Biology and Human Concerns
09/30/09 – Notes
-Amino acid monomers
(Diagram bottom of page 42 – amino group vs. carboxyl group)
-Linked by dehydration synthesis
-Link formed by carbon and nitrogen – peptide bond
-polypeptide = protein = bond forms polypeptide chain
-Order of polypeptides determines what type of amino acid is formed,
fold into 3-Dimensional shape to do different jobs.
-Cells build proteins, programmed by genes
-Primary structure: beginning of all of the shaping of the protein
sequence of amino acids forms correct proteins
-Secondary structure: (diagram page 45). Alpha helix forms weak
hydrogen bonds that hold spiral shapes
-Denaturation occurs when body temperature
gets too high, because proteins begin unfolding
-Tertiary structure: Stronger bonding helps protein hold shape.
(Living cell in living thing = surrounded by water).
-Loops and folds give protein shape
-Hyrophobic ends cluster in the middle, hydrophilic
ends face the outside around water
-Quaternary Structure: tertiary structures “glued” together in the cell by
collagen. 2 or more polypeptide subunits. 4
connected form a haemoglobin molecule.
- Structural proteins: attach things together (cells to cells, parts of the
body to other parts of the body.
-Transport proteins: control what gets into cell and what doesn’t.
regulate movement within cell.
-Defensive proteins: antibodies: bind to invaders (pathogens) and
mark them for destruction.
-Enzymes: changes the rate of another chemical reaction
-Sensory proteins: (“living things respond to change in environment”!).
-Gene regulatory proteins: bind to DNA and control whether genes will
be read. Proteins do things to other proteins to give them function
-Nucleic acids are long chains of monomers.
-Made of three parts: sugar, nitrogen base (shape made of carbon and
nitrogen) and a phosphate group. (ex. Deoxyribonucleic acid, ribonucleic acid)
RNA – Ribose = sugar. bases. Adenine, guanine, cytosine, uracil
DNA – Deoxyribose = sugar. bases. Adenine, guanine, cytosine and thymine