What Is Carbon Used For In The Body

The Chemical Ground for Life

Carbon is the virtually important chemical element to living things because it tin form many different kinds of bonds and class essential compounds.

Learning Objectives

Explicate the properties of carbon that allow it to serve as a edifice block for biomolecules

Key Takeaways

Key Points

All living things incorporate carbon in some grade.
Carbon is the primary component of macromolecules, including proteins, lipids, nucleic acids, and carbohydrates.
Carbon'south molecular structure allows it to bond in many different ways and with many different elements.
The carbon cycle shows how carbon moves through the living and non-living parts of the environment.

Central Terms

octet rule: A dominion stating that atoms lose, gain, or share electrons in order to have a total valence shell of eight electrons (has some exceptions).
carbon cycle: the physical cycle of carbon through the earth'due south biosphere, geosphere, hydrosphere, and atmosphere; includes such processes as photosynthesis, decomposition, respiration and carbonification
macromolecule: a very big molecule, especially used in reference to large biological polymers (e.g., nucleic acids and proteins)

Carbon is the fourth most abundant element in the universe and is the building cake of life on globe. On earth, carbon circulates through the land, ocean, and atmosphere, creating what is known as the Carbon Cycle. This global carbon bike tin be divided further into ii separate cycles: the geological carbon cycles takes identify over millions of years, whereas the biological or physical carbon cycle takes place from days to thousands of years. In a nonliving environment, carbon can exist as carbon dioxide (CO₂), carbonate rocks, coal, petroleum, natural gas, and expressionless organic thing. Plants and algae convert carbon dioxide to organic matter through the process of photosynthesis, the energy of low-cal.

Carbon is present in all life: All living things contain carbon in some form, and carbon is the chief component of macromolecules, including proteins, lipids, nucleic acids, and carbohydrates. Carbon exists in many forms in this leaf, including in the cellulose to course the leaf's structure and in chlorophyll, the pigment which makes the foliage light-green.

Carbon is Of import to Life

In its metabolism of food and respiration, an brute consumes glucose (C_sixH₁₂O₆), which combines with oxygen (O₂) to produce carbon dioxide (CO_ii), water (H_twoO), and energy, which is given off as rut. The creature has no need for the carbon dioxide and releases it into the atmosphere. A plant, on the other hand, uses the opposite reaction of an beast through photosynthesis. It intakes carbon dioxide, water, and free energy from sunlight to make its own glucose and oxygen gas. The glucose is used for chemical energy, which the plant metabolizes in a like mode to an animal. The plant then emits the remaining oxygen into the environment.

Cells are made of many complex molecules called macromolecules, which include proteins, nucleic acids (RNA and Dna), carbohydrates, and lipids. The macromolecules are a subset of organic molecules (whatever carbon-containing liquid, solid, or gas) that are especially important for life. The fundamental component for all of these macromolecules is carbon. The carbon cantlet has unique properties that allow it to class covalent bonds to as many every bit four different atoms, making this versatile element ideal to serve as the basic structural component, or "backbone," of the macromolecules.

Construction of Carbon

Individual carbon atoms accept an incomplete outermost electron shell. With an atomic number of 6 (six electrons and six protons), the showtime ii electrons fill the inner shell, leaving four in the second shell. Therefore, carbon atoms can form 4 covalent bonds with other atoms to satisfy the octet rule. The methane molecule provides an example: information technology has the chemical formula CH₄. Each of its 4 hydrogen atoms forms a single covalent bond with the carbon cantlet by sharing a pair of electrons. This results in a filled outermost shell.

Structure of Methyl hydride: Methane has a tetrahedral geometry, with each of the four hydrogen atoms spaced 109.5° autonomously.

Hydrocarbons

Hydrocarbons are important molecules that can form chains and rings due to the bonding patterns of carbon atoms.

Learning Objectives

Discuss the part of hydrocarbons in biomacromolecules

Key Takeaways

Fundamental Points

Hydrocarbons are molecules that comprise simply carbon and hydrogen.
Due to carbon'south unique bonding patterns, hydrocarbons can have single, double, or triple bonds between the carbon atoms.
The names of hydrocarbons with unmarried bonds end in "-1," those with double bonds finish in "-ene," and those with triple bonds finish in "-yne".
The bonding of hydrocarbons allows them to form rings or chains.

