BIOL 252 Exam 2- Endocrine, Skeletal, Muscular Rated 100% Correct!!

How are the amino acid-based and the steroid hormones different from each other (e.g. chemical properties; transport in the blood; interactions with target cells)? - Amino acid hormones: water soluble, unbound in blood, short duration effect, needs second messenger to send signal to nucleus for transcription Steroid hormones: lipid soluble, bound in blood to protein carriers for transport, prolonged effect I gave one example of a second messenger in the voicethread. Try to find another example. How is the latter regulated by hormones? - Second messenger example: cAMP Second example: DAG What are the interactions between the hypothalamus and the posterior pituitary gland? How is the "message" transmitted? - Hypothalamus secretes hormones (either ADH or Oxytocin) from hypothalamic nuclei down axons to the axon terminals of the posterior pituitary gland where they are stored or transported to the blood What are the interactions between the hypothalamus and the anterior pituitary gland? How is the "message" transmitted? - Hormones are secreted from the hypothalamus then sent directly to the anterior pituitary via the hypophyseal portal system. These hormones can either cause a increase/decrease in hormone synthesis of anterior pituitary, hormones are then secreted into the blood Surgical removal of the posterior pituitary gland in experimental animals results in marked symptoms, but the symptoms associated with hormone shortage are temporary. Explain these results. - Anterior secretion is separated from pituitary so anterior eventually compensates for loss of pituitary? Except for water retention regulation and oxytocin? Hypothalamus will compensatebecause anterior is synthesizer of hormones-not posterior Mr. Hoops has a son who wants to be a basketball player almost as much as Mr. Hoops wants him to be one. He knows a little bit about growth hormone and asks his son's doctor if she would prescribe some for his son, so he can grow taller. What do you think the Doctor tells Mr. Hoops? - Short term GH increase can be prescribed because the epiphyseal plates are still open----in people with dwarfism orthat have a deficiency in GH. BUT in a healthy person, increase in GH would upset homeostatic imbalance of glucose levels and could become fatal, thus the Doctor would not prescribe these What is the stress response? - "Fight or Flight" chemical preparation where both the SNS and the adrenal medulla work together to prepare for reaction to stress(injury, anxiety etc.) Cortisol increases glucose levels in the blood (via catabolism) and represses the immune system Steps: 1. Hypothalamic nuclei produce CRH 2. CRH goes to anterior gland via portal system, stimulates anterior to produce ACTH 3. ACTH secreted to blood 4. Receptor cells in adrenal cortex responds by producing Cortisol(stored in liver and muscles as glucose) 5. EX: cortisol goes to adipose tissue signals lipid breakdown into fatty acids 6. EX: muscle to promote protein breakdown into amino acids 7. EX: liver to promote glucose production