All life is composed mainly of the four macromolecule building blocks : carbohydrates, lipids, proteins, and nucleic acids. The interactions of different polymers of these basic molecule types make up the majority of life's structure and function. Also, why is carbon so important? Carbon is the basic building block of life. This is the reason carbon dating is effective, all living organisms contain carbon.
Also, carbon is so important to life because virtually all molecules in the body contain carbon. For this reason it can form long chain molecules, each with different properties. Carbon dioxide is actually the main fertilizer and building block for life. Life on Earth is based on carbon , likely because each carbon atom can form bonds with up to four other atoms simultaneously.
This quality makes carbon well-suited to form the long chains of molecules that serve as the basis for life as we know it, such as proteins and DNA. Carbon is the universal building block for life as we know it. Its ability to form complex, stable molecules with itself and other elements, particularly hydrogen, oxygen, and nitrogen is unique.
Alkanes are con- verted to other compounds by replacing a hydrogen with other functional groups. What is the smallest unit of life? What is life made up of? From the mightiest blue whale to the most miniscule paramecium, life as we know it takes dramatically different forms. Nonetheless, all organisms are built from the same six essential elemental ingredients: carbon, hydrogen, nitrogen, oxygen, phosphorus and sulfur CHNOPS. Why those elements? What is the basic building block?
What are the building blocks of nature? The building blocks Our everyday world is made of just three of these building blocks: the up quark, the down quark and the electron. This set of particles is all that's needed to make protons and neutrons and to form atoms and molecules. Are amino acids the building blocks of life?
Amino acids are the building blocks for life on earth. They may originate in space and reach the earth via comets and meteorites. Amino acids form the basis for proteins, and are an essential element of all life on earth. What do cells do? Cells are the basic building blocks of all living things. When some of these bonds are in the cis configuration, the resulting bend in the carbon backbone of the chain means that triglyceride molecules cannot pack tightly, so they remain liquid oil at room temperature.
On the other hand, triglycerides with trans double bonds popularly called trans fats , have relatively linear fatty acids that are able to pack tightly together at room temperature and form solid fats. In the human diet, trans fats are linked to an increased risk of cardiovascular disease, so many food manufacturers have reduced or eliminated their use in recent years. In contrast to unsaturated fats, triglycerides without double bonds between carbon atoms are called saturated fats, meaning that they contain all the hydrogen atoms available.
Saturated fats are a solid at room temperature and usually of animal origin. Enantiomers share the same chemical structure and bonds but differ in the placement of atoms such that they are mirror images of each other.
Stereoisomers are a type of isomer where the order of the atoms in the two molecules is the same but their arrangement in space is different. Optical isomers are stereoisomers formed when asymmetric centers are present; for example, a carbon with four different groups bonded to it. Enantiomers are two optical isomers i. Every stereocenter in one isomer has the opposite configuration in the other.
Compounds that are enantiomers of each other have the same physical properties except for the direction in which they rotate polarized light and how they interact with different optical isomers of other compounds. The amino acid alanine is example of an entantiomer. The two structures, D-alanine and L-alanine, are non-superimposable. In nature, only the L-forms of amino acids are used to make proteins. Some D forms of amino acids are seen in the cell walls of bacteria, but never in their proteins.
Similarly, the D-form of glucose is the main product of photosynthesis and the L-form of the molecule is rarely seen in nature. Enantiomers : D-alanine and L-alanine are examples of enantiomers or mirror images.
Only the L-forms of amino acids are used to make proteins. Organic compounds that contain a chiral carbon usually have two non-superposable structures. These two structures are mirror images of each other and are, thus, commonly called enantiomorphs; hence, this structural property is now commonly referred to as enantiomerism. Enantiopure compounds refer to samples having, within the limits of detection, molecules of only one chirality. Enantiomers of each other often show different chemical reactions with other substances that are also enantiomers.
Since many molecules in the bodies of living beings are enantiomers themselves, there is sometimes a marked difference in the effects of two enantiomers on living beings. Functional groups are groups of molecules attached to organic molecules and give them specific identities or functions. Functional groups are groups of atoms that occur within organic molecules and confer specific chemical properties to those molecules.