Key Terms

covalent bond: A blazon of chemical bail where two atoms are connected to each other by the sharing of ii or more than electrons.
aliphatic: Of a class of organic compounds in which the carbon atoms are arranged in an open up chain.
aromatic: Having a closed ring of alternating unmarried and double bonds with delocalized electrons.

Hydrocarbons

Hydrocarbons are organic molecules consisting entirely of carbon and hydrogen, such every bit methane (CH₄). Hydrocarbons are often used as fuels: the propane in a gas grill or the butane in a lighter. The many covalent bonds between the atoms in hydrocarbons store a great amount of energy, which is released when these molecules are burned (oxidized). Methyl hydride, an excellent fuel, is the simplest hydrocarbon molecule, with a central carbon atom bonded to four different hydrogen atoms. The geometry of the marsh gas molecule, where the atoms reside in three dimensions, is adamant past the shape of its electron orbitals. The carbon and the four hydrogen atoms form a shape known equally a tetrahedron, with 4 triangular faces; for this reason, methane is described equally having tetrahedral geometry.

Methane: Methane has a tetrahedral geometry, with each of the 4 hydrogen atoms spaced 109.5° apart.

As the backbone of the large molecules of living things, hydrocarbons may exist as linear carbon bondage, carbon rings, or combinations of both. Furthermore, individual carbon-to-carbon bonds may be single, double, or triple covalent bonds; each type of bail affects the geometry of the molecule in a specific way. This three-dimensional shape or conformation of the big molecules of life (macromolecules) is critical to how they part.

Hydrocarbon Bondage

Hydrocarbon bondage are formed by successive bonds between carbon atoms and may be branched or unbranched. The overall geometry of the molecule is altered by the different geometries of unmarried, double, and triple covalent bonds. The hydrocarbons ethane, ethene, and ethyne serve as examples of how different carbon-to-carbon bonds impact the geometry of the molecule. The names of all three molecules showtime with the prefix "eth-," which is the prefix for 2 carbon hydrocarbons. The suffixes "-ane," "-ene," and "-yne" refer to the presence of single, double, or triple carbon-carbon bonds, respectively. Thus, propane, propene, and propyne follow the same pattern with iii carbon molecules, butane, butene, and butyne for four carbon molecules, and so on. Double and triple bonds alter the geometry of the molecule: single bonds permit rotation along the axis of the bond, whereas double bonds pb to a planar configuration and triple bonds to a linear 1. These geometries have a significant impact on the shape a item molecule can assume.

Hydrocarbon Bondage: When carbon forms single bonds with other atoms, the shape is tetrahedral. When ii carbon atoms class a double bail, the shape is planar, or flat. Single bonds, like those found in ethane, are able to rotate. Double bonds, like those found in ethene cannot rotate, so the atoms on either side are locked in place.

Hydrocarbon Rings

The hydrocarbons discussed so far accept been aliphatic hydrocarbons, which consist of linear chains of carbon atoms. Another type of hydrocarbon, aromatic hydrocarbons, consists of closed rings of carbon atoms. Ring structures are constitute in hydrocarbons, sometimes with the presence of double bonds, which can exist seen by comparison the structure of cyclohexane to benzene. The benzene ring is nowadays in many biological molecules including some amino acids and most steroids, which includes cholesterol and the hormones estrogen and testosterone. The benzene ring is as well found in the herbicide 2,4-D. Benzene is a natural component of crude oil and has been classified every bit a carcinogen. Some hydrocarbons have both aliphatic and effluvious portions; beta-carotene is an example of such a hydrocarbon.

Hydrocarbon Rings: Carbon can form five-and vi membered rings. Single or double bonds may connect the carbons in the band, and nitrogen may be substituted for carbon.

Organic Isomers

Isomers are molecules with the aforementioned chemical formula only have different structures, which creates dissimilar properties in the molecules.

