Card Set Information

2012-04-11 22:55:57
jaime doakes fortis bio 207

ch 4-5
Show Answers:

  1. What is the sum of an organism's chemical reactions called?
  2. Why is protein synthesis important?
    Special types of proteins called enzymes control the rate of each chemical reaction.
  3. What is the anabolic process that joins small molecules by releasing the equivalent of a water molecule?
    Dehydration Synthesis
  4. What is enymatically adding a water molecule to split a milecule?
  5. How do enzymes control metabolic reactions?
    Most enzymes are globular proteins that catalyze specific chemical reactions in cells by lowering activation energy required to start these reactions.
  6. Steps of an enzyme-catalyzed reaction:
    1. Active sites temporarily combine with portions of the substrate, forming an enzyme-substrate complex. 2. This interaction strains chemical bonds in the substrate in a way that makes a particular chemical reaction more likely to occur. 3. When it does, the enzyme is released in its original form, able to bind to another substrate molecule.
  7. What is part of an enzyme that temporarily binds to a substrate?
    Active site
  8. An enzyme that controls the rate of a metabolic pathway by regulating one of its steps. This stabilizes the rate of production and prevents under or over production of a product:
    rate-limiting enzyme
  9. How does ATP store chemical energy and make it available to a cell?
    • Each ATP molecule consists of 3 main parts:
    • An adenine, a ribose, and 3 phosphates in a chain. The 2nd and 3rd phosphate are attached by a high-energy bonds, and the chemical energy stored in one or both may be quickly trasnferred to another molecule in a metabolic reaction. The energy held in the bonds are released when broken, giving energy to the cell.
  10. Explain the importance of the oxidation of glucose:
    The energy released by oxidation of glucose is harnessed to promote cellular metabolism.
  11. What are rare distinctions in DNA sequences that alter health or appearance?
  12. How can mutations cause disease?
    • 1. When an enzyme is lacking from a metebolic pathway, childgood strage diseases result
    • 2. A protein may have altered function (cystic fibrosis/cickle cell anemia)
    • 3.A protein may be produced in excess ( In Epilepsy, excess GABA can lead to increased norepinephrine/dopamine)
  13. What are SNP's (pronounced snips)-
    • Single Nucleotide Polymorphisms-more common genetic variants with no detectable effects.
    • Polymorphism means many forms.
  14. 2 ways mutations originate:
    • Spontaneously due to the chemical tendency of free nitrogenous bases to exist in 2 slightly different structures.
    • Induced-a response to exposure to a certain chemical or radiation.
  15. How is glucose stored rather than broken down?
    Following a meal, when glucose concentration is relatively high, liver cells obtain glucose from the blood and synthesize glycogen.
  16. What is a gene?
    Part of a DNA molecule that encodes the information to synthesize a protein, a control sequence, or tRNA or rRNA. The unit of inheritance.
  17. What is a genome?
    Complete set of genetic instructions for an organism.
  18. What is a genetic code?
    Information for synthesizing proteins encoded in the nucleotide sequence of DNA molecules.
  19. What is transcription?
    Manufacturing a complimentary RNA from DNA.
  20. What is translation?
    Assembly of an amino acid chain according to the sequence of base triplets in an mRNA molecule.
  21. Name 3 types of genetic changes.
    • SNP's.
    • Mutations.
    • Inborn errors of metabolism.
  22. Describe a tissue and explain the intracellular junctions found in tissues.
    • Tissues-similar cells that are specialized to perform a common function.
    • Tight-junctions-zipper-like junctions that prevent extracellular leakage.
    • Desmosomes-hold adjacent cells, and therefore hold the layer of cells together.
    • Gap-junctions-channels between cells for passage of substances and impulses.
  23. How are glands classified?
    • By their secretory actions-endocrine secretes product into tissue fluid/blood; exocrine glands secrete product into ducts that open to surfaces.
    • By their number of cells-unicellular/multicellular.
    • By the way the duct branches-simple/compound.
    • Shape-tubular/alveolar.
    • How they secrete hormones-(merocrine release fluid products by exocytosis.)
  24. What is the major function of Areolar connective tissue?
  25. What is the major function of Adipose connective tissue?
    protection/energy store
  26. What is the major function of Reticular connective tissue?
  27. What is the major function of dense regular connective tissue?
  28. What is the major function of dense irregular connective tissue?
    tensile strength
  29. What is the major function of elastic connective tissue?
    durability with stretch
  30. What is the major function of hyaline cartilage?
  31. What is the major function of fibrocartilage?
    shock absorber
  32. What is the major function of elastic cartilage?
    shape maintenance plus flexibility
  33. What is the major function of bone?
    support, hematopoiesis
  34. What is the major function of blood?
    transport of nutrients, waste, and gas
  35. Describe and locate Serous membranes:
    • Found in CLOSED ventral body cavities.
    • Visceral or Parietal.
    • Slippery, soapy-looking watery fluid.
    • Lungs, heart, and abdominal organs.
    • Protects.
  36. Describe and locate Mucous membranes:
    • Line body cavities OPEN to outside.
    • Lines digestive, respiratory, and urinary tract.
    • Consists of a layer of epithelium (varies depending upon location)
  37. Describe and locate Cutaneous membranes:
    • SKIN:
    • Layers of keratinized stratified squamous ET firmly attached to a thick layer of dense irregular CT.
  38. Describe and locate synovial membranes:
    • Composed entirely of CT.
    • Lines joints.
  39. Explain how protein is synthesized.
    • Transcription-
    • A) Occurs in nucleaus of the cell.
    • B) DNA strands unwind and the H-bonds between the strands are broken; only one of the exposed templates of the DNA molecule is used to build the mRNA strand. RNA nucleotides (within the nucleus) into a strand. The mRNA can now leave the nucleus and travel to the ribosomes (the protein synthesis machinery.
    • Translation-
    • A) Occurs at ribosomes that are either free in the cytoplasm or attached to ER.
    • B) Can only start at START CODON A-U-G.
    • C) tRNA molecules bring appropriate amino acids for each codon to the ribosome. The tRNA has an ANTICODON which is complimentary to the codon on the mRNA strand.
    • D) Two codons of mRNA are read in the ribosome at the same time. tRNA molecules deliver their amino acids to the ribosome, and a peptide bond is formed between adjacent amino acids. mRNA molicule is read codon by codon, with each corresponding amino acid being added to the chain of amino acids.