All living things depend on chemical interactions to maintain life.

Metabolism is the sum of all chemical interactions in the body. When metabolic processes malfunction or stop, the organism loses homeostasis and becomes ill or diseased.

Chemistry is the study of the interactions between atoms and their combination into molecules. 

Atoms interact by sharing electrons.  The manner in which atoms share electrons gives the chemical reaction a unique characteristic - or

Said another way - the manner in which atoms share electrons gives the chemical reaction a unique function.  or 

Said another way - the chemical behavior (function) of an atom is determined by the number and arrangement of electrons.

.  At the biological level: Chemistry is the study of how atoms share electrons.
When atoms share electrons, they either BOND together and form molecules or one atom loses an electron and the other gains an electron.

What gives a chemical reaction a unique function?
How are the two ways that chemistry has been defined similar?

Basic chemical characteristics are responsible for the structure and functions of life such as the Colloid mixture (protoplasm) inside cells and in the make up organelles.

Remember Homeostasis? 
Define it.
Living organisms USE the unique function of each chemical reaction to control the flow of energy through the organism - and maintain life.  The organism that best utilizes the unique function of each chemical reaction is able to best maintain homeostasis.

The protons and neutrons make up the nucleus of the Atom, while electrons 'orbit' the nucleus.  The energy for life is found in the electrons.  Atoms bond to other atoms through the 'sharing of electrons'.

Where is energy found?

An understanding of the particles that make up molecules is essential.
These particles are Atoms.

Look at a periodic table of the elements.

The elements are made up of atoms.

Matter - anything that has mass and occupies space.

An element is the simplest form of a substance. An element cannot be broken down into any other substances under NORMAL conditions - i.e. the conditions of life here on earth.  If you throw gold into the sun - the 6000 Kelvin temperature will change gold into something else.  Ditto if you through almost any other element into the sun -or onto Jupiter (immense gravity of Jupiter potentially could cause some change).

Each Element has UNIQUE chemical properties - conferred by the number of protons and neutrons that make up its nucleus and the number of electrons in the 'energy shells' around the nucleus.

An atom is the smallest particle of an element.
      Remember - the levels of organization that we use start with the atom.

  An atom is made up of subatomic particles called:
       protons - positive electrical charge   - found in the nucleus

       neutrons - neutral electrical charge   - found in the nucleus

       electrons - negative electrical charge  - in energy shells around the nucleus
               the first shell has 2 electrons

               The subsequent shells need 8 to be considered 'full'.

Look at a periodic table of the elements.

The first element, Hydrogen, is #1 because it consists of only 1 proton and 1 electron. If you remove the electron, a proton remains which has a + charge – making it a hydrogen ion. Therefore, a hydrogen ion and a proton are the same thing. Be sure you know this, because when talking about acidity, we will come back to this concept.

Chemistry is the study of the reactions between atoms and/or molecules. Living organisms break molecules apart and use the pieces and the energy contained in the bonds between the atoms to construct new molecules for use in metabolism, homeostasis, and growth and development.

What electrical charge does a proton have?

What electrical charge does an electron have?

What electrical charge does a neutron have?

Some elements readily gain or loose an electron. This produces an atom or molecule that has a charge.
A Na atom that has lost an electron has a positive electrical charge and is written as.....    Na+.
A Cl atom that has gained an electron has a negative electrical charge and is written as.....    Cl-.

An ion or electrolyte is an atom or molecule with an electrical charge.

  Cation - an ion with a POSITIVE electrical charge.  H+, Na+, K,+, Ca++

  Anion - an ion with a NEGATIVE electrical charge. Cl-, (OH)-, HCO3-,
Name some electrolytes

    (ions – hint – look on a Periodic Table of the Elements – "Google" it or look it up in a chemistry book).
  Look at the table, in your text, of common ions in the body.
Where have you heard this term before?

   Electrolytes are called 'electro' because these IONS in solution can pass and electrical current/charge through that solution.

The chemical symbols are easily found on a Periodic Table of the Elements. Your text has tables that list the common elements in the human body.

     Know the symbols for the major elements found in the body.

     Know the symbols for the major ions found in the body.

     What is the function of Ca++ in the body?

     What is the function of Na+?

     What is the function of K+?

What are 'minerals' in the diet?

  Look on a nutrition label for a multivitamin and mineral supplement.

   List some minerals.

     Now, look at a periodic table of the elements.
        See anything familiar?

