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Chemistry of the Cell02:58

Chemistry of the Cell

The cell is chemically composed of water, organic molecules and inorganic ions.
Water
The polarity of the water molecule and its resulting hydrogen bonding makes water a unique substance with special properties that are intimately tied to the processes of life. Life originally evolved in an aqueous environment, and most of an organism’s cellular chemistry and metabolism occur inside the aqueous contents of the cell’s cytoplasm. Special properties of water are its high heat capacity and heat of...
Chemistry of the Cell02:58

Chemistry of the Cell

The cell is chemically composed of water, organic molecules and inorganic ions.
Water
The polarity of the water molecule and its resulting hydrogen bonding makes water a unique substance with special properties that are intimately tied to the processes of life. Life originally evolved in an aqueous environment, and most of an organism’s cellular chemistry and metabolism occur inside the aqueous contents of the cell’s cytoplasm. Special properties of water are its high heat capacity and heat of...
Introduction to Enzymes01:22

Introduction to Enzymes

The use of enzymes by humans dates to 7000 BCE. Humans first used enzymes to ferment sugars and produce alcohol without knowing that this was an enzyme-catalyzed reaction. Wilhelm Kuhne coined the term 'enzyme' in 1877 from the Greek words ‘en’ meaning ‘in’ or ‘within’ and ‘zyme’ meaning ‘yeast.’
Most enzymes are proteins that speed up biochemical reactions without being consumed. Enzymes contain one or more active sites that bind the substrates and convert them into products. Many enzymes also...
Introduction To Enzymes01:22

Introduction To Enzymes

The use of enzymes by humans dates to 7000 BCE. Humans first used enzymes to ferment sugars and produce alcohol without knowing that this was an enzyme-catalyzed reaction. Wilhelm Kuhne coined the term 'enzyme' in 1877 from the Greek words ‘en’ meaning ‘in’ or ‘within’ and ‘zyme’ meaning ‘yeast.’
Most enzymes are proteins that speed up biochemical reactions without being consumed. Enzymes contain one or more active sites that bind the substrates and convert them into products. Many enzymes also...
Enzyme-linked Receptors01:00

Enzyme-linked Receptors

Enzyme-linked receptors are proteins that act as both receptor and enzyme, activating multiple intracellular signals. This is a large group of receptors that include the receptor tyrosine kinase (RTK) family. Many growth factors and hormones bind to and activate the RTKs.
Neurotrophin (NT) receptors are a family of RTKs, including trkA, trkB, and trkC (tropomyosin-related kinase) receptors. TrkA is specific for nerve growth factor (NGF), neurotrophin-6, and neurotrophin-7. TrkB binds...
Chemistry of Carbohydrates03:25

Chemistry of Carbohydrates

Carbohydrates are an essential part of the diet in humans and animals. Grains, fruits, and vegetables are natural sources of carbohydrates that provide energy to the body, particularly through glucose, a simple sugar that is a component of starch and an ingredient in many staple foods. The stoichiometric formula (CH2O)n, where n is the number of carbons in the molecule represents carbohydrates. In other words, the ratio of carbon to hydrogen to oxygen is 1:2:1 in carbohydrate molecules. This...