Biological Molecules - You Are What You Eat (Chemistry)

Crash Course: Biological Molecules - You Are What You Eat (Chemistry)

You Are What You Eat: The Chemistry of Biological Molecules

Introduction Did you know that the human body is made up of approximately 60 trillion cells, each containing trillions of molecules? That's a whole lotta chemistry going on inside you!

The Core Idea Biological molecules are the building blocks of life, and understanding their chemistry is crucial for grasping how our bodies work. Think of it like a recipe book – if you know the ingredients and how they interact, you can whip up a mean human (or at least, a decent sandwich).

Key Facts & Figures

• DNA was discovered in 1869 by Friedrich Miescher, a Swiss physician who isolated the molecule from white blood cells.
• The structure of DNA was revealed in 1953 by James Watson and Francis Crick, who used X-ray crystallography to determine its double helix shape.
• Proteins are made up of 20 different amino acids, which are linked together in long chains to form polypeptides.
• Carbohydrates are composed of carbon, hydrogen, and oxygen, with the general formula (CH2O)n.
• Fats are triglycerides, made up of three fatty acid chains attached to a glycerol molecule.
• The human body contains approximately 37.2 trillion neurons, each connected to thousands of other neurons through synapses.
• The largest molecule in the human body is the protein titin, which is found in muscle cells and has a molecular weight of over 3,000,000 Da.
• The smallest molecule in the human body is the oxygen molecule (O2), which is essential for cellular respiration.
• The human body produces approximately 2 liters of saliva per day, which contains enzymes that break down carbohydrates.
• The largest organ in the human body is the skin, which covers an area of approximately 22 square feet (2 square meters).
• The human brain uses approximately 20% of the body's energy expenditure, despite accounting for only 2% of its mass.

Thought Bubble

Imagine you're a chef in a bustling kitchen, whipping up a batch of your famous chicken parmesan. You've got your ingredients laid out: juicy chicken breasts, crispy breadcrumbs, melted mozzarella cheese, and a tangy marinara sauce. As you cook, you're not just combining flavors – you're also creating a complex network of biological molecules that will ultimately become the dish.

First, you season the chicken with salt, pepper, and herbs, which are all made up of tiny molecules that interact with each other and with the chicken's proteins. As the chicken cooks, the proteins denature and reorganize into new structures, creating a tender and juicy texture.

Next, you coat the chicken in breadcrumbs, which are made up of carbohydrates that will provide a crunchy exterior. The breadcrumbs also contain enzymes that will break down the starches in the chicken, making it easier to digest.

Finally, you top the chicken with melted mozzarella cheese, which is a protein-based molecule that will melt and bind to the chicken's proteins, creating a creamy and indulgent sauce.

Why This Matters

• Understanding biological molecules is crucial for developing new medicines, which can target specific molecules to treat diseases.
• The chemistry of biological molecules has led to major advances in agriculture, allowing us to breed crops that are more resilient and productive.
• Biological molecules play a key role in climate change, as they are involved in the carbon cycle and the release of greenhouse gases.
• The study of biological molecules has led to a greater understanding of evolution, as we can see how molecules have changed over time to adapt to their environments.
• Biological molecules are essential for space exploration, as they provide a source of food and energy for astronauts on long-duration missions.
• The chemistry of biological molecules has led to major advances in biotechnology, allowing us to engineer new organisms and products.

Crash Course Recap

• Biological molecules are the building blocks of life, and understanding their chemistry is crucial for grasping how our bodies work.
• DNA was discovered in 1869 by Friedrich Miescher, and its structure was revealed in 1953 by James Watson and Francis Crick.
• Proteins are made up of 20 different amino acids, which are linked together in long chains to form polypeptides.
• Carbohydrates are composed of carbon, hydrogen, and oxygen, with the general formula (CH2O)n.
• Fats are triglycerides, made up of three fatty acid chains attached to a glycerol molecule.
• The human body contains approximately 37.2 trillion neurons, each connected to thousands of other neurons through synapses.
• The largest molecule in the human body is the protein titin, which is found in muscle cells and has a molecular weight of over 3,000,000 Da.
• The smallest molecule in the human body is the oxygen molecule (O2), which is essential for cellular respiration.
• The human body produces approximately 2 liters of saliva per day, which contains enzymes that break down carbohydrates.
• The largest organ in the human body is the skin, which covers an area of approximately 22 square feet (2 square meters).
• The human brain uses approximately 20% of the body's energy expenditure, despite accounting for only 2% of its mass. ⚠️ The human body is made up of approximately 60 trillion cells, each containing trillions of molecules. ⚠️ The structure of DNA is a double helix, with two complementary strands of nucleotides twisted together.

Quiz Yourself

1. What is the general formula for carbohydrates? a) (CH2O)n b) (CH2O)2 c) (CH2O)3 d) (CH2O)4

Answer: a) (CH2O)n

1. What is the largest molecule in the human body? a) Titin b) DNA c) Proteins d) Fats

Answer: a) Titin

1. What is the smallest molecule in the human body? a) Oxygen molecule (O2) b) Carbon dioxide (CO2) c) Nitrogen molecule (N2) d) Water molecule (H2O)

Answer: a) Oxygen molecule (O2)

1. What is the approximate number of neurons in the human brain? a) 10 billion b) 20 billion c) 37.2 trillion d) 100 trillion

Answer: c) 37.2 trillion

1. What is the approximate percentage of the body's energy expenditure used by the brain? a) 5% b) 10% c) 20% d) 30%

Answer: c) 20%