Organic Molecules and Biological Functions

The video covers topic 2.1 of the IB Biology Core Curriculum, focusing on molecules to metabolism. It explains the complexity of chemical reactions in living organisms, the central dogma of molecular biology, and the role of carbon in organic molecules. The video also details the major classes of organic molecules: carbohydrates, lipids, proteins, and nucleic acids. It discusses metabolism, including anabolism and catabolism, and the role of enzymes. Finally, it addresses the historical concept of vitalism and how the synthesis of urea challenged this idea.

What is the central dogma of molecular biology?

• Information flows from RNA to DNA to proteins.

• Information flows from DNA to RNA to proteins.

• Information flows from DNA to proteins to RNA.

• Information flows from proteins to RNA to DNA.

Why is carbon considered the backbone of organic molecules?

• It is the heaviest element in organic compounds.

• It can form four covalent bonds, allowing for diverse structures.

• It is the most abundant element in the universe.

• It can form ionic bonds with many elements.

Which of the following is NOT a function of proteins in living systems?

• Transporting molecules

• Acting as hormones

• Storing genetic information

• Serving as enzymes

What distinguishes lipids from other organic molecules?

• They are composed of nucleotides.

• They are polar and soluble in water.

• They contain nitrogen as a primary element.

• They are non-polar and insoluble in water.

What is the role of enzymes in metabolic pathways?

• They are consumed in the reactions they catalyze.

• They are only involved in catabolic reactions.

• They act as catalysts to speed up reactions.

• They slow down chemical reactions.

Which of the following is a characteristic of nucleic acids?

• They contain carbon, hydrogen, oxygen, nitrogen, and phosphorus.

• They are composed of amino acids.

• They are insoluble in water.

• They are primarily used for energy storage.

What is the primary structural difference between glucose and fructose?

• Glucose has a six-carbon ring, while fructose has a five-carbon ring.

• Glucose and fructose have the same structure.

• Glucose has a five-carbon ring, while fructose has a six-carbon ring.

• Glucose and fructose are not isomers.

What is the primary difference between anabolism and catabolism?

• Anabolism builds molecules, while catabolism breaks them down.

• Anabolism breaks down molecules, while catabolism builds them.

• Both anabolism and catabolism break down molecules.

• Both anabolism and catabolism build molecules.

Which process involves the removal of a water molecule to join two monomers?

• Hydrolysis

• Condensation

• Oxidation

• Reduction

What was the significance of Friedrich Wöhler's experiment?

• It proved that only living organisms can produce organic compounds.

• It demonstrated that organic compounds can be synthesized in a lab.

• It showed that urea is only produced by the kidneys.

• It confirmed the theory of vitalism.