Transcript Biological Molecules continued

My objectives:
The sub-questions :
1). What are the parts of a cell?
2). How do cells function?
3). How do cells make up organs?
4). What is a molecule?
5). What is the function of a molecule in a cell?
 An organelle is a specialized part of a cell; analogous to
an organ; "the first organelle to be identified was the
nucleus"
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 Defining characteristics of prokaryotic cells:
 - having cells that lack membrane-bound nuclei
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 Defining characteristics of Eukaryotic cells:
 - organism the cells of which have a defined nucleus and
internal membranes
What they look like
prokaryote
eukaryote
Definitions, details, and
how cells function
 Cell wall: A semi rigid, permeable structure that is composed of cellulose, lignin, or other
substances and that envelopes most plant cells.
www.epidemic.org/glossary/glossaryC/
The cell wall helps the cell keep its shape and acts as a protective barrier
 Cell Membrane: A thin membrane (a double layer of lipids) enclosing the cytoplasm of a
cell; proteins in the membrane control passage of ions (like sodium or potassium or
calcium) in and out of the cell. All cells have a cell membrane.
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ORGANELLES:
Lipid: An oily organic compound insoluble in water but soluble in organic solvents;
essential structural component of living cells (along with proteins and carbohydrates)
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Definitions and details
 Vacuole: A tiny cavity filled with fluid in the cytoplasm of a cell
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Plant vacuoles are filled with a fluid that contains nutrients and minerals, they act as large
cellular storage containers.
Lysosome: An organelle that contains hydrolytic enzymes, which can degrade biopolymers
such as DNA, RNA (nucleases), polysaccharides such as glycogen and starch (glycosidases),
protein (proteases), cell wall components and biomembrane components (phosphatases).
www.prism.gatech.edu/~gh19/b1510/cellglos.htm
Cytoplasm: The protoplasm of a cell excluding the nucleus; is full of proteins that control cell
metabolism.
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Plastid: Any of various small particles in the cytoplasm of the cells of plants and some
animals containing pigments or starch or oil or protein.
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Definitions and details
Chloroplast: Plastid containing chlorophyll and other pigments; in plants that carry out
photosynthesis.
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Nucleus: A part of the cell containing DNA and RNA and responsible for growth and
reproduction. ; The nucleus is a membrane bound structure that contains the cell's
hereditary information.
http://biology.about.com/od/cellanatomy/p/nucleus.htm
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Nucleolus: A small round body of protein in a cell nucleus; such organelles contain RNA
and are involved in protein synthesis.
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Protein Synthesis: The process by which amino acids are linearly arranged into proteins
through the involvement of ribosomal RNA, transfer RNA, messenger RNA, and various
enzymes.
http://dictionary.reference.com/browse/protein+synthesis
Definitions and details
Mitochondrion: An organelle containing enzymes responsible for producing energy.
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Endoplasmic reticulum: A system of folded membranes that loop back and forth,
spreading throughout the cytoplasm and providing a large surface area for cell reactions.
pubs.niaaa.nih.gov/publications/arh27-4/331-332.htm
Golgi Complex: A network of vesicles preparing hormones and other products for
secretion.
www.miracosta.edu/home/sfoster/neurons/glossary.htm
Definitions and details
 Dictyosome: The set of flattened membranes in a Golgi body, resembling a stack of
plates.
http://dictionary.reference.com/browse/Dictyosome
Ribosome: (an organelle in the cytoplasm of a living cell; they attach to mRNA and move
down it one codon at a time and then stop until tRNA brings the required amino acid;
when it reaches a stop codon it falls apart and releases the completed protein molecule
for use by the cell) "the ribosome is the site of protein synthesis
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There are four major groups of organic compounds that are commonly present in
the formation or structure of cells. These four chemical compound classifications
are: carbohydrates, lipids, proteins, and nucleic acids. These compounds
consist almost solely of carbon, hydrogen, and oxygen. Carbohydrates, lipids,
proteins, and nucleic acids are all compounds, or in a simpler sense, molecules.
Carbohydrates
A monomer, a simple part , of a carbohydrate is called a monosaccharide. These
monosaccharides are simple sugars – the most common of which are fructose,
sucrose and galactose. Sometimes a compound like a simple sugar can have several
slightly differing forms that all have an identical chemical formula, These different
forms are called isomers.
Sometimes it is possible for two simple sugars to come together in a
condensation reaction. When the two isomers come together they form what is
called a double sugar, or disaccharide. It is also a possible for these disaccharides to