Molecules with other elements in their carbon backbone are substituted hydrocarbons. Each of the four types of macromolecules—proteins, lipids, carbohydrates, and nucleic acids—has its own characteristic set of functional groups that contributes greatly to its differing chemical properties and its function in living organisms. A functional group can participate in specific chemical reactions. Some of the important functional groups in biological molecules include: hydroxyl, methyl, carbonyl, carboxyl, amino, phosphate, and sulfhydryl groups.
These groups play an important role in the formation of molecules like DNA, proteins, carbohydrates, and lipids. Functional groups are usually classified as hydrophobic or hydrophilic depending on their charge or polarity. An example of a hydrophobic group is the non-polar methane molecule. Among the hydrophilic functional groups is the carboxyl group found in amino acids, some amino acid side chains, and the fatty acid heads that form triglycerides and phospholipids.
Other functional groups, such as the carbonyl group, have a partially negatively charged oxygen atom that may form hydrogen bonds with water molecules, again making the molecule more hydrophilic. Hydrogen bonds between functional groups within the same molecule or between different molecules are important to the function of many macromolecules and help them to fold properly and maintain the appropriate shape needed to function correctly.
Hydrogen bonds are also involved in various recognition processes, such as DNA complementary base pairing and the binding of an enzyme to its substrate. Privacy Policy. Skip to main content. The Chemical Foundation of Life.
Search for:. The Chemical Basis for Life Carbon is the most important element to living things because it can form many different kinds of bonds and form essential compounds. Learning Objectives Explain the properties of carbon that allow it to serve as a building block for biomolecules. Key Takeaways Key Points All living things contain carbon in some form.
Carbon is the primary component of macromolecules, including proteins, lipids, nucleic acids, and carbohydrates. The carbon cycle shows how carbon moves through the living and non-living parts of the environment. Key Terms octet rule : A rule stating that atoms lose, gain, or share electrons in order to have a full valence shell of 8 electrons has some exceptions. Hydrocarbons Hydrocarbons are important molecules that can form chains and rings due to the bonding patterns of carbon atoms.
Learning Objectives Discuss the role of hydrocarbons in biomacromolecules. Key Takeaways Key Points Hydrocarbons are molecules that contain only carbon and hydrogen.
The bonding of hydrocarbons allows them to form rings or chains. Key Terms covalent bond : A type of chemical bond where two atoms are connected to each other by the sharing of two or more electrons. Organic Isomers Isomers are molecules with the same chemical formula but have different structures, which creates different properties in the molecules.
Learning Objectives Give examples of isomers. Key Takeaways Key Points Isomers are molecules with the same chemical formula but have different structures. Isomers differ in how their bonds are positioned to surrounding atoms. Triglycerides, which show both cis and trans configurations, can occur as either saturated or unsaturated, depending upon how many hydrogen atoms they have attached to them. Organic Enantiomers Enantiomers share the same chemical structure and bonds but differ in the placement of atoms such that they are mirror images of each other.
Learning Objectives Give examples of enantiomers. Key Takeaways Key Points Enantiomers are stereoisomers, a type of isomer where the order of the atoms in the two molecules is the same but their arrangement in space is different.
Many molecules in the bodies of living beings are enantiomers; there is sometimes a large difference in the effects of two enantiomers on organisms. Key Terms enantiomer : One of a pair of stereoisomers that is the mirror image of the other, but may not be superimposed on this other stereoisomer.
Organic Molecules and Functional Groups Functional groups are groups of molecules attached to organic molecules and give them specific identities or functions. Learning Objectives Describe the importance of functional groups to organic molecules. Key Takeaways Key Points Functional groups are collections of atoms that attach the carbon skeleton of an organic molecule and confer specific properties.
Each type of organic molecule has its own specific type of functional group. Functional groups in biological molecules play an important role in the formation of molecules like DNA, proteins, carbohydrates, and lipids. Functional groups include: hydroxyl, methyl, carbonyl, carboxyl, amino, phosphate, and sulfhydryl. Key Terms hydrophobic : lacking an affinity for water; unable to absorb, or be wetted by water hydrophilic : having an affinity for water; able to absorb, or be wetted by water.
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