Ion = electrolyte = solute = mineral

Atoms interact with one another by SHARING ELECTRONS. They form BONDS when they share the electrons. Although there are several types of bonds, we will concentrate only on Covalent, Ionic and Hydrogen bonds. When atoms form bonds with each other - they form a MOLECULE.

Nonpolar molecules are molecules that do NOT have an electrical charge – the whole molecule is electrically neutral. For this reason water cannot adhere to these molecules. Another term that describes nonpolar molecules is Hydrophobic (water fearing or hating) since they do not dissolve in water. Examples of nonpolar molecules include Fats, oils, steroids, etc – Lipid molecules. Nonpolar molecules easily dissolve in nonpolar solvents – such as alcohol, gasoline, turpentine, diesel oil, cooking oil, etc. You can mix lard easily with butter but lard does NOT mix easily with water.

What happens when you mix olive oil and vinegar?
   WHY?
     Describe this in terms of polarity.

Define metabolism
What are the two types of metabolism?

Catabolism is a decomposition reaction - breaking a single molecule into two or more parts..
        Each catabolic reaction in the body is a HYDROLYSIS reaction - that is - a reaction in which
         WATER (H2O) is split into H+ and (OH)-. 

    H+ is a proton, a (+) ion
    (OH)- is a hydroxide ion, a (-) ion.

 

The molecule to be decomposed, is split by an enzyme, and the H+ is bonded to one part, while the (OH)- is bonded to the other part - forming two new molecules from the original one molecule.

Anabolism is a synthesis reaction - BUILDING a new molecule out of building blocks - or two other molecules.
    This is accomplished through a mechanism called DEHYDRATION SYNTHESIS - synthesis by
      removing a water molecule.

    Each anabolic reaction begins with the removal of a H+ from one molecule and an (OH)- from another molecule.  The H+ and (OH)- combine to form ....... yep..... water - H2O

Meanwhile the two original molecules are joined to form a single new molecule.

In living systems, both catabolism and anabolism require WATER!.

Now, let's discuss WATER.

 The Characteristics of Water are very important concepts - therefore, much of this course will ask questions about the characteristics of water and how each supports the functions of life.

Water makes up 66% (2/3) of the mass of the human body.  Water makes up 90% of the mass of the cell. Water makes up 95-98% of the fluids in the body.

Why does water only make up 66% of the total mass of the body?

Describe the important characteristics of water.

1. Dipolar molecule – the water molecule is made of 2 hydrogen atoms covalently bonded to an oxygen
       atom. Because hydrogen only has 1 proton, it does not hold tightly to the electron. The oxygen has 6
       protons and badly WANTS two more electrons - therefore oxygen pulls the electrons from the
       hydrogens. Since the electrons spend most of their time around the oxygen atom and very little time
       around the hydrogens, the water molecule has an electrically ‘positive’ side (the hydrogens) and an
       electrically ‘negative’ side (the oxygen) – the molecule is ‘charged’. This allows water to form
       hydrogen bonds with other polar molecules.

Draw and label a water molecule.

Show its polarity.

What is the molecular formula for water?

2. Hydrogen bonds – (H-bonds) since water is dipolar, with a positive and negative side, it is able to
    bond weakly to other polar molecules including itself. This weak attraction gives water a number of
    biologically important characteristics:

a. Adhesion and cohesion – because water can form H-bonds it can cohere (stick) to itself, and
    adhere (stick) to other polar particles. Adhesion allows water to ‘dissolve’ polar molecules. Cohesion
    allows water to stick to itself and form a liquid.

b. Liquid at Life Temperature – what does ‘room temperature mean’? LIFE temperature – water is a
    LIQUID at the temperature at which metabolism, i.e. life processes, takes place. Because water
    forms many, many H-bonds with itself (coheres so tightly) it is a liquid at room temperature. No other
    molecule of this size is a liquid at Life Temperature.

c. Viscosity – water has a specific, stable flowability at life temperatures. The body uses this flowability
     to transport nutrients in the blood. Diffusion and active transport and enzymatic reactions depend on
     this stable flowability of water molecules.

d. Near constant volume – water is a ‘shock absorber’ in connective tissues between bones, muscles,
     ligaments, etc. you can put pressure on the joint, and water in the connective tissue is ‘squeezed’ out.
     When the pressure is released, the water is reabsorbed into the connective tissue, waiting for the
     next ‘pressure’ event.