Learning Objectives

Give examples of isomers

Primal Takeaways

Key Points

Isomers are molecules with the same chemical formula simply accept unlike structures.
Isomers differ in how their bonds are positioned to surrounding atoms.
When the carbons are leap on the same side of the double bond, this is the cis configuration; if they are on contrary sides of the double bail, it is a trans configuration.
Triglycerides, which show both cis and trans configurations, tin can occur every bit either saturated or unsaturated, depending upon how many hydrogen atoms they have fastened to them.

Key Terms

fatty acid: Any of a class of aliphatic carboxylic acids, of general formula CnH2n+1COOH, that occur combined with glycerol as beast or vegetable oils and fats.
isomer: Any of two or more than compounds with the same molecular formula merely with dissimilar structure.

The three-dimensional placement of atoms and chemic bonds within organic molecules is central to understanding their chemistry. Molecules that share the same chemical formula but differ in the placement (construction) of their atoms and/or chemic bonds are known as isomers.

Structural Isomers

Structural isomers (such every bit butane and isobutane ) differ in the placement of their covalent bonds. Both molecules have four carbons and ten hydrogens (C₄H_ten), merely the dissimilar arrangement of the atoms within the molecules leads to differences in their chemic properties. For instance, due to their different chemical properties, butane is suited for use as a fuel for cigarette lighters and torches, whereas isobutane is suited for use as a refrigerant and a propellant in spray cans.

Geometric Isomers

Geometric isomers, on the other mitt, accept similar placements of their covalent bonds merely differ in how these bonds are made to the surrounding atoms, especially in carbon-to-carbon double bonds. In the simple molecule butene (C₄H_viii), the two methyl groups (CH_three) tin be on either side of the double covalent bond central to the molecule. When the carbons are leap on the same side of the double bond, this is the cis configuration; if they are on opposite sides of the double bond, it is a trans configuration. In the trans configuration, the carbons form a more or less linear construction, whereas the carbons in the cis configuration make a bend (modify in management) of the carbon courage.

Isomers: Molecules that have the same number and type of atoms bundled differently are called isomers. (a) Structural isomers have a unlike covalent arrangement of atoms. (b) Geometric isomers have a dissimilar system of atoms around a double bond. (c) Enantiomers are mirror images of each other.

Cis or Trans Configurations

Cis and Trans Fatty Acids: These infinite-filling models show a cis (oleic acid) and a trans (eliadic acid) fatty acid. Notice the bend in the molecule cause past the cis configuration.

In triglycerides (fats and oils), long carbon chains known as fatty acids may contain double bonds, which can be in either the cis or trans configuration. Fats with at least one double bail between carbon atoms are unsaturated fats. When some of these bonds are in the cis configuration, the resulting bend in the carbon backbone of the concatenation means that triglyceride molecules cannot pack tightly, then they remain liquid (oil) at room temperature. On the other manus, triglycerides with trans double bonds (popularly chosen 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 hazard of cardiovascular disease, and so many food manufacturers have reduced or eliminated their use in contempo years. In dissimilarity to unsaturated fats, triglycerides without double bonds between carbon atoms are called saturated fats, pregnant that they comprise all the hydrogen atoms available. Saturated fats are a solid at room temperature and unremarkably of animal origin.

Organic Enantiomers

Enantiomers share the same chemical construction and bonds but differ in the placement of atoms such that they are mirror images of each other.

Learning Objectives

Give examples of enantiomers

Cardinal Takeaways

Key Points

Enantiomers are stereoisomers, a type of isomer where the gild of the atoms in the ii molecules is the same merely their arrangement in space is dissimilar.
Many molecules in the bodies of living beings are enantiomers; there is sometimes a large difference in the furnishings of two enantiomers on organisms.
Enantiopure compounds refer to samples having, within the limits of detection, molecules of only one chirality.
Compounds that are enantiomers of each other have the same concrete properties except for the management in which they rotate polarized light and how they collaborate with unlike optical isomers of other compounds.

