Molecular Biology

i. Molecular biology explains living processes in terms of the chemical substances involved.
• How molecules interact?
• Important molecules include: water, carbs, lipids, proteins, nucleic acids.
• Relationship between genes and proteins???
• Look at each part but when put parts together, are their any emergent properties.

ii. Carbon atoms can form four covalent bonds allowing a diversity of stable compounds to exist.
• Form up to 4 covalent bonds
• Has 4 valence electrons in its outer shell
• Can form single, double, even triple bonds.
• Carbon is basic building block of life!

Draw a Carbon Atom:
Hint: Carbon has 6 protons and 6 electrons
Label everything!

Carbon has 4 valence electrons: label the single and double bonds below and annotate.

iii. Life is based on carbon compounds including carbohydrates, lipids, proteins, and nucleic acids.
• Carbohydrates:

iii. Life is based on carbon compounds including carbohydrates, lipids, proteins, and nucleic acids.
• Lipids:

iii. Life is based on carbon compounds including carbohydrates, lipids, proteins, and nucleic acids.
• Proteins:

iii. Life is based on carbon compounds including carbohydrates, lipids, proteins, and nucleic acids.
• Nucleic Acids:

*Alpha D glucose –”A town down”. Get that OH group down.
*Beta D glucose- “betas are best”. Get that OH group up!!

Label as saturated or unsaturated.

Skills: Identification of biochemical such as sugars.
Notice all composed of C,H, and O. One ring are monosaccharide, two ring are disaccharide, polysaccharides are composed of many monosacharrides joined together.
Each has hydroxyl group connected to ring.

Skills: Identification of biochemical such as lipids.
Notice: Saturated fatty acid has no double bonds but unsaturated does.
Triglyceride has three chains coming off backbone, phospholipids has two chains coming of backbone that contains phosphate molecule, steroids composed of C, H, and O with many rings connected together.

1.
2.

Triglyceride, phospholipid, or steroid????
How did you know?

Triglyceride, phospholipid, or steroid????
How did you know?

Triglyceride, phospholipid, or steroid????
How did you know?

Triglyceride, phospholipid, or steroid????
How did you know?

Triglyceride, phospholipid, or steroid????
How did you know?

Skills: Identification of biochemical such as amino acids.
Notice: contains elements C, H, O, and N. At one end it has carboxyl group.

QUIZ: Identification of biochemicals such as sugars, lipids or amino acids from molecular diagrams.

QUIZ: Identification of biochemicals such as sugars, lipids or amino acids from molecular diagrams.

QUIZ: Identification of biochemicals such as sugars, lipids or amino acids from molecular diagrams.

iv. Metabolism is the web of all the enzymecatalyzed reactions in a cell or organism
• All the chemical reactions in a cell
• Needed to grow, reproduce, maintain.

v. Anabolism is the synthesis of complex molecules from simpler molecules including the formation of macromolecules from monomers by condensation reactions.
• BUILDING of large molecules
• Can you give an example?

vi. Catabolism is the breakdown of complex molecules into simpler molecules including the hydrolysis of macromolecules into monomers.
• BREAKING DOWN of large molecules
• Can you give an example?

Examples of anabolism by condensation
Maltose synthase condenses two molecules of glucose into maltose forming a glycosidic bond
A ribosome condenses two amino acids into a dipeptide forming a peptide bond
The bonds formed are types of covalent bonds
.
Bonding monomers together creates a polymer (mono = one, poly = many) http://commons.wikimedia.org/wiki/File:Peptidformationball.svg

Examples of catabolism by hydrolysis
A protease hydrolyses a dipeptide into two amino acids breaking the peptide bond
Lactase hydrolyses
Lactose into Glucose and Galactose breaking the glycosidic bond http://commons.wikimedia.org/wiki/File:Lactose_hydrolysis.svg
http://commons.wikimedia.org/wiki/File:Amino_acid4.png

WS: Drawing molecules

Classifying molecules (group activity)

Application: Urea as an example of a compound that is produced by living organisms but can also be artificially synthesized.
• What is Vitalism?
• Vitalism is the theory that the origin and phenomena of life are dependent on a force or principle distinct from purely physicochemical forces and, consequently, organic materials cannot be synthesized from inorganic components. This theory was widely believed until the nineteenth century.

Application: Urea as an example of a compound that is produced by living organisms but can also be artificially synthesized.
• Video on how the synthesis of urea was discovered (2.3 minutes) http://science.howstuffworks.com/life/27866-100greatest-discoveries-synthesis-of-urea-vdeo.htm
• https://www.youtube.com/watch?v=YNmfSHSq_HY
• How did the synthesis of urea contribute to the falsification of vitalism?

The synthesis of urea did not cause all biologists to abandon vitalism immediately.
In 1858, Pasteur showed that fermentation only occurs when living cells are present and, that fermentation only occurs in the absence of oxygen concluding that fermentation was a "vital action".
However, Berzelius and others biologists then claimed that fermentation resulted from chemical agents or catalysticts within cells.
And nowadays...
Vitalism has been rejected both scientifically and philosophically, and nowadays it is often used as pejorative epithet. However, it is still impossible to synthesize some complex organic compounds
(such as hemoglobin) artificially. Despite this, biologists now unanimously recognize that living organisms are ruled by the same chemicophisical forces as non-living matter is.

• Describe what is vitalism and how did the synthesis of urea contribute tot its falsification.