Transcript Biomolecules

Biomolecules
Acids, Bases, and pH
• The pH scale: Chemist devised a
measurement system called the pH scale to
indicate the concentration of H+ ions in a
solution.
Acids
• Acidic solutions contain higher
concentrations of H+ ions that pure water
and have a pH value below 7
• Strong acids tend to have pH values that
range from 1 to 3.
• The hydrochloric acid produced by the
stomach to help digest food is a strong acid.
Bases
• A base is a compound that produces
hydroxide ions (OH-) in solution
• Basic, or alkaline, solutions contain lower
concentrations of H+ ions than pure water
and have pH values above 7
• Ammonium is a strong base
Buffers
• The pH of the fluids inside human cells must
be kept between 6.5 and 7.5. If the pH is
lower or higher, it will affect the chemical
reactions that take place with cells.
• Buffers are weak acids or bases that can
react with strong acids or bases to prevent
sharp, sudden changes in pH
– Easy Balance?
Carbon Compounds
• Carbon is so interesting that a whole branch
of chemistry is set aside just to study carbon
compounds. (Organic chemistry)
• Carbon has 4 valence electrons
• Carbon can also bond with another carbon
atom!!!
• No other element comes close to matching
carbons versatility…
Macromolecules (biomolecules)
• Many of the molecules of living cells are so
large that they are known as
macromolecules (giant molecule)
• There are four groups of macromolecules in
living things
– Carbohydrates
– Lipids
– Nucleic acids
– Proteins
Carbohydrates (Carbs)
• Carbohydrates are compounds made-up of
carbon, hydrogen and oxygen usually in the
ratio of 1:2:1
• Living things use carbs as their main source
of energy.
• Single sugar molecules: monosaccharides
• Monosaccharides form polysaccharides
Lipids
• Lipids are made mostly from carbon and
hydrogen atoms
• Lipids are used to store energy
• Steroids are derived from lipids called
cholesterol.
• The common groups of lipids are
– Fats
– Oils
– Waxes
Nucleic Acids
(DNA & RNA)
• Nucleic acids are macromolecules containing
hydrogen, oxygen, nitrogen, carbon, and
phosphorus.
• Nucleic acids are polymers assembled from
monomers known as nucleotides.
– Nucleotides
• Sugar
• Phosphate
• Nitrogenous base
Nucleic acids
Nucleic Acids (DNA & RNA)
• Nucleic acids store and transmit hereditary,
or genetic information.
• There are two kinds of nucleic acids:
– RNA (Ribonucleic acid)
– DNA (Deoxyribonucleic acid)
Proteins
• Proteins are polymers of monomers called
amino acids
• There are 20 amino acids
• About 10 are essential and must be
consumed in the foods we eat in order to be
healthy!!!
– Vegetarians?
Amino Acids Build Proteins
Proteins
• Some proteins control the rate of reactions
and regulate cell processes
• Some form bone and muscle
• Others work as doors or elevators that
transport substances into or out of cells.
– Enzyme: insulin???
The End