| Question | Answer |
|---|---|
| Explain why the nervous system is compared to an airmail delivery system. | Nervous system uses rapidly propagated electrical "messages" |
| Explain why the endocrine system is compared to the pony express. | Endocrine system "messages" (hormones) are released into the blood to travel much more slowly to target organs. |
| Define hormone | a chemical substance released into the blood which alters "target cell" metabolism in a specific way |
| What two molecular groups do hormones belong to? | steroids and amino acid based molecules |
| What do all hormones have in common? | they are all chemical molecules that have specific target organs and that are reached via blood. |
| Define target organ. | Organ responding to a particular hormone in a specific way. |
| If hormones travel in the bloodstream, why don't all tissues respond to all hormones? | The proper "hormone" receptors must be present on the plasma memebrane or within the cells for the tissue cells to respond. |
| What is located in the throat; bilobed gland connected by an isthmus? | thyroid gland |
| What is found close to the kidney? | adrenal gland |
| What is a mixed gland, located close to the stomach and small intestine? | pancreas |
| What is a paired glands suspended in the scrotum? | testes |
| What rides horseback on the thyroid gland? | parathyroids |
| What is found in the pelvic cavity of the female, concerned with ova and female hormone production? | ovaries |
| What is found in the upper thorax overlying the heart; large during youth? | thymus |
| What is found in the roof of the 3rd ventricle? | pineal body |
| What is the hormone and the site of production for programming of T lymphocytes? | thymosin and site: thymus |
| What is the hormone and the site of production that are released in response to stressors? | cortisone and adrenal cortex; epinephrine and adrenal medulla |
| What hormone and site of production for regulation of blood calcium levels? | calcitonin and thyroid gland; PTH and parathyroid glands |
| What is the hormone and the site of production for the drive of development of secondary sexual characteristics? | estrogens and ovaries; testosterone and testes; ACTH and anterior pituitary; FSH and anterior pituitary; LH and anterior pituitary |
| What is the hormone and site of production that regulates the function of another endocrine gland? | TSH and anterior pituitary |
| What is the hormone and the site of production that mimics the sympathetic nervous system? | epinephrine and adrenal medulla |
| What is the hormone and site of production that regulates blood glucose levels; produced by the same "mixed" gland? | glucagon and pancreas; insulin and pancreas |
| What is the hormone and site of production that is directly responsible for regulation of the menstrual cycle? | estrogens and ovaries; progesterone and ovaries |
| What is the hormone and the site of production for the maintenance of salt and water balance in the extracellular fluid? | ADH and hypothalamus; aldosterone and adrenal cortex |
| What is the hormone and the site of production that is directly involved in milk production and ejection? | oxytocin and the hypothalamus; prolactin and anterior pituitary |
| How does the hypothalamus control both anterior and posterior pituitary functioning? | Produces "releasing and inhibiting hormones" which control the production and release of anterior pituitary hormones; forms hormones ADH and oxytocin, which are transported to the posterior pituitary then released on nervous stimulation from hypothalamus |
| How is the hormone ADH stimulated? | the nervous system |
| How is the hormone aldosterone stimulated? | humoral factors (the concentration of specific nonhormonal substances in the blood or extracellular fluid) |
| How is the hormone estrogen stimulated? | another hormone |
| How is the hormone insulin stimulated? | humoral factors |
| How is the hormone norepinephrine stimulated? | the nervous system |
| How is the hormone parathyroid hormone stimulated? | humoral factors |
| How is the hormone t4/t3 stimulated? | another hormone |
| How is the hormone testosterone stimulated? | another hormone |
| How is the hormone TSH, FSH stimulated? | the nervous system |
| What does PTH produce if inadequate amounts are released? | tetany |
| What is a hormone? | 1. Produced by glandular tissue 2. Enters interstitial space3. Enters vascular system 4. Goes to a target tissue |
| How many intercellular messenger types are there? | six |
| What is the 1st intercellular messenger type? | Hormones |
| What is the 2nd intercellular messenger type? | Neurotransmitter |
| What is the 3rd intercellular messenger type? | Neurohormone |
| What is the 4th intercellular messenger type? | Paracrine cells – influence local tissues |
| What is the 5th intercellular messenger type? | Autocrine cells – self influencing |
| What is the 6th intercellular messenger type? | Pheromones – released into the environment |
| How do hormones work? | 1. Amplitude modulated signal – conc time period 2. Frequency modulated signal – short bursts used up rapidly |
| What two categories do hormones fall into? | Lipid and Water based. |
| What kind of life expectancy does lipid based hormones have? | longer half life |
| What kind of life expentancy does water based hormones have? | shorter half life |
| What is half life? | amount of time it takes to break down 50% of the substance |
| What is one way of prolonging half life? | conjugation – done by the liver binding hormones with proteins |
| What is the 1st way that we can influence the release of hormones? | Humoral – (inside the body)Ion conc can influence release of hormones, blood sugars |
| What is a 2nd way that we can influence the release of hormones? | Nervous System – stress, neurohormones |
| What is a 3rd way that we can influence the release of hormones? | Hormonal – hormone to hormone influence |
| What are the two types of receptors? | intramembraneous- hormones influence the cell by activating the membrane and intercellular receptor which takes place in the cell (up and down regulation) |
| What does the pituitary gland connect to? | hypothalamus |
| What is the hypothalamus part of? | diencephalons |
| What does the hypothalamus do? | it regulates the release of hormones by the pituitary gland (master gland) |
| What does the hypothalamus secrete? | It secretes releasing or inhibiting hormones to pituitary gland. |
| What does the hypothalamohypophyseal portal system connect to? | hypothalamus to ant. pit. |
| What does the hypothalamohypophyseal nerve tract connect to? | hypothalamus to the post. pit. |