e. Universal solvent – because many, many polar molecules and ions easily dissolve in liquid water.
    This makes these molecular and atomic size pieces available for metabolism, in a liquid that allows
    the particles to move around but not too fast or too far. This facilitates chemical reactions by allowing
    the particles to move around and be manipulated, without allowing the particles to move to fast or get
    too far away.

f. High Specific Heat Capacity – anything in the body that deals with TEMPERATURE, relies on this
   characteristic. Mammals (human beings) are homeothermic. The ability to remain at a constant internal
   temperature depends on the water molecule. Water buffers temperature changes in the body. Water
   absorbs lots of excess heat energy in a hot body and releases lots of excess heat energy in a cold
   body.

g. Essential Reactant – water is REQUIRED for the metabolism of the body. It is used by enzymes to
    catabolize and anabolize organic molecules.

What is metabolism?
How is water involved in these chemical reactions?
    What is hydrolysis?
    What is dehydration synthesis?

Compare and Contrast the states of matter: Solid, Liquid, and Gas.

A solid is ‘solid’ because the atoms/molecules cannot move around – and therefore the
     atoms are NOT readily available for chemical reactions.

 

A liquid is a system in which the atoms and molecules that make up that system are
    attached to each other, BUT, can move around each other.  

      Because the atoms and molecules in a liquid can move around each other,
      those atoms and molecules can be easily ‘reacted’ by chemicals.

 

      Chemical reactions (metabolism) involve MOVING the atoms around,
      rearranging them, changing the organization - Catabolizing and Anabolizing -
      of molecules.

A gas is a ‘gas’ because the atoms/molecules are NOT attached to one another – and
     therefore the atoms/molecules are too active (and too far apart)  for the controlled
     metabolism of living things.

Why does "life’ need a ‘liquid’?
     Hint: What is the 'characteristic' or 'function' of liquid that supports chemical reactions?

Define solid, liquid, and gas.

 

Life requires that atoms and molecules be able to MOVE around without moving too fast, or too far. A liquid allows atoms and molecules to move around, but keeps them in contact with each other, therefore chemical reactions have the opportunity to occur.

 

 

Water is either inside the cell or it is outside the cell.
                               Remember: the cell is the basic unit of life;
                               And the cell controls its internal environment.

Inside the cell is termed ‘intracellular’. (Note: this is inTRAcellular – NOT intercellular.)
   Intracellular fluid - ICF
   aka - cytoplasm

Outside the cell has 3 terms: EXTRAcellular, intercellular, and interstitial.
   Extracellular fluid - ECF

      Examples of extracellular fluids include: blood and lymph, interstitial fluid, pleural fluid,
      lymph, the aqueous humor (inside the eye), synovial fluid, fluid in the matrix of connective
      tissues, etc. – ANY fluid that is external to the cell.

Name the two places water is found in the body.
Give some examples of ICF and ECF.

Glucose is a molecule of sugar that is STORED energy.  To use the energy, we must transfer the energy to a molecule in which the energy is readily available.

Cellular respiration is the CATABOLISM of glucose in which the stored energy is transferred to a molecule in which the energy is readily useable.
 

Cellular respiration is the breakdown of glucose (sugar) molecules to release energy contained in the chemical bonds between the atoms that make up the glucose molecule.

As the glucose molecule is broken apart, electrons (full of energy) are stripped from the molecule and passed from one electron carrier molecule to the next and ultimately to an oxygen atom –
       remember oxygen WANTS 2 electrons very badly.

Carbon dioxide is the waste product of the glucose molecule and contains no useable energy for living organisms.

The energy is transferred to ATP molecules – the energy molecule of the cell. ALL cellular processes use ATP as an energy source.

What is the energy molecule of the body?

What process produces this molecule?

The term pH describes the concentration of H+ (hydrogen ions) in a solution. The more H+, the more acidic the solution. The fewer H+ ions, the more basic the solution.

Do NOT use higher acidity to describe an acid – the term ‘higher acidity’ is ambiguous.

Use ‘more acidic’ or ‘less acidic’ or ‘more basic’ or ‘less basic’.

Look at the pH scale in your text.
 

Normally, pH 7 is considered NEUTRAL and has the same number of H+ as (OH)- loose in
    the solution.
         There are equal numbers of protons and hydroxide ions.

A pH less than 7 (i.e. 6, 5, 4... 0) is ACIDIC - there are more H+ than (OH)- loose in solution.
         Said another way - a solution with excess H+ is acidic.

