ANAPHY: THE CHEMICAL LEVEL OF ORGANIZATION

Level of Organization

1. Chemical Level
2. Cellular Level
3. Tissue Level
4. Organ Level
5. System Level
6. Organismal Level

Atoms

The symbols of an element indicates 1 atom of that element. A number preceding the symbol of an element indicates more than 1 atom of that element.

Molecules

A numerical subscript following the symbol of an element indicates the number of atoms of that element in a molecule.

Ions

A superscript plus sign or minus sign following the symbol of an element indicates an ion.

+1

The original atom has given up 1 electron

-1

The original atom has gained 1 electron.

Decomposition reactions or Catabolism

For example, a meal contains fats, sugars, and proteins that are too large and too complex to be absorbed and used by your body.

Synthesis reactions or Anabolism

Combination of molecules to form even larger products; always involves the formation of new chemical bonds.

Exchange reactions

Parts of the reacting molecules are shuffled around to produce new products.

Chemical Reactions

A chemical reaction occurs when new bonds are formed or old bonds are broken

Reactants

starting substances

Products

ending substances

Water

• Most abundant; plasma is 91% water; takes part in photosynthesis and respiration which produces energy

• Water also absorbs and releases high levels of heat before its temperature changes, thus helping control normal body temperature

Carbon Dioxide (CO2)

• Produced as a waste product of cellular respiration

• Convert the radiant energy into usable chemical energy such as glucose

• Source of the element carbon, found in all organic compounds of living systems

Molecular Oxygen (O2)

• Required by all organisms that breathe air

• Convert chemical energy (food) into another form of

energy (ATP)

• 21% content in the atmosphere

Mineral Salts or Electrolytes

• Essential for the survival and functioning of the body’s cells

• Calcium (Ca+)
• Phosphate (PO4)
• Chloride (Cl2)
• Sodium (Na+) and potassium (K+)

Calcium (Ca+)

Necessary for muscle contraction and nervous transmission as well as building strong bones

Phosphate (PO4)

Necessary to produce the high-energy molecule ATP

Chloride (Cl2)

Necessary for nervous transmission

Sodium (Na+) and potassium (K+)

Necessary for muscle cell contraction and nervous transmission

Ammonia (NH3)

• Comes from the decomposition of proteins via the digestive process and the conversion of amino acids in cellular respiration to ATP molecules.

• The important element is Nitrogen

• Through enzymes, the liver converts the toxic __________ to a harmless substance called urea

Carbohydrates (C6H12O6)

• Ribose and deoxyribose, which are parts of the RNA and DNA

• Note the repetition of the H-C-OH unit in the molecule

• Energy storage (sugars, starch, glycogen) and cell strengthening (cellulose and chitin)

Lipids

• Insoluble in water
• Fats, phospholipids, steroids, prostaglandin

Proteins

• Composed of carbon, hydrogen, oxygen, and nitrogen covalently bonded

‘• Part of cell membranous structures: plasma membrane, nuclear membrane, endoplasmic

• Reticulum, and mitochondria. In addition, actin and myosin found in muscle cell

• Enzymes

• Antibodies

• Source of energy converted to ATP

• Hydrogen bonds can be broken by high temperatures or increased acidity

Nucleic acids

• DNA and RNA
• CHONP

Adenosine triposphate

• Energy stored in the molecule is then used to run the cell and to perform activities such as repair, reproduction, assimilation, and transport of materials across cell membranes.

Buffers

Compounds that stabilize the pH of a solution by removing or replacing H+

Buffer systems

Usually involve a weak acid and its related salt, which functions as a weak base

Organic compounds

Made up of long chains of carbon atoms linked by covalent bonds forming additional covalent bonds with H+ or O2 atoms and, less commonly, with N2, P, S, Fe, or other elements

Macromolecule

Made up of monomer subunits bonded to other identical molecules to form a polymer; joined together through dehydration synthesis reactions; separated, or released, through hydrolysis reactions.

Carbohydrates

• An organic molecule that contains carbon, hydrogen, and oxygen in a ratio near 1:2:1

• Account for less than 1% of total body weight

• Most important as energy sources that are catabolized

Lipids

• Contain carbon, hydrogen, oxygen, and the carbon-to-hydrogen ratio is near 1:2; 12-18% of the total body weight of adult men, and 18-24% for adult women.

• Contain much less oxygen than do carbohydrates with same carbon atoms

• Most lipids are hydrophobic, or insoluble in water, but special transport mechanisms carry them into the bloodstream

Fatty acid

Saturated if it contains only single covalent bonds such as those found in whole milk, butter, eggs, beef, pork, and coconut and palm oils. Too much of these could cause cardiovascular disease; tend to be solids at room temperature.

Unsaturated fatty acids

Good for you and are found in sunflower, corn, and fish oils; tend to be liquids at room temperature.

Ecosanoids

Lipids derived from arachidonic acid, a fatty acid that must be absorbed in the diet because the body cannot synthesize it; leukotrienes and prostaglandins.

Triglycerides

Triacylglycerols or neutral fat; energy sources; insulation, protection

Steroids

Differ in the functional groups that are attached to this basic framework

Cholesterol

Contained in plasma membrane

Bile salts

Steroid derivatives are required for the normal processing of dietary fats

Proteins

Most abundant organic molecule in the human body; 20% of the total body weight

Amino acids

Simple organic compounds that combine to form proteins

Support

Structural proteins

Movement

Contractive proteins

Transport

Transport proteins

Metabolic regulation

Enzymes

Coordination and control

Protein hormones

Defense

Special clotting proteins

Shape of a protein

Determines its functional characteristics

Sequence of amino acids

Ultimately determines it shapes

Primary structure of a protein

Determined by its amino acid sequence.

Secondary structure

Determined by the hydrogen bonds between amino acids that cause the protein to coil into helices or pleated sheets. This shape is crucial to the functioning of proteins. Once H-bonds are destroyed proteins becomes nonfunctional.

Tertiary structure

Secondary folding caused by interactions within the peptide bonds and between sulfur atoms of different amino acids

Quaternary structure

Determined by the spatial relationships between individual units.

Enzyme function

• Most important of all the body’s proteins

• Catalyze the chemical reactions that sustain life

Substrates

Reactants in enzymatic reactions

Specificity

Catalyzes only one type of reaction