Chapter 10

  1. Mutations altering a protein's amino acid sequence can result in...
    Phenotypes ranging from insignificant to lethal
  2. Enzymes facilitate biochemical reactions by
    chemically converting substrates to products
  3. In cells, enzymatic reactions are interconnected to form chains of reactions called...
    biochemical pathways
  4. What is metabolism
    The sum of all biochemical reactions occurring in a cell; biochemical reactions are metabolic pathways
  5. Substrate of the blocked reaction may accumulate to toxic levels resulting in...
    1. An abnormal phenotype

    2. Or an essential enzyme required to produce a molecule needed for some cellular function is lost
  6. In early 20th century, Sir Archibald Garrod proposed that....
    1. Human genetic disorders and metabolism are related

    2. Patients with alkaptonuria lacked the enzyme to carry out specific biochemical reactions= inborn errors of metabolism
  7. Humans cannot synthesize____ essential amino acids, including phenylalanine
    9, thus we obtain these 9 from our diet
  8. Where does the phynylalanine that we consume go?
    2/3 is converted to tyrosine and 1/3 is recycled into protein construction
  9. Phenylketonuria results from...
    a mutation that prevents conversion of Phe into Tyr

    *individuals with PKU build up high levels of Phe and its derivatives that can result in mental retardation, neurological disorders, seizures, etc.
  10. Disorders stem from genes that affect...
    1. lipid metabolism

    2. nucleic acid metabolism

    3. carbohydrate metabolism
  11. Hemoglobin is...
    an iron-containing protein in RBC's that transports O2 from the lungs to the cells of the body
  12. *a protein's amino acid sequence determines its 3D structure and function

    4 levels of protein structure:
    1. Primary: linear amino acid sequence in polypeptide chain

    2. Secondary: 3D configurations that result from interactions between amino acids' NH and CO groups

    3. Tertiary: folding of secondary structure back on itself

    4. Quaternary: interactions between two or more polypeptide chains
  13. Hemoglobin is composed of four protein molecules called...

    *Each globin contains an iron-containing heme group
  14. Each adult hemoglobin molecule is made of...
    2 alpha globins and 2 beta globins
  15. pseudogenes
    nonfunctional copies of genes whose nucleotide sequence is similar to the functional gene, but mutations prevent their expression
  16. Genetic disorders of HbA fall into 2 categories:
    1. Hemoglobin Variants: production of molecules with changes in the amino acid sequence of the globin polypeptides

    2. Thalassemias: characterized by imbalances in globin synthesis
Card Set
Chapter 10
From Proteins to Phenotype