A pH greater than 7 (i.e. 8, 9, 10... 14) is BASIC (Alkaline). - there are more (OH)- than H+
     loose in solution.

          Said another way - a solution with excess (OH)- or too few H+.

What does the term pH mean?

List some common solutions with pH 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, and 14

The normal pH of the human body is 7.4 (see blood on the pH scale)
The RANGE of pH is 7.35 to 7.45.

A person with pH less than 7.35 is considered to be acidic. (note that the NORM is 7.35 to 7.45)

A person with pH greater than 7.45 is considered to be basic.

What is the normal pH of the body/blood?

What is the range of pH in body fluids?
       of stomach acid?
       of urine?
       of soda water?
       of vinegar?
       of ammonia
       of oven cleaner?

 

What is a proton?
How is it related to a H+? (see above about atoms)

Why is the pH range for blood (and body fluids) so narrow?

   Excess H+ cause damage to proteins.
   Too few H+ (excess (OH)- ) also cause damage to proteins.

An ACID is a proton donor- what is a proton? Remember –it’s a hydrogen ion!
An acid is a molecule that has hydrogen atoms to which it is very loosely bound – it will ‘donate’ these hydrogens, as ions, to the solution.

pH 1 is a condition in which there are LOTS of H+  (i.e. Protons) loose in the system.

   it is a STRONG acid.

A BASE is a proton acceptor. It is a molecule that WANTS a hydrogen ion. Why would an atom or molecule want a hydrogen ion?
Remember the hydrogen ion has a positive electrical charge. What type of molecule or atom would want a positive charge – one that has a negative electrical charge.

pH 14 is a condition in which there are 0 (zero) H+ loose in the system.... therefore, there are LOTS of (OH)- loose in the system.
  It is a STRONG base.

A BUFFER is a molecule that acts as either a proton donor or a proton acceptor. This means that whenever there are too many H+ in solution (acidic), the molecule ‘accepts’ (binds) H+ and removes them from the solution - fewer total H+ in solution makes the solution LESS acid – i.e. more basic.
Whenever there are too few H+ in solution (basic/alkaline solution), the molecule ‘donates’ (releases) H+ into solution – more H+ makes the solution less basic – i.e. more acid. This ability to accept or donate H+ ions to the solution, helps maintain a relatively constant H+ concentration – i.e. it buffers the pH.

Sodium Bicarbonate (NaHCO3) is a very important buffer in the human body

Acidosis vs. alkalosis: Acidosis is an acid pH, Alkalosis is a basic pH.
   Respiratory acidosis or alkalosis results from a malfunction of the respiratory system.
   Metabolic acidosis or alkalosis results from a malfunction of metabolic processes
  (urinary system).

Acidotic - a person whose fluids are too acidic due to either respiratory or
        metabolic acidosis
Alkalotic - a person whose fluids are to basic due to either respiratory or
        metabolic alkalosis.

 

Define acid, base, buffer, acidosis, alkalosis.

What is sodium bicarbonate?

Describe the functions and types of sugars, fats, and proteins

There are 4 types of Organic molecules in living things:

carbohydrates - (sugars, starch, glycogen, etc.)

lipids - (fats, steroids, etc.)

proteins - (enzymes, etc.)

nucleic acids - (DNA, RNA, etc.)

 

Three of these are in general use throughout living things while nucleic acids have specific uses. These are called ‘organic’ molecules because they consist of a chain of carbon atoms bonded together.

 

Why are they called organic molecules?
List the four types of organic molecules.

Carbohydrates are POLAR molecules such as the sugars - glucose and fructose.
  The primary function is storage of energy.
     Glucose molecule - the basic, repeating unit or building block of carbohydrates
       In animals, glucose is stored as glycogen in the liver.
       In plants, glucose is stored as starch.

Lipids are NONPOLAR molecules such as the fats, oils, steroids and phospholipids.
   Triglycerides and glycerol molecule - the basic, repeating unit or building block of lipids.
           Fats are solid at room temperature while
           Oils are liquid at room temperature.

The primary function of fats and oils is to store energy in animals – about 99% of the excess energy in animals is stored as fat molecules.

Proteins are POLAR molecules. Amino Acid (AA) - the basic, repeating unit or building block of proteins - each protein is a chain of AAs which are in a specific sequence that gives the protein a specific shape - and therefore a specific function.

