucleic
Acid, DNA.
42. Disaccharides
When two monosaccharides are joined
together they form a "disaccharide".
This linking of two sugars involves the
removal of a molecule of H2O (water) and is
therefore called a "dehydration linkage". T
he reaction is called "dehydration
synthesis".
e.g. Glucose + Glucose = Maltose
Glucose + Fructose = Sucrose
Glucose + Galactose = Lactose
43. This forms a bond between the #1 carbon of
one glucose and the #4 carbon of the other,
therefore it is called an 1-4 linkage, (or
Glycosidic Linkage).
http://io.uwinnipeg.ca/~simmons/1115/cm1503/carbohydrates.htm
47. Polysaccharides
These are long chains of monosaccharides
linked together by dehydration linkages.
http://io.uwinnipeg.ca/~simmons/1115/cm1503/carbohydrates.htm
49. The simplest polysaccharide is a long
chain (polymer) of glucose, called "starch".
http://io.uwinnipeg.ca/~simmons/1115/cm1503/carbohydrates.htm
50. There are 3 types of starch :
(1) Amylose : a non-branching straight chain of
glucose - used to store glucose in plants.
(2) Amylopectin : a branched chain, also used to
store glucose in plants.
(3) Glycogen : another branched chain molecule u
sed to store glucose in animals.
Polysaccharides can also form very important stru
ctural components in plants and animals.
Cellulose: is the principal constituent in plant c
ell walls.
51. This macromolecule is a long chain of
glucose subunits held together by (1-4) lin
kages. (Not (1-4) as in starch!)
http://io.uwinnipeg.ca/~simmons/1115/cm1503/carbohydrates.htm
52. Chitin : is an important structural material
in the outer coverings of insects, crabs, and
lobsters. In chitin the basic subunit is not
glucose (but N-acetyl-D-glucoseamine) in 1-4 li
nkages. These polymers are made very hard w
hen impregnated with calcium carbonate.
60. Amino acid there is
a -COOH, which is a carboxyl group (acidic).
a -NH2, which is an amino group (basic).
an -H hydrogen.
a residue R which varies depending on the
amino acid.
62. peptide bond
Two amino acids can, under some
circumstances, react together. The result is the creat
ion of a dipeptide. A molecule of water is released in
the process. This is the basic reaction involved in the
synthesis of proteins.
67. - Each amino acid contains an "amine" group
(NH3) and a "carboxy" group (COOH) (shown in
black in the diagram).
- The amino acids vary in their side chains
(indicated in blue in the diagram).
- The eight amino acids in the orange area are non
polar and hydrophobic.
- The other amino acids are polar and hydrophilic (
"water loving").
- The two amino acids in the magenta box are acid
ic ("carboxy" group in the side chain).
- The three amino acids in the light blue box are ba
sic ("amine" group in the side chain).
68.
69.
70.
71.
72.
73. These are very large 3 dimensional
macromolecules.
They are very important as structural
molecules in the cell, as energy sources,
and most importantly as "enzymes",
(protein catalysts which speed up chemical r
eactions in the cell without the need for high
temperature or drastic pH changes).
Proteins are often called "polypeptides" be
cause they are made of long chains of buildi
ng blocks called "amino acids".
75. Structure of Proteins
"The sequence of amino acids in the polypeptide
chain."
http://io.uwinnipeg.ca/~simmons/1115/cm1503/proteins.htm
76. The "peptide" bond. To form a "dipeptide"
molecule.
