Related Concept Videos

Dietary Connections01:23

Dietary Connections

In biological systems, most metabolic pathways are interconnected. The cellular respiration processes that convert glucose to ATP—such as glycolysis, pyruvate oxidation, and the citric acid cycle—tie into those that break down other organic compounds. As a result, various foods—from apples to cheese to guacamole—end up as ATP. In addition to carbohydrates, food also contains proteins and lipids—such as cholesterol and fats. All of these organic compounds are used as energy sources to produce...
Proteins: Dietary Sources and Requirements01:28

Proteins: Dietary Sources and Requirements

Consuming animal-based products offers high-quality proteins that contain optimal levels and combinations of essential amino acids, crucial for tissue repair and growth. Foods like eggs, milk, fish, and most meats are a source of complete proteins. Legumes and cereals are abundant in proteins; however, they typically lack a full range of essential amino acids. As a result, they are considered incomplete protein sources. Some plant sources like soybeans, quinoa, and amaranth do contain complete...
Energy Balance01:19

Energy Balance

The human body gets energy from the three macronutrients: carbohydrates, proteins, and fats. Energy is released when the chemical bonds in the organic compounds present in the food are broken down. The energy content of food is measured in kilocalories (kcal), defined as the amount of heat required to raise the temperature of one kilogram of water by one degree Celsius. This value is determined by measuring the temperature change of the water surrounding a calorimeter after the complete...
Protein Digestion01:02

Protein Digestion

Protein digestion begins in the stomach, where the highly acidic environment can easily disrupt protein structure by exposing the peptide bonds of polypeptide chains. After polypeptide chains are broken into individual amino acids by a series of digestive enzymes, the amino acids are transported to the liver via the bloodstream to produce energy.
Key Elements for Plant Nutrition02:35

Key Elements for Plant Nutrition

Like all living organisms, plants require organic and inorganic nutrients to survive, reproduce, grow and maintain homeostasis. To identify nutrients that are essential for plant functioning, researchers have leveraged a technique called hydroponics. In hydroponic culture systems, plants are grown—without soil—in water-based solutions containing nutrients. At least 17 nutrients have been identified as essential elements required by plants. Plants acquire these elements from the atmosphere, the...