Why should we have a basic understanding of science and chemistry?

Know

Adenosine Triphosphate (ATP)

Allows the body cells to do work and function.

Chemistry

The science that deals with the elements, their compounds, the chemical reactions that occur between elements and compounds, and the molecular structure of all matter.

Atoms

The smallest particles of an element that maintains all the characteristics of that element and enter into chemical reactions through their electrons.

As basic as it gets.

Element

A substance whose atoms all contain the same number of protons and the same number of electrons. Atoms are electronically neutral.

John Dalton's (1808)

Atomic Theory

The atomic theory proposed that:

* All mater is made up of timy particles called atoms.
* All atoms of a given element are similar to one another but different 
    from the atoms of other elements.

* Atoms of two or more elements combine to form compounds.

* A chemical reaction involves the rearrangement, seperation, or
   combination of atoms.

* Atoms are never created or destroyed during a chemical reaction.

Carbon

The element found in all living matter.

Bonds

Atoms combine chemically with one another in one of two ways, they form _____.

Chemical  ____ are formed when the outermost  electrons are transferred (gained or lost) or shared between atoms.

Compound

10 Common substances found in living systems

1.   Water

2.   Carbon dioxide gas

3.   Molecular oxygen

4.   Ammonia

5.   Mineral Salts

6.   Carbohydrates

7.   Lipids

8.   Proteins

9.   Nucleic Acids

10. Adenosine Triphosphate (ATP)

Water

The most abundant substance in living cells, approximately 60% to 80% of a cell is water; plasma, which is the liquid portion of blood, is 92% _____.

It has a number of roles in cells.  It takes part in some reactions, such as photosynthesis in plant cells, which supplies our earth with molecular oxygen, and respiration in both plant and animal cells, which produces energy.

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

Water Continued

It is part of amniotic fluid and protects the developing fetus.  It is also part of the cerebrospinal fluid and protects the brain and spinal cord by functioning as a shock absorber.

Finally, it is the base for all body lubricants such as mucus in the digestive tract and synovial fluid in joints.

Carbon Dioxide (CO₂)

A small molecule that contains one carbon atom covalently bonded to two oxygen atoms.  It is produced as a waste product of cellular respiration and must ne eliminated quickly from the body through expiration via the respiratory system and the cardiovascular system.

If ____ ____ is allowed to accumulate within the cells, it becomes toxic by forming carbonic acid as it reacts with water.  Hence we exhale it quickly from the lungs.

Molecular Oxygen (O₂)

Formed when two oxygen atoms are covalently bonded together, is required by all organisms that breath air.

*  It is necessary to convert chemical energy (food), such as the
    energy found in a glucose (C₆H₁₂O₆) molecule into another form
    of chemical energy, ATP, that can be used by cells to do work.
* Without plants there would be no molecular oxygen in
   our atmosphere, and without O₂ there would be no life on our planet
   as we know it.
*  The level of O₂ in our atmosphere is maintained at a nearly constant level (about 20% 
   of the gas in the atmosphere is oxygen) by the many different kinds of plants found 
   on our earth.

Hydrolysis

Digestion of food requires water to break down larger molecules, this is called ______.

Solvent

Water serves as a medium or ______ for other reactions, and water is referred to as a universal ______.

Ammonia (NH₃)

The ______ molecule comes from decomposition of proteins via the digestive process and the conversion of amino acids in cellular respiration to ATP molecules. An important element in _____ is nitrogen.

Because even a small amount of ____ is injurous to cells, the human body must quickly dispose of this material,

Through enzymes, the liver coverts the toxic ___ to a harmless substance called urea. Because urea is soluable in water, the blood then carries the urea to the kidneys to be filtered and eliminated from the body as urine.

Nitrogen

______ is an essential element in amino acids, which are the building blocks of proteins.

Mineral Salts

__ __ are composed of small ions. They are essential for the survival and functioning of the body's cells.

* Calcium (C_a⁺) is necessary for muscle contraction and nervous
   transmission as well as strong bones. It is the fifth most abundant
   element in the body.

* Phosphate (PO₄^-) is necessary to produce the high-energy molecule
   ATP.

* Chloride (CI^-) is necessary for nervous transmission.

* Sodium (N_a⁺) and Potassium (K⁺) are also necessary for muscle cell
   contraction and movement.

Know 

Carbohydrates

___ are made up of the atoms of carbon, hydrogen, and oxygen in a 1:2:1 ratio.

The smallest _____ are the simple sugars that cannot be made to react to water to produce a simpler form.