Key Terms

enantiomer: One of a pair of stereoisomers that is the mirror image of the other, simply may non be superimposed on this other stereoisomer.
chirality: The phenomenon in chemistry, physics, and mathematics in which objects are mirror images of each other, simply are not identical.
stereoisomer: one of a prepare of the isomers of a compound in which atoms are bundled differently about a chiral center; they exhibit optical activity

Enantiomers

Stereoisomers are a type of isomer where the order of the atoms in the 2 molecules is the aforementioned but their arrangement in space is dissimilar. The two main types of stereoisomerism are diastereomerism (including 'cis-trans isomerism') and optical isomerism (also known every bit 'enantiomerism' and 'chirality'). Optical isomers are stereoisomers formed when disproportionate centers are nowadays; for example, a carbon with four different groups bonded to information technology. Enantiomers are ii optical isomers (i.east. isomers that are reflections of each other). Every stereocenter in ane isomer has the opposite configuration in the other. They share the same chemical structure and chemical bonds, but differ in the three-dimensional placement of atoms so that they are mirror images, much as a person's left and right hands are. Compounds that are enantiomers of each other have the same physical backdrop except for the direction in which they rotate polarized lite and how they collaborate 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 leaner, only never in their proteins. Similarly, the D-form of glucose is the master production of photosynthesis and the Fifty-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 ordinarily accept ii not-superposable structures. These two structures are mirror images of each other and are, thus, commonly called enantiomorphs; hence, this structural belongings is now unremarkably referred to as enantiomerism. Enantiopure compounds refer to samples having, within the limits of detection, molecules of simply i 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 ii enantiomers on living beings. In drugs, for instance, often only ane of a drug's enantiomers is responsible for the desired physiologic furnishings, while the other enantiomer is less active, inactive, or sometimes even responsible for adverse furnishings. Owing to this discovery, drugs composed of only one enantiomer ("enantiopure") can exist developed to raise the pharmacological efficacy and sometimes do away with some side effects.

Organic Molecules and Functional Groups

Functional groups are groups of molecules fastened to organic molecules and give them specific identities or functions.

Learning Objectives

Describe the importance of functional groups to organic molecules

Primal Takeaways

Primal 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 grouping.
Functional groups in biological molecules play an important role in the germination of molecules like DNA, proteins, carbohydrates, and lipids.
Functional groups include: hydroxyl, methyl, carbonyl, carboxyl, amino, phosphate, and sulfhydryl.

Cardinal Terms

hydrophobic: lacking an affinity for water; unable to absorb, or be wetted by h2o
hydrophilic: having an affinity for water; able to blot, or be wetted past h2o

Location of Functional Groups

Functional groups are groups of atoms that occur inside organic molecules and confer specific chemical properties to those molecules. When functional groups are shown, the organic molecule is sometimes denoted every bit "R." Functional groups are found along the "carbon backbone" of macromolecules which is formed by chains and/or rings of carbon atoms with the occasional substitution of an element such equally nitrogen or oxygen. 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 ain feature ready of functional groups that contributes greatly to its differing chemical properties and its office in living organisms.

Properties of Functional Groups

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 germination of molecules like Dna, proteins, carbohydrates, and lipids.

Classifying Functional Groups

Functional groups are usually classified as hydrophobic or hydrophilic depending on their charge or polarity. An case of a hydrophobic group is the not-polar methane molecule. Among the hydrophilic functional groups is the carboxyl group institute in amino acids, some amino acrid side chains, and the fatty acid heads that class triglycerides and phospholipids. This carboxyl group ionizes to release hydrogen ions (H⁺) from the COOH grouping resulting in the negatively charged COO^–group; this contributes to the hydrophilic nature of whatsoever molecule information technology is found on. Other functional groups, such equally the carbonyl grouping, have a partially negatively charged oxygen atom that may form hydrogen bonds with water molecules, over again making the molecule more hydrophilic.

Examples of functional groups: The functional groups shown here are plant in many different biological molecules, where "R" is the organic molecule.

Hydrogen Bonds between Functional Groups

Hydrogen bonds between functional groups (within the aforementioned molecule or between different molecules) are of import to the function of many macromolecules and help them to fold properly and maintain the appropriate shape needed to part correctly. Hydrogen bonds are likewise involved in diverse recognition processes, such equally Deoxyribonucleic acid complementary base pairing and the binding of an enzyme to its substrate.

Hydrogen bonds in DNA: Hydrogen bonds connect two strands of DNA together to create the double-helix structure.