Basic Chemistry H Anatomy and Physiology

Atom

Smallest particle of an element that has the properties of that element

Electron (e-)

Extremely small particle; carries a negative electrical charge and is in constant motion around the nucleus of an atom

Proton (p+)

Relatively large particle; carries a positive electrical charge and is found within the nucleus of an atom

Neutron (n0)

Relatively large particle; uncharged and thus electrically neutral; found within the nucleus of an atom

Molecule

Particle formed by the chemical union of two or more atoms

Ion

Atom or molecule that is electrically charged because it has gained or lost one or more electrons

Lipids

organic substances that are insoluble in water but soluble in certain organic solvents, such as ether and chloroform. Lipids include a variety of compounds— fats, phospholipids, and steroids—that have

Fats are used primarily to

store energy for cellular activities. Fat molecules can supply more energy, gram for gram, than carbohydrate molecules.

fat molecules are composed of

carbon, hydrogen, and oxygen atoms (Like carbohydrates).

The building blocks of fat molecules are

fatty acids and glycerol (glis′er-ol). Each glycerol molecule bonds with three fatty acid molecules to produce a single fat, or triglyceride, molecule

A phospholipid molecule is

similar to a fat molecule in that it consists of a glycerol portion and fatty acid chains. A phospholipid, however, has only two fatty acid chains; in place of the third is a portion that includes a phosphate group.

The phosphate portion is soluble in water

(hydrophilic) and forms the "head" of the molecule.

The fatty acid portion is insoluble in water

(hydrophobic) and forms a "tail"

Phospholipids are important in cellular structures.

hydrophobic

insoluble in water

hydrophilic

soluble in water

Steroid molecules are complex structures that include four connected rings of ____________________

carbon atoms.

the more important steroids are

cholesterol, which is in all body cells and is used to synthesize other steroids: sex hormones, such as estrogen, progesterone, and testosterone; and several hormones from the adrenal glands.

Carbohydrates

provide much of the energy that cells require. They supply materials to build certain cell structures and often are stored as reserve energy supplies.

sugars

The carbon atoms of carbohydrate molecules join in chains whose lengths vary with the type of carbohydrate. For example, carbohydrates with shorter chains are called ____________.

Hexoses

Sugars with 6 carbon atoms (simple sugars, or monosaccharides)

Simple sugars include

glucose, fructose, and galactose, as well as the 5-carbon sugars ribose and deoxyribose.

monosaccharides

simple sugars

complex carbohydrates

a number of simple sugar molecules link to form molecules of varying sizes. Some complex carbohydrates, such as sucrose (table sugar) and lactose (milk sugar), are double sugars, or disaccharides, whose molecules each consist of two simple sugar building blocks. Other complex carbohydrates are made up of many simple sugar units joined to form polysaccharides, such as plant starch.

complex carbohydrates

sucrose (table sugar) and lactose (milk sugar), are double sugars, or disaccharides, whose molecules each consist of two simple sugar building blocks.

plant starch

complex carbohydrates made up of many simple sugar units joined to form polysaccharides

respiratory

Molecules of oxygen (O2) enter the body through the _____________ organs and are transported throughout the body by the blood.

oxygen

Cellular organelles use _________ to release energy from the sugar glucose and other nutrients. The released energy drives the cell's metabolic activities.

red blood cells

The ______________ bind and carry most of the oxygen.

Carbon dioxide (CO2)

a simple, carbon-containing compound of the inorganic group produced as a waste product when certain metabolic processes release energy, and it is exhaled from the lungs.

Lipids

organic substances that are insoluble in water but soluble in certain organic solvents, such as ether and chloroform.

Lipids include a variety of compounds

fats, phospholipids, and steroids

fats

The most common lipids.

Triglycerides

Three fatty acid molecules bound to a glycerol molecule

Phospholipids

Two fatty acid molecules and a phosphate group bound to a glycerol molecule

Steroids

Four connected rings of carbon atoms

Building Blocks of Carbohydrates

Simple sugars

Building Blocks of Lipids

Glycerol, fatty acids, phosphate groups

Building Blocks of Proteins

Amino acids

Building Blocks of Nucleic Acid

Nucleotides

ionic bond (electrovalent bond)

Formed by transfer of electrons; strong electrostatic force that binds positively & negatively charged ions together

covalent bond

a chemical bond that involves sharing a pair of electrons between atoms in a molecule

polar

having a pair of equal and opposite charges

molecule

When two or more atoms bond, they form a new kind of particle called a

molecular formula

a chemical formula based on analysis and molecular weight

decomposition

If the bonds within a reactant molecule break so that simpler molecules, atoms, or ions form, the reaction is called ______________

exchange reaction

parts of two different types of molecules trade positions as bonds are broken and new bonds are formed.

Acids

electrolytes that release hydrogen ions (H+) in water.

bases

Electrolytes that release ions that bond with hydrogen ions.

catalysts

speed many chemical reactions in the body so that they proceed fast enough to sustain the activities of life.

Buffers

chemicals that resist pH change. They combine with hydrogen ions when these ions are in excess, or they donate hydrogen ions when these ions are depleted.

organic chemicals

include both carbon and hydrogen atoms. The rest are inorganic.

two types of Nucleic acids

RNA (ribonucleic acid) composed of molecules whose nucleotides have ribose. RNA usually is a single polynucleotide chain, but it can fold into various shapes that enable it to control when certain genes are accessed. The second type—DNA (deoxyribonucleic acid) has deoxyribose and forms a double polynucleotide chain. The two chains are held together by hydrogen bonds

DNA

(deoxyribonucleic acid) has deoxyribose and forms a double polynucleotide chain. The two chains are held together by hydrogen bonds

RNA

(ribonucleic acid) composed of molecules whose nucleotides have ribose. usually is a single polynucleotide chain, but it can fold into various shapes that enable it to control when certain genes are accessed.