_____ have two important functions: energy storage (sugars, starch, glycogen) and cell strengthening (cellulose of plant cell walls and chitin in the external skeleton of arthropod animals).  Energy storage is the most common function.

Lipids

There are a number of different kinds of ____.

_____ are substances that are insoluable in water.  Fats, phosphoilipids, steroids, and prostaglandins are examples of these different kinds of molecules.

This book concentrates on fats which are a major kind of _____.

Of the fats in the human body, 95% are triglycerides, also called triacylglycerols.

Know 

Fats

A fatty acid is saturated if it contains only single covalent bonds such as those found in whole milk, butter, eggs,beef, pork, and coconut and palm oils.  Saturated fats tend to be solids at room temperature. Too much of these fatty acids contributes to cardiovascular disease.

If the carbon chain has one or more double covalent bonds between the carbon atoms, it is an unsaturated fatty acid.  These fatty acids are good for you and are found in sunflower, corn,  and fish oils. Unsaturated fats tend to be liquids at room temperature.

**Fat found under the skin acts as an insulator to prevent heat loss.  Fat also protects organs as a surrounding layer such as the layer around our kidneys.

Know 

Proteins

___ are composed of carbon, hydrogen, oxygen, and nitrogen covalently bonded.  Most ____ also contain sulfer. The basic building blocks of ___ are 20 amino acids.

Many are structural ___.  ___ are part of a cell's membranous structures: plasma membrane, nuclear membrane, endoplasmic reticulum, and mitochondria.

We could not move, talk, breathe, digest, or circulate blood without the ____s actin and myosin. Additionally, our immune system funtions because antibodies, which are ____ of a high molecular weight, are formed to combat foreign proteins called antigens that enter the body. Proteins are also a source of energy that can be broken down and converted to ATP.

Enzymes

Chemical reactions in cells would not occur in cells without the assistance of ____.

_____ are protein catalysts, which increase the rate of chemical reaction without being affected by the reaction.

Proteins are also a source of energy that can be broken down and converted to ATP just like carbohydrates and fats.

Nucleic Acids

Two very important ___ ____ are found in cells.

Deoxyribonucleic acid (DNA) is the genetic material of the cells located in the nucleus of the cell.

Ribonucleic acid (RNA) is structurally related to DNA. Two important types of RNA are messenger RNA and transfer RNA, which are important molecules necessary for protein synthesis.

Know

Adenosine Triphosphate (ATP)

Adenosine Triphosphate (ATP) is the high-energy molecule or fuel that runs the cell's machinery.  All the food we eat (which is a form of chemical energy) must be transformed into another form of chemical energy (ATP) that allows our cells to maintain, repair, and reproduce themselves.

Movement of materials into and out of cells

The plasma membrane of cells is a selectively permeable membrane.  This means that only selected materials are capable of getting into and out of cells.

The cell membrane is composed of an outer and inner layer of protein with a double phospholipid layer in between.  This chemical arrangement allows water to pass into and out of the cell with ease.

However water is not the only needed material needed for the cells survival.

Cells need food like sugars, amino acids to make proteins, and nutirents like the mineral salts. 

Materials Pass through the cell's membrane in three diffrent ways:

1. Diffusion
2. Osmosis
3. Active Transport

Diffusion

The movement of molecules through a medium from an area of high concentration of those molecules to an area of low concentration of those molecules.Temperature has an effect on diffusion. The higher the temperature, the faster the movement.

Ex: Chunk of Ice: low temperature keeps the molecules moving very slowly, so the water is in a solid state. As temperature increases the water moves to a liquid state.

An example of an important diffusion in the human body is the uptake of oxygen by the blood in the lungs and the release of carbon dioxide gas to the lungs from the blood.

Osmosis

A special kind of diffusion.  ____ pertains only to the movement of water molecules through a selectively permeable membrane (e.g. a plasma membrane) from an area of high concentration of water molecules (e.g. pure water) to an area of low concentration of water molecules (e.g. water to which a solute such as sugar or salt has been added).

Active Transport

Know

The effects of Osmosis on Red Blood Cells

Isotonic Solution (normal saline solution): the salt concentration outside the red blood cell equals the salt concentration inside the red blood cell, water molecules will pass into and out of the red blood cell at an equal rate.

Hypotonic Soultion (pure distilled water): where the water molecules are in a higher concentration outside the red blood cell, water will move into the red blood cell, causing it to swell and eventually rupture.

Hypertonic Solution (5% salt solution): where there is more water inside the red blood cell than in the solution, the red blood cell will shrival up or crenulate.

