bio exam

• Pre-synaptic


  Before the synapse
• Post-synaptic


  After the synapse
• Agonist


  Substance that binds to a receptor and activates it
• Antagonist


  Substance that binds to a receptor and blocks its activation
• Hormones


  Travel through the bloodstream; seconds to hours
• Neurotransmitters


  Travel between neurons to transmit a nerve impulse, faster
• Endocrine system


  • Hypothalamus
  • Direct neural control
  • Direct release of hormones
  • Indirect control through release of regulatory hormones
• 3 main classes of hormones

  • Amino acid derivatives (e.g. Melatonin)
  • Polypeptides (e.g. Vasopressin)
  • Steroids (e.g. Estradiol)
• Steroids


  Get inside cell; hydrophobic
• Karyotype


  Definition and image of eukaryotic chromosomes
• Cells


  • Somatic cells
  • Reproductive cells (gametes)
• Somatic cells


  Have 2 matched sets of chromosomes; diploid (2n)
• Gametes (eggs and sperm)

  Have half the number of chromosomes and are haploid (1n)
• Homologous pairs


  Chromosomes that are the same
• Heterologous pairs


  Chromosomes that are different
• Stages of interphase


  • G1
  • S
  • G2
• Chromosomes are visible in prophase
• Checkpoint


  Goal is to prevent going to the next phase without errors or damage
• Proto-oncogenes


  Normal genes that code for positive cell cycle regulators
• Oncogene


  Damaged cancerous gene
• Somatic cells


  Go through mitosis
• Gametes


  Go through meiosis
• Meiosis makes 4 identical haploid cells in the last stage</b>
• Meiosis makes identical copies, mitosis does not