2.1 Molecules to Metabolism

Question 1

What does molecular biology explain?

Answer 1

Living processes in terms of the chemical substances involved and how they interact with each other.

Question 2

What molecules are most varied?

Answer 2

Neucleic acids, which are used to make genes, and proteins, which perform a huge range of tasks within the cell.

Question 3

What is the relationship that is at the heart of molecular biology?

Answer 3

The relationship between genes and proteins.

Question 4

What is vitalism? How did Friedrich Wohler disprove it?

Answer 4

-Vitalism was a doctrine which ascribed the origin, phenomena, and functions of life to a ‘vital principle’ distinct from chemical and physical forces. -Wohler synthesized urea. This was the first time an organic compound was synthesized artificially, without the supposed ‘vital principle’ involved. This led to other chemists synthesizing organic compounds, which in turn led to the abandonment of vitalism.

Question 5

Describe the structure of ribose.

Answer 5

-C5H10O5 -Five-membered ring with a side chain -Four carbon atoms are in the ring and one forms the side chain -Carbon atoms can be numbered, staring with number 1 on the right -The hydroxyl groups on the carbon atoms 1, 2, 3, point up, down, down respectively.

Question 6

Describe the structure of glucose.

Answer 6

• C6H12O6
• Six-membered ring with a side chain
• Five carbon atom are in the ring and one forms the side chain
• The hydroxyl groups on carbon atoms 1, 2, 3, 4, point down, down, up, down respectivley.

Question 7

What are some characteristics of lipids? What are some examples?

Answer 7

• Insoluble in water and hydrophobic macromolecules
• Steroids, waxes, fatty acids, and triglycerides are examples

Question 8

Describe the structure of a saturated fatty acid. What is the simplified molecular diagram for a saturated fatty acid?

Answer 8

-At one end of the chain is a carboxyl group which combines with a chain of saturated carbon atoms.

CH3-[CH2}n-COOH

Question 9

What are amino acids comprised of?

Answer 9

All amino acids contain C, H, O, and N. Two also contain S.

Question 10

Describe the structure of the amino acid. What is its generalized molecular diagram?

Answer 10

A carbon atom bonded to an amine group to its left, a carboxyl to its right, and a variable R group.

H2N-CRH-COOH

Question 11

What are nucleic acids? What are the two types?

Answer 11

• A chain of subunits called nucleotides, which contain carbon, hydrogen, oxygen, nitrogen, and phosphorus.
• RNA (ribonucleic acid) and DNA (deoxyribonucleic acid)

Question 12

Define metabolism.

Answer 12

The sum of all reactions that occur in an organism. It consists of pathways by which one type of molecule is transformed into another.

Question 13

What are the two types of metabolic pathways?

Answer 13

• Catabolic pathway: Breakdown of complex molecules into simpler molecules. Release energy. Hydrolysis reactions.
• Anabolic pathway: Synthesis of complex molecules from simpler ones. Require energy, usually ATP. Condensation reactions.

Question 14

What are examples of anabolic processes? Catabolic processes?

Answer 14

• Anabolic: Protein synthesis using ribosomes, DNA synthesis during replication, photosynthesis.
• Catabolic: Food digestion, cellular respiration.