Transcript Chapter 2 : The Chemistry of Life Section 3 : Carbon

CHAPTER 2: THE CHEMISTRY OF LIFE
SECTION 3: CARBON COMPOUNDS
CCS Biology
Mr. Bogusch
The Chemistry of Carbon
• Organic Chemistry – study of chemistry that contain bonds
between carbon atoms
• Carbon can bond with many elements, including hydrogen,
oxygen, phosphorus, sulfur, and nitrogen to form the
molecules of life
The Chemistry of Carbon
•Characteristics of carbon
• Carbon has 4 valence electrons – meaning it can make up to 4
covalent bonds with itself or many other elements
• Carbon can bond with itself in a single, double, or triple
covalent bond
The Chemistry of Carbon
•Macromolecules
• Macromolecules – “giant
molecules” --molecules made from
hundreds to thousands of smaller
molecules
• Polymerization – process by which
large compounds are formed by
joining smaller ones together
• Monomers – one molecule or
“single part”
• Polymers – many molecules or
“many parts”
Four Major Groups of Macromolecules
(found in living things)
Carbohydrates
Proteins
Biological
Macromolecules
Nucleic
Acids
Lipids
Four Major Groups of Macromolecules
(found in living things)
Carbohydrates
•Carbohydrates
• Carbohydrates – compounds made up of carbon, hydrogen,
and oxygen atoms usually in a ratio of 1:2:1
• Living things use carbohydrates as their main sources of
energy. Plants, some animals, and other organisms also use
carbohydrates for structural purposes.
• The breakdown of glucose provides immediately energy
for cell activities
• Starches – extra sugar stored as complex carbohydrates
Four Major Groups of Macromolecules
(found in living things)
Carbohydrates
• Simples Sugars
• Monosaccharides – single sugar molecules
• For example: Glucose, fructose (found in fruit), galactose
(found in milk)
• Disaccharide – two monosaccharides (single sugars) joined
together
• For example: Sucrose (disaccharide) if made by joining
glucose and fructose.
Simples Sugars
Four Major Groups of Macromolecules
(found in living things)
Carbohydrates
• Complex Carbohydrates
• Polysaccharides – large molecules formed from joining
monosaccharides
• Animal Carbohydrates
• Glycogen - (animal starch) is formed by joining many glucose
monosaccharides together
• Glycogen supplies energy for muscle contraction
• Plant Carbohydrates
• Starch – polysaccharide that plants use to store sugar
• Cellulose – fibrous polysaccharide plants use for strength and
rigidity
• Cellulose is the main component of wood and paper
Four Major Groups of Macromolecules
(found in living things)
Carbohydrates
Carbohydrates
Four Major Groups of Macromolecules
(found in living things)
Lipids
Lipids
• Lipids – nonpolar molecules that cannot dissolve in water and
made of mostly carbon and hydrogen atoms
• Lipids can be used to store energy. Some lipids are important
parts of biological membranes and waterproof coverings.
• Steroids (which include hormones) are lipids
Hormones - chemical messengers
Four Major Groups of Macromolecules
(found in living things)
Lipids
Four Major Groups of Macromolecules
(found in living things)
Lipids
• Lipids are made of a glycerol molecule and fatty acid tails
• Saturated fatty acid – the fatty acid tail is completely filled with
hydrogen atoms
• Fats that are solid at room temperature
• Butter, grease
• Polyunsaturated fatty acid (unsaturated) – the fatty acid tail
has at least ne carbon – carbon double bond
• Fats that are liquid at room temperature
• Olive oil, corn oil canola oil, peanut oil
Four Major Groups of Macromolecules
(found in living things)
Lipids
Four Major Groups of Macromolecules
(found in living things)
Nucleic
Acids
Nucleic Acids
• Nucleic Acid – macromolecules that contain nucleotides
• Nucleotides – molecule that has a nitrogenous base, 5-carbon
sugar, and a phosphate group.
• ATP – adenosine triphosphate – chemical energy in organisms
ATP
Nucleotide
Four Major Groups of Macromolecules
(found in living things)
• Hereditary information – DNA and
RNA
• Nucleic Acids store and
transmit hereditary, or genetic
information
• Ribonucleic Acid – RNA transfer the instructions to
build proteins from the
nucleus to ribosomes
(where proteins are built)
• Deoxyribonucleic Acid –
DNA - have the instructions
to build proteins
Nucleic
Acids
Nucleic Acids - DNA
Four Major Groups of Macromolecules
(found in living things)
Nucleic
Acids
Four Major Groups of Macromolecules
(found in living things)
Proteins
Proteins
• Protein – macromolecules that are made of chains
(polymers) of amino acids
• Proteins are assembled by RNA from the instructions of
DNA
• Amino acids – compounds with an amino group (NH2) on
one end and a carboxyl group (COOH) on the other end.
• Peptide bonds (covalent bonds) link amino acids
together.
Four Major Groups of Macromolecules
(found in living things)
Proteins
Proteins DO EVERTHING!!!!
• Some proteins control the rate of reactions and regulate cell
processes. Other proteins from important cellular structures,
while others transport substances into or out of cells to help fight
disease.
Four Major Groups of Macromolecules
(found in living things)
• Structure and Function
• There are around 20 different
amino acids found in nature
• Amino acids are diverse
macromolecules – some are
acidic and some are basic,
some are polar and some are
nonpolar (meaning some will
dissolve in water and some
will not)
Proteins
Four Major Groups of Macromolecules
(found in living things)
Proteins
Four Major Groups of Macromolecules
(found in living things)
Chapter 2: Science of Biology
Section 4: Chemical Reactions and
Enzymes
Chemical Reactions
• Chemical reaction – process
that changes, or transforms,
one set of chemicals into
another
• Mass and energy are
conserved during the reaction
• The law of conservation of
energy states that energy
may neither be created nor
destroyed.
1. As it enters the blood, carbon dioxide (CO2) reacts with water to
produce carbonic acid (H2CO3), which is highly soluble.
2. This chemical reaction enables the blood to carry carbon dioxide to
the lungs.
3. In the lungs, the reaction is reversed and produces carbon dioxide
gas, which you exhale.
Chemical Reactions
• Reactants – elements or compounds that enter the chemical
reaction
• Products – elements or compounds produced by the chemical
reaction
• Chemical reactions involve changes in the chemical bonds that
joins atoms in compounds
Chemical Reaction Example
Energy in Reactions
• Chemical reactions that release energy often occur on their own,
or spontaneously.
• For example: burning of hydrogen gas
• 2H2 + O2 -- 2H2O
Hindenburg
Energy in Reactions
• Chemical reactions that absorb energy will not occur without a
source of energy
• Activation Energy – energy needed to start a chemical reaction.
Enzymes
• Catalyst – a substance that speeds up the rate of a chemical
reaction
• Enzyme – Proteins that speed up chemical reactions by reducing
the activation energy (amount of energy needed to start the
chemical reaction)
• Enzymes are biological catalyst
Enzymes
• The Enzyme- Substrate Complex
• Substrate – the substance an enzyme acts on
• The reactants of enzyme-catalyzed reactions
• Active site – the site on the enzyme where that substrate binds
onto.
• Similar to a “lock and key”
• Control (regulation) of
Enzyme Activity
• Temperature, pH, and
other molecules can
affect the activity of
enzymes
• For example: Human
enzymes work best at
a temperature of 37°C
(98.6°F).
• Human enzymes
in the stomach
work best at a pH
of 2