Transcript Carbon Compounds in Cells - Page County Public Schools

Carbon Compounds in Cells
What is Organic Chemistry?
• Is the chemistry that deals with element
carbon and one or more elements.
• All living organisms are made up of
carbon-hints why we study it in biology.
• Examples of organic compounds are:
– Protein, Nucleic Acid, Carbohydrates, and
Lipids
• Methane is the simplest organic
compound
Carbon Bonding
• Carbon and the other elements are
bonded covalently
• Oxygen, hydrogen, Nitrogen, Sulfur and
carbon are most abundant elements in
living matter
• Carbon can share pairs of electrons with
as many as four other atoms to form
organic molecules of several configuration
• Much of H and O is linked to form water
Functional Groups
• Are atoms or groups of atoms covalently
bonded to a carbon backbone, they covey
distinct properties, such as solubility and
chemical reactivity, to the complete
molecule.
Know P. 38
You will have a quiz on this.
Date: Friday,
February 4, 2011
Four Families of Building Blocks
• Simple sugars, fatty acids, amino acids,
and nucleotides
• Monomers can be joined to form larger
polymers.
• Enzymes-is a class proteins that make
metabolic reactions proceed faster
Ten Categories of Reactions
• 1- Functional Group transfer from one
molecule to another
• 2- Electron transfer- stripped from one one
molecule to another
• 3- Rearrangement of internal bond
converts one type of organic molecule to
another
Continue…
• 4- Condensation- two molecules to one
• 5- Cleavage- one molecule into two
• 6- Hydrolysis - break down compounds by
adding water
• 7- Dehydration - two components brought
together, produces H2O
• 8- Endergonic - requires the input of
energy
• 9- Exergonic - releases energy
• 10- Redox - electron transfer reactions
Condensation Reaction
• One molecule is stripped of its H+, another
is stripped of its OH-; then the two
molecule fragments join to form a new
compound and the H+ and OH- form
water.
• Example: Starch formed by repeat
condensation reaction
Hydrolysis
• Is the reserve: one molecule is split by the
addition H+ and OH- (from water) to the
components (condensation in reserve)
• Hydrolysis cleave polymer into smaller
molecules when required for the building
blocks for energy
Carbohydrates: Most Abundant
element of life
• Made up of carbon, oxygen and hydrogen
in a set proportion of 1:2:1
• Monosaccharides (Simple Sugar)
– They are characteristics by solubility in water,
sweet taste, and several –OH
• Examples:
• Glucose and Fructose: Used assembling larger
carbohydrate
Glucose
Carbohydrates: Continue
• Disaccharides: Consists of two
monosaccharides joined together through
the process of dehydration synthesis
(which removes water in the process)
– Examples: Lactose (Glucose + Galactose)
Present in Milk (dehydration synthesis)
– Sucrose (glucose + Fructose) is transported
form of sugar used by plants and harvested
by humans for use in food
– Continue Examples:
– Maltose (two glucose) is present in
germinating seeds
• Pentoses: 5 carbon sugar
– Deoxyribose (sugar for DNA)
– Ribose (sugar for RNA)
Complex Carbohydrates
• Polysaccharides are macromolecules,
polymers with few hundred to a few
thousand monosaccharides joined
together.
– Examples: Starch: Plant storage for energy;
unbranched coil chain and easily hydrolyzed
– Cellulose: Found in plants for structure
(insoluble)
– Glycogen: (animal cell storage)
– Chitin: polymer of glucose (arthropods
exoskeleton)
• Continue Examples
– Glycogen: High branched used by animals to
store energy in muscles and liver.
• Is also converted to blood sugar when blood sugar
drops
– Chitin: polysaccharide with nitrogen attached
to glucose monomers which gives arthropods
exoskeleton
Lipids
• A large biological molecules that does not
consist of polymers.
• Lipids are greasy or oil compounds with
little tendency to dissolve in water
(hydrophobic)
• Can be broken down by hydrolysis
reaction
• Function: energy storage, membrane
structure and coatings
Continue: Lipids
• Fatty Acids
– Fatty Acid: is a long chain of mostly carbon
and hydrogen atoms with a –COOH group at
one end
Continue..
