Molecules to Metabolism II

Review

In the previous Powerpoint we looked at◦The elements in living organisms◦The importance of carbon◦The major molecules of life

Carbohydrates Lipids Proteins Nucleic Acids

Nucleic Acids

Uses: Hereditary material (DNA, RNA)◦High Energy Source (ATP)◦Cellular Messenger (cAMP)◦Co-enzyme involved in production of ATP(NADH)

◦ Structure: Made up of nucleotides (monomer) Each nucleotide is made up of a sugar, a phosphate and a nitrogen containing base (purine or pyrimidine)

Structure of a Nucleotide

A single nucleotide looks like this

DNA Structure

Two long strands of nucleotides then combine together to form something that looks like a twisting ladder

(called a double helix)

DNA Structure

There are 4 different bases1. Adenine 2. Thymine

3. Guanine 4. Cytosine

DNA Structure

Adenine only joins with Thymine

Cytosine only joins with Guanine

DNA Structure

The only thing that makes a living organism’s DNA unique is the sequence of bases in the chain

What is Metabolism?

Metabolism is the sum of all chemical reactions that occur in the body

There are two types of metabolic reactions:

Anabolic & Catabolic

Anabolic Reactions

Anabolic reactions build large molecules from smaller ones

This usually requires (uses) energy

Example: Photosynthesis◦CO2 + H2O C6H12O6 + O2

◦Source of Energy: Sunlight!

Condensation/Dehydration Synthesis

Anabolic reactions often use a process called condensation or dehydration synthesis to link small molecules together

This process takes H from one molecule and OH from the other forming a molecule of water

Catabolic Reactions

Catabolic reactions break large molecules down into smaller ones

They usually release energy

Example: Cellular Respiration C6H12O6 + O2 H2O + CO2

◦Energy released is used to make ATP!

Hydrolysis

Catabolic reactions use a process called hydrolysis to split large molecules into small ones

H2O is used to “cut” the large moleculeIt is the exact opposite of condensation

Questions

1. What are the four most abundant elements in our bodies?2. List the elements that make up

◦ Carbohydrates◦ Lipids◦ Proteins◦ Nucleic acids

3. Draw a structural formula for Glucose4. Draw a structural formula for an amino acid5. Draw a structural formula for an adenine nucleotide6. Draw a structural formula for an 8 carbon saturated fatty acid7. Draw a structural formula for a 6 carbon mono-unsaturated fatty acid8. Show how condensation links two amino acids together9. Show how hydrolysis can split lactose into glucose and galactose

Other Stuff

Be sure to read page 63 in your textbook about the synthesis of urea

Falsification is a term used to describe the process of disproving an accepted theory

What theory was falsified when Friedrich Wohler synthesized urea in a lab?