combine, if there are three or more it may be called a polysaccharide.
Proteins
Proteins are organic compounds that are composed mainly of nitrogen, oxygen,
hydrogen, and carbon. Like other macromolecules, proteins are formed by the
bonding of other monomers with the appropriate composition. Many things such as
skin, muscle, and most organic catalysts are made of proteins.
The monomer building blocks of proteins are called amino acids. Most of these
amino acids share a common structure.
Two amino acids can bond to form a dipeptide in a condensation reaction.
These amino acids can bond to each other in a long chain to form what is commonly
called a polypeptide. These long chains can have hundreds of amino acids and their
shape is influenced by several factors such as hydrogen bonding and heat.
Enzymes are organic molecules that act as catalysts. Most enzymes are
proteins. These reactions depend on the fact that the enzyme and the reactant
molecule must be a precise fit for each other. This fitting is responsible for a slight
change in the shape of the enzyme.
This allows the enzyme to better conform to the shape of the reactant
molecule, and also is likely to weaken the molecule’s bonds and therefore make it
more reactive. Enzymes are unchanged after the reaction, therefore they can be
used many times over, it are also what releases the products of the reaction.
lipids
These organic molecules are large, nonpolar, and do not dissolve in water. These
molecules store energy more effectively than most others because they have a
higher number of carbon and hydrogen atoms in comparison to carbohydrates.
These store energy more efficiently than the carbon-oxygen bonds that are
commonly found in other organic compounds.
Fatty acids are long unbranched chains of carbon molecules that make up
most lipids. At one end of the chain there is a carboxyl group, COOH, this is
why the two ends of the chain have completely different properties. The
carboxyl end is polar and therefore wants to attach to water molecules. This
property makes the fatty acid molecule “hydrophyllic” or “water loving” the
other end of the fatty acid chain is non- polar, and therefore if “hydrophobic”
or water fearing. A saturated fatty acid is when all of the carbon molecules
have the maximum amount of bonds (4).
there are three important types of lipids in the world of biology.
These important groups are triglycerides, phospholipids, and waxes. A
triglyceride is a group of three fatty acid chains joined to a molecule of
alcohol or glycerol. Saturated triglycerides are only different by the fact that
they contain only saturated fatty acid chains. They tend to be solid at room
temperature, and have a high melting point.
Phospholipids have two rather than three fatty acid chains. They, also are
joined to a molecule of glycerol. Cell membranes are usually composed by two
layers of phospholipids.
A wax is a structural form of lipid. These wax molecules are a long chain of fatty
acid molecules bonded to a chain of alcohol. These are useful in biology because
waxes are highly waterproof, and in plants these waxes often form a protective outer
layer, they also often are found within protective inner membranes of animals.
Nucleic Acids
Nucleic acids are large and complex, they contain many individual particles.
These nucleic acids store a lot of important information about the cell. Computers
use binary code to convey information, nucleic acids use a similar concept .
Cells use a system of four different compounds to store their hereditary
information. These four compounds can be arranged in different orders in
order to act as a code for the genetic instructions of a cell. Deoxyribonucleic
acid (DNA) includes all of the information vital to cell function including the
information responsible for proper cell division. Ribonucleic acid of RNA
stores and transfers all of the information that is vital for producing proteins.
Both DNA and RNA are long polymers made of thousands of small monomers
called nucleotides. Each nucleotide consists of three components: a
phosphate group, a five-carbon sugar, and a ring shaped nitrogen base.
Most of the information in this section was derived from the “Modern Biology “ book.
Cellular respiration
Cellular respiration: The metabolic processes whereby certain organisms
obtain energy from organic molecules; processes that take place in the cells
and tissues during which energy is released and carbon dioxide is produced
and absorbed by the blood to be transported to the lungs.
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ATP A nucleotide derived from adenosine that occurs in muscle tissue; the

major source of energy for cellular reactions.
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WHAT IT ALL MEANS TO US
(earthlings)

Cells are a vital part of “spaceship earth” especially now when some of its systems
are failing to function properly. Cell theory states that all living organisms consist of
one or more cells, this means that if they have problems, knowing about them and
their functions is vital in trying to restore their proper function. This fascinating
concept of the cell- the huge amount of genetic information stored in it, and the fact
that it is able to function as a separate organism within an organism. These
magnificent structures are well evolved and adapted, but not invincible, therefore we
must be careful that nothing harms or alters our cells- that might not be that great.