Module 1

Basics of biochem

What are the four major classes of biomolecules?

• Proteins

• Nucleic Acids

• Polysaccharides (carbohydrates)

• Lipids

Through what different perspectives can we analyze the living state?

• Chemical

• Energy

• Genetic

• Evolutionary

What are the most abundant atoms within organisms?

Carbon, Hydrogen and Oxygen

What makes life on Earth possible?

Water, made up of two hydrogen and one oxygen

All known life forms are ______-based.

All known life forms are carbon based

Why is carbon-based life forms more favorable?

• Very versatile in boding (stronger)

• Its combustion releases more energy (and CO2 and H2O)

• Soluble in water/ recyclable

What dictates the function for a biomolecule?

Its structure dictates its function

How do different functional groups affect biomolecules?

They determine their structure, functions and properties in biomolecules

Conformation

Moveable spatial arrangement of atoms within a molecule

The structure can be changed w/o breaking covalent bonds (usually single bonds)

Configuration

Fixed spatial arrangement of atoms within a molecule

The structure cannot be changed w/ o breaking covalent bonds

What are the different ways to affect configuration?

• Double bonds (geometric isomers)

• Chiral carbons

What re the two types of geometric isomers?

• CIs isomers: groups on the same side of a double bond

• Trans isomers: groups acroos from each other

Describe the structure and functions of proteins

Structure:

• long unbranched polymers of amino acids.

• folded amino acids into complex patterns

Function:

• receptors

• signal molecules

• enzymes/ catalysts

Describe the structure and functions of amino acids

Structure:

• linear polymers of nucleotides

• bases are linked by phosphodiester bonds

Function:

• store and transfer genetic information for cellular functions and interactions

Describe the structure and functions of lipids

Structure:

• hydrophilic head

• hydrophobic tails ( hydrocarbon chains )

Function:

• formation of membranes/ barriers

• energy storage (tails)

• signaling

Describe the structure and functions of carbohydrates

Structure:

• highly branched monosaccharide ( 6C) polymers

• animals-branched glycogen, plants-starch

Function:

• cell-cell recognition

• energy storage

• structural

Reasons why we need prokaryotic cells

Critical for our health:

• help digest food

• maintain a functional immune system

• impact on mental health, obesity and intelligence

In Vitro

Studying the behaviour of molecules in an isolated environment

In Vivo

Studying the behaviour of molecules within a living organism

Definition of free energy

G=H-TS

Where:

• g free energy (able to do work)

• h is the number and kind of bonds (enthalpy)

• s is the degree of randomness (entropy)

• t is temperature in Kelvin

What are the characteristics of a spontaneous reaction?

• Delta G is negative (final E is less than initial E)

• Release free energy

• Reaction is exergonic

What are the characteristics of a non-spontaneous reaction?

• Delta G is positive (final E is more than initial E)

• Needs input of free energy

• Reaction is endergonic

What is it mean when a system is at equilibrium?

Delta G=0. There is no change in free energy

How do cells drive thermodynamically unfavourable reactions?

Doing coupling reactions where the sum of all free energy is negative (spontaneous)

Where is the energy taken to form ATP?

Taken from sunlight or fuels

How does the energy extracted from ATM serve in biochemical processes?

The energy released from its breaking down and synthesis is the link between catabolic and anabolic reactions

Where is the information about cells stored?

In DNA which is a linear sequence of nucleic acids

What does DNA provide for different organisms?

• infos for the formation of other cellular processes

• template production of identical DNA molecules

Explain the central dogma of biochemistry

1. DNA replication: making DNA from DNA

2. Transcription: mRNA chain of a gene

3. RNA (language)

4. Translation: how mRNA goes to protein (language)

5. Protein: made from amino acids/polypeptides

What influences the protein’s biological activity?

The structure of the protein which is moreover dictated by the amino acid s