Therefore the primary structure is the sequence of
amino acids.
http://io.uwinnipeg.ca/~simmons/1115/cm1503/proteins.htm
77. Secondary Level of Organization of
Polypeptides
http://io.uwinnipeg.ca/~simmons/1115/cm1503/proteins.htm
78. The Tertiary Structure of
Proteins
http://io.uwinnipeg.ca/~simmons/1115/cm1503/proteins.htm
79. Quaternary Structure of Proteins
Hemoglobin: an oxygen carrying protein in red
blood cells which is made of 4 parts.
http://io.uwinnipeg.ca/~simmons/1115/cm1503/proteins.htm
82. Proteins when heated can unfold or "Denature".
This loss of three dimensional shape will usually be accom
panied by a loss of the proteins function. If the denatured p
rotein is allowed to cool it will usually refold back into it’s or
iginal conformation.
http://io.uwinnipeg.ca/~simmons/1115/cm1503/proteins.htm
94. Saturated and Unsaturated Fatty Acids
Saturated Fatty Acid : These are fatty acids
which contain the maximum possible number of
hydrogen atoms. That is each carbon in the chain
has two hydrogen atoms attached to it. It is "satura
ted" with hydrogen atoms.
Unsaturated Fatty Acid : These are fatty acids w
hich contain carbon-to-carbon "double" bonds. The
refore since a carbon atom can have only 4 covale
nt bonds, there is one less bond available for hydr
ogen, therefore there is one less hydrogen. (The c
arbons are not "saturated" with hydrogen atoms.)
108. What are Omega-3 and Omega-6
fatty acids?
Omega-3 (ω3) and omega-6 (ω6) fatty acids
are unsaturated "Essential Fatty Acids" (EFA
s) that need to be included in the diet
because the human metabolism cannot crea
te them from other fatty acids. Since these fa
tty acids are polyunsaturated, the terms n-3
PUFAs and n-6 PUFAs are applied to omeg
a-3 and omega-6 fatty acids, respectively.
109. Saturated and Unsaturated Fatty Acids
Saturated Fatty Acid: These are fatty acids
which contain the maximum possible number of
hydrogen atoms. That is each carbon in the chain
has two hydrogen atoms attached to it. It is "satura
ted" with hydrogen atoms.
Unsaturated Fatty Acid: These are fatty acids whi
ch contain carbon-to-carbon "double" bonds. Ther
efore since a carbon atom can have only 4 covalen
t bonds, there is one less bond available for hydro
gen, therefore there is one less hydrogen. (The car
bons are not "saturated" with hydrogen atoms.)
117. The Triglycerides
Both fats and oils are "triglycerides".
These molecules are made up of 3 long chai
n "fatty acids" attached to a 3 carbon
molecule called "glycerol".
The carboxyl and the fatty acids are attache
d to the -OH groups of the Glycerol via a "de
hydration synthesis" reaction to yield an "est
er" bond.
Function: storage of energy - "fat" in
animals, and "oils" in plants.
120. Phospholipids
• Since water is also a polar molecule the
polar end of the phospholipid is "attracted"
to the + ends of the water molecules.
• It is said to be "hydrophillic" (or water
loving).
• While the neutral end of the phospholipid
molecule is non-polar, i.e. is repelled by
the "polar" water molecules, it is said to be
"hydrophobic" (water fearing).
124. This duel nature of the phospholipid
molecule makes it very useful as a component
of cell membranes.
http://io.uwinnipeg.ca/~simmons/1115/cm1503/lipids.htm
134. Nucleic Acids
• Nucleic Acids are macromolecular
structures which store and express all the
information necessary for building and mai
ntaining life.
• DNA (DeoxyriboNucleic Acid) is
considered as the repository of the genetic
information.
• RNAs (RiboNucleic Acids) may be
regarded as vectors and translators of the
information
135. Nucleoside = base + sugar
Nucleotide = base + sugar
+ phosphate
group
137. Nucleotides
• Nucleotides : monomers of nucleic
acids.
• All nucleic acids consist of many
nucleotides bonded together.
• 1. Sugar: 5-carbon (Pentose)
• 2. Phosphate group
• 3. Nitrogen base
138. 1. Sugar: 5-carbon (Pentose)
• Note the absence and presence of the hydroxyl (-OH) group on the 2’
carbon in the sugars from DNA and RNA, respectively
142. A Nucleotide consists of :
• a nitrogenous base: purine (Adenine (A)
or Guanine (G)) or pyrimidine (Cytosine
(C) or Thymine (T) (or Uracil (U)in RNA).
• a sugar : Deoxyribose (DNA) or Ribose
(RNA).
• a phosphate group