• When they are part of complex lipids, the
fatty acids resemble long flexible tails
– Unsaturated fats: fats are liquids (oils) at room
temperature because one ore more double
bonds between the carbons in the fatty acids
permits “kinks” in the tails
– Example: Fish Oil
Unsaturated Fats 
• Saturated fats: (triglycerides) have a single C-C
bonds in their fatty acid tails and are solids at
room temperature
•
•
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They are tightly packed together
Solid at room temperature
Examples: Butter and Lard
Diets rich in saturated fat leads to cardiovascular
disease
– Triglycerides: “neutral” fats most abundant lipids
and the richest source of energy
Fats
• Are constructed from two kinds of smaller
molecules: Glycerol and fatty acids
– They are a rich source of energy, yielding
more than twice the energy per weight basis
as carbohydrates
– Provides an insulation blanket for animals to
endure the harsh cold temperatures
Phospholipids
• Formed from 2 fatty acids + phosphate
group attached to glycerol
• Provide structure support in membranes
where they are arranged in bilayers
Steroids
• Have lipid characteristics by a carbon
skeleton consisting of four fused rings
• Example: Cholesterol: common
component of animal cell membranes and
is also the precursor from which other
steroids are synthesized (Example:
vertebrate sex hormones)
Waxes
• They are formed by attachment of long
chains of fatty acids to long chains
alcohols or carbon rings
• Function: serve as coatings on plant parts
and animals coverings
Amino Acids
• Are the building blocks of proteins
• Contain a amino group, carboxyl group
and one of twenty varying R groups
• Covalently bonded to a central carbon
atom
Protein
• Function as enzymes, in cell movements, as
storage, and transport agents (hormones,
antibodies, and structural material)
• Amino acids are the building blocks of
proteins (peptide bonds)
– Amino acids coil into a 3D structure
– Heat can denatured proteins causing a change
in shape and the ability to work properly
• Enzymes: special protein used to speed up
a chemical reaction (biological catalyst)
Polypeptide Formation (2 to 3 amino acids)
Primary Structure
• Primary structure is defined as ordered
sequences of amino acids each linked
together by peptide bonds to form
polypeptide bonds
• The sequence of amino acids to
determined by DNA and is unique for each
kind of protein
Continue: Secondary structure
• Fibrous Proteins (beta pleated) : have
polypeptide chains organized as strands
or sheets
– Contribute to the shape, internal organization,
and movement of cells.
• Globular Proteins (alpha helix): have
chains folded into compact rounded
shapes
– Example: Enzymes
– Keratin
Secondary Structure
• Helical coil shape (e.g. Hemoglobin) or
sheetlike array (as in silk) that results from
hydrogen bonding of side groups on the
amino acids chains.
Tertiary Structure
• Is the result of folding due to interactions
among R groups along polypeptide chain
Quaternary Structure
• Two or more polypeptide chains
• Hemoglobin- four interacting chains that
form a globular protein
• Keratin and collagen– complex fibrous
proteins
Glycoproteins
• Consist of olgosaccharides covalently
bonded to proteins
• Abundantly found in exterior of animal
cells and blood
• Lipoproteins: have both lipid and protein
components
– Transport fats and cholesterol in the blood
Denaturation
• High Temperature or changes in pH can
cause a loss of protein’s normal 3-D shape
• Pineapple
– Fresh vs Canned and Jello
Why is protein so important?
• Alternation of a cell’s DNA can result in the
wrong amino acid insertion in a
polypeptide chain
– Example: If valine is substituted for glutamate
in hemoglobin, the result is HbS (Sickle Cell
Anemia)
• Person who inherit two mutated genes for the beta
chain of hemoglobin can make HbS
• Causes a person blood to be shaped like a sickle
not a round disk
Nucleotides and Nucleic Acid
• Nucleotides consists of a: 5 carbon sugar
(ribose or deoxyribose), a nitrogen base,
and phosphate group
– Adenosine phosphate are chemical
messenger (cAMP) or energy carriers (ATP)
– Nucleotide coenzyme transport hydrogen
atoms and electrons (example NAD+ and
FAD)
– Nucleotides serve as a building block for
nucleic acid
Nucleic Acid
• Are polymers of nucleotides
– Four different kinds of nucleotides are strung
together to form large single or doublestranded molecules
– Each strand’s backbone consists of joined
sugars and phosphates with nitrogen bases
projecting toward interior
DNA vs RNA
• DNA
– 2 strand
– 5 carbon sugar:
Deoxyribose
– Nitrogen bases:
Adenine, Thymine,
Cytosine, Guanine
– Inheritance
• RNA
– 1 strand
– 5 carbon sugar:
Ribose
– Nitrogen Bases:
adenine, uracil,
cytosine, guanine
– Protein Synthesis