Proteins are the workhorse of the cell and living organism. All the structures are held together by proteins, all the chemical reactions (what is the term for all the ‘chemical reactions in the body’?) are mediated by proteins. Each proteins has a specific function that depends on the SHAPE of the protein. There are 4 basic shapes:

Primary – a string or rope-like linear structure. Microfilaments and micro tubules

Secondary – folded, twisted primary proteins – with a 3-D shape either spiral or
     sheet like. The sheet looks like a piece of paper.

Tertiary – a ‘glob’ of primary and secondary shapes all wadded up into a ball.
     The globulins of the antibodies in the immune system are examples.

Quaternary – a blob of primary, secondary and tertiary shaped proteins
     attached to one another. The hemoglobin molecule is an example.

Support and Structural – internal and external support of cells

Movement – contractile proteins

Transport – insoluble lipids, respiratory gases, minerals are carried in the blood
     attached to transport proteins.

Buffering pH – proteins are polar molecules and bind or release H+ as needed to
     the surrounding solution. i.e. Blood (plasma) proteins.

Metabolic regulation – Enzymes promote chemical reactions.

Coordination, communication and control – Hormones regulate growth,
     maintenance, and development of the body

Defense – tough waterproof proteins in the skin, hair and nails. Antibodies of the
    immune system. Clotting proteins for blood clotting.

Denature – the structure of the protein changes so much that it is NONfunctional – i.e. the protein can no longer do what it is supposed to do. Some conditions that denature proteins are Temperature, pH, hydration, electrolyte concentration.

List the four shapes of proteins.

Why is ‘shape’ important to proteins?

How is this important to ‘life’?

Enzymes are protein molecules that promote (catalyze) or control chemical reactions (i.e. metabolism!!).
  What is metabolism?
Each enzyme has a unique shape that exactly fits only one (1) substrate. A substrate is the ‘food’ for a chemical reaction. When that substrate is present, it binds to the enzyme and the substrate is chemically changed. Because the enzyme has a specific shape, the shape of the substrate 'fits' the active site of the enzyme and sticks to the enzyme long enough for the reaction to occur.
Enzymes function in a very controlled fashion and therefore break down or build new molecules in a very controlled manner. The enzymes cause the reaction, but are not changed by that reaction. Once the reaction is complete, the enzyme is ready to catalyze the same reaction with another substrate molecule.

What is ‘metabolism’?

What is the function of enzymes?

How are enzymes important to life?

What ‘gives’ enzymes their specific function?

How is the enzyme shape related to the 'active site' and to the 'substrate'?

How are H-bonds related to enzyme shape?

List some things that ‘denature’ enzymes.

How do these conditions 'denature' the enzyme?

Define homeostasis.

What are the building blocks for each of the organic molecules?

The repeating unit is the NUCLEOTIDE

there are five nucleotides:

RNA - ribonucleic acid - nucleotides that make up RNA are  A U C and G

DNA - Deoxyribonucleic acid  -  nucleotides that make up DNA are A T C and G.

   NOTE: RNA contains URACIL, where DNA contains Thymine

ATP - adenosine tri phosphate

What is the difference between RNA and DNA?

DNA is deoxyribonucleic acid and is the molecule that makes up the chromosomes and
     stores the genetic information for each species.

RNA is ribonucleic acid and is the molecule that carries the genetic information from the
     DNA to the cytoplasm where it is used for metabolism, growth and development and
     homeostasis.

ATP is adenosine tri-phosphate. It is the ENERGY molecule of all the metabolic reactions
     in the human body. Although much energy can be found in the body – it must be converted
      to ATP so that it can be used.

(These terms should be treated as new vocabulary.)

• Proton

• Electron

• Nucleus

Ions

Ca++
H+
(OH)-
K+
Cl-
Na+

• Carbon Dioxide - CO₂

• Oxygen - O₂

• Water - H₂O

• Inorganic Acids  - hydrogen chloride - HCl

• Inorganic Bases - sodium hydroxide - NaOH

• Salts  - sodium chloric,- NaCl, magnesium chloride - MgCl, calcium chloride - CaCl_2,

• sodium bicarbonate  NaHCO₃

• Carbohydrates

  • Monosaccharides

  • Disaccharides

  • Polysaccharides

    • Glucose Formula C₆H₁₂O₆

• Lipids

  • Fatty Acids

  • Fats

  • Steroids

• Proteins

• Nucleic Acids

• High Energy Compounds