List three functions of fats in the human body.

1. Source of energy

2. Act as insulators

3. Protect organs

What two major roles do carbohydrates play in living cells?

1. Energy storage

2. Cell Strengthening

List four functions of proteins necessary for the function and survival of the human body.

1. Many are structural proteins. Proteins are part of a cell's membraneous
    structure.

2.Chemical reactions inside a cell allow a cell to function properly. These
   chemical reactions would not occur in cells without the assistance of
   enzymes. Enzymes are protein catalysts.

3. Our immune system functions because antibodies, which are proteins of
    a high molecular weight, are formed to combat foreign proteins called
    antigens.

4. Proteins are a source of energy that can be broken down and converted
    to ATP.

Know

Cell

The cell is the basic unit of biologic organization of the human body.

Although cells have different functions in the body, they all have certain common structural properties.

Cells vary in size and most cells are too small to be seen with the unaided eye.

Protoplasm

All cells are composed of _____, which is an aqueous collidal solution of carbohydrates, proteins, lipids, nucleic acids, and inorganic salts surrounded by a cell membrane.

Protoplasm is predominately water with organic compounds in a colloidal suspension and inorganic compounds in solution.

Organelles

Compounds within the protoplasm that are the building blocks of structures within the protoplasm.

____ that are common to all eukaryotic cells are the nucleus, the mitochondra, the endoplasmic reticulum, ribosomes, the Gogli apparatus, and lysosomes.

Nucleus

When observed under a microscope, the most prominent structure in the cell is the ____.

The ___, is the control center of the cell.

The protoplasm of the cell is subdivided into two sections:

1. Nucleoplasm: the protoplasm inside the nucleus.

2. Cytoplasm: the protoplasm outside the nucleus.

History of the cell theory

Cells were not observed until the invention of the first microscope in the mid-17th century. Robert Hooke, an Engish scientist built the first microscope and decribed the first cells.

Anton von Leeuvenhoek, a Dutch naturalist, observed tiny organisms in pond water.

Modern Cell Theory

1. Cells are the smallest complete living things-they are the basic
    units of organisms.

2. All organisms are composed of one or more cells in which all
    life processes occur.

3. Cells arise only from preexisting cells through the process of
    cell division.

4. All of today's existing cells are descendants of the first cells
    formed early in the evoluntionary history of life on earth.

Cell Membrane

All cells are surrounded by a cell membrane. The membrane is often called the plasma membrane or the plasmalemma.

Cytoplasm of the cell

The liquid portion of the cell is called protoplasm.  The protoplasm outside the nucleus is called cytoplasm; the protoplasm inside the nucleus is called the nucleoplasm. The main consituent of cytoplasm is water.

The Nucleus

The _____ is the most prominent structure in the cell.  It is clearly visible with a light compound microscope.

It is a fluid containing structure that is seperated from the cytoplasm by the nuclear membrane.

The ___ is the control center of the cell.

Lysosomes

Small bodies in the cytoplasm that contain powerful digestive emzymes to enhance the breakdown of cellular components.

They have three functions.

3 Functions of Lysosomes

1. They act in conjunction with stored food vacuoles. When a cell needs more emergy, a ___ will fuse with a stored food vacuole to break down the stored food into a more usable form that can go to a mitochondrian to be converted into ATP.

2. ____ act in the maintainance and repair of cellular components.  If a section of ER needs to be rebuilt, the ___ will break down the membrane into amino acids, fatty acids, glycerol, and so on and material that can be recycled to build new protein and phospholipids.

3. ___ also act as suicide agents in old and weakened cells. This process is known as autolysis.

Protein Synthesis

Proteins are essential to cellular function and structure.

Enzymes are protein catalysts (all chemical reactions in the cell require emzymes), and our immune system functions through the production of antibodies (large proteins) that attack foreign proteins (antigens).

Cilis and Flagella

___ and ___ are cellular organelles located on the cell surface.  They are composed of fibrils that protrude from the cell and beat or vibrate.

* In the human body the male sperm is propelled by a single beaing flagellum that assists
   it in reaching the female egg in the upper part of the fallopian tube where they unite
   and fertilize.

* Stationary cells, like those that line our respiratory tract, are covered with cilia on their
   free edge to move the mucus-dust package upward across the cell surfaces to bring this
   material to the throat to be swallowed and then discharged from the body.

*Although ___ and ___ are similar anatomically, a flagella is considerly larger than a
  cilium.

* Externally, these structures are hairlike protrusions from the cell membrane.