Saturday, January 10, 2009
Fri-Day 2
AP Chem- we did two Raoult's Law problems: one in which the mole fractions and vapor pressures of two liquids are used to determine the vapor pressure of each component (from which you can calculate the total pressure simply by adding the partial pressures of each component) and then getting the mole fraction of each component in the vapor phase. These calculations are the quantitative basis of fractional distillation, a process by which the more volatile components of a mixture (WEAKER IMFA's) are separated from the less volatile components (STRONGER IMFA's) of the same mixture.
In the other problem, we used the vapor pressure lowering effect of adding a solute to a solvent to determine the molar mass of the solute.
One point of clarification that I will repeat on Monday and that you can read in the enhanced notes on Blackboard: we were GIVEN the grams of solute in the question and asked ONLY for the molar mass of the solute MEANING that we had to solve ONLY for the MOLES of solute (by using Raoult's Law) because if you find moles of solute and you already know the grams of solute, then you know the molar mass of the solute in grams per mole!
I used to detailed a formula in class by plugging in the known grams of solute; I should have (and DID do so in my own notes and thought process, which I ignored for whatever reason) just solved the simpler Raoult's Law formula for moles and then just used that value to divide into the given number of grams to get the molar mass in grams per mole. See the corrected solution in the notes on Blackboard.
Bio 6- We finished our lab discussion of the hydrolysis of starch by amylase
Then, we looked at the purpose and actions of the endocrine system, a system of glands that REGULATE/maintain homeostasis by causing relatively long-term or longer lasting changes (usually) in an organism as a result of signals/changes/cues from the environment (internal or external).
We saw that each gland secretes specific hormones directly into the bloodstream; each hormone can only bind to specific "target cells" that the hormone is made for. For example, insulin, secreted by the pancreas, can bind to specific cells in the liver because the protein receptors on those liver cells match the particular shape (lock and key) of the insulin hormone.
Once the hormone binds to the target cells, the target cells will produce particular chemicals or enzymes that helps the body to maintain homeostasis.
We saw that the pituitary gland, which is the master gland because it targets/controls all but one of the other endocrine glands, is directed/controlled by the hypothalamus. The hypothalamus is the nexus or connection between the nervous system, which is always sensing/monitoring the environmental changes of an organism, and the endocrine system.
The hypothalamus has many different cell receptors so it is able to monitor the levels of many of the body's key biochemicals and the hypothalamus will send a hormone/chemical signal to the pituitary if/when any of those biochemicals are in too high or too low a concentration.
The pituitary will then secrete the appropriate hormone so that the appropriate target cells/gland will secrete a substance to maintain homeostasis i.e. raise or lower the level of the deficient or excess chemical.
We then looked at the thyroid gland, which regulates the body's respiratory rate/metabolic rate.
The parathyroid glands, embedded in the four corners of the thyroid gland, regulate the level of calcium ions in the blood and bones.
We also began to discuss the all IMPORTANT concept of negative FEEDBACK, which is THE key feature of maintaining homeostasis.
For example, if the level of calcium ions in the blood is too low, the parathyroid glands will secrete a hormone (parathormone) that targets the BONE CELLS to release some of their stored calcium ions into the blood, thus RAISING the level of calcium ions back to a normal level. Once the normal level of calcium ions is back to normal (this is the "feedback" part!), that normal level of calcium ions in the blood CAUSES the parathyroid glands to STOP secreting its hormone (parathormone). That completes the feedback cycle and calcium homeostasis is maintained.
adrenals- adrenaline is secreted when a person is under high stress from the environment (internal or external) and causes a relatively quick increase in blood glucose, blood pressure, and overall metabolic rate so that the person can effectively fight or flee the situation.
adrenal glands also secrete hormones that regulate the concentration of water and sodium ions in the blood by targeting kidney cells.
We discussed the sex hormones secreted from the ovaries (females) and testes (males):
the menstrual cycle, involving the periodic thickening of the uterus and the maturation and release of an egg cell is regulated by pituitary hormones and ovary hormones (estrogen and progesterone); also, secondary sex characteristics develop as a result of the secretion of sex hormones: in females, breast development and skeletal changes such as the broadening of the pelvis occur; in males, testosterone causes more facial and body hair to grow and/or thicken, muscles to develop, the larynx to become thicker and more developed (deeper voice).
We then focused on the all-important negative feedback loop:
negative feedback is a key feature of the endocrine system that helps an organism maintain homeostasis. In general,
a deficiency of some substance "X" is monitored and detected by some gland "G"--> the gland then secretes a hormone "H" which targets specific cells which then are signaled to make more of substance "X" (increasing the level of substance "X" in the blood) so that there is no more deficiency; (now for the NEGATIVE feedback part) the normal/increased level of substance "X" in the blood causes gland "G" to STOP secreting hormone "H" (otherwise the level of substance "X" may get TOO HIGH!) thus completing the feedback loop and maintaining homeostasis.
Bio 7/8- we looked at the purpose and actions of the endocrine system, a system of glands that REGULATE/maintain homeostasis by causing relatively long-term or longer lasting changes (usually) in an organism as a result of signals/changes/cues from the environment (internal or external).
We saw that each gland secretes specific hormones directly into the bloodstream; each hormone can only bind to specific "target cells" that the hormone is made for. For example, insulin, secreted by the pancreas, can bind to specific cells in the liver because the protein receptors on those liver cells match the particular shape (lock and key) of the insulin hormone.
Once the hormone binds to the target cells, the target cells will produce particular chemicals or enzymes that helps the body to maintain homeostasis.
We saw that the pituitary gland, which is the master gland because it targets/controls all but one of the other endocrine glands, is directed/controlled by the hypothalamus. The hypothalamus is the nexus or connection between the nervous system, which is always sensing/monitoring the environmental changes of an organism, and the endocrine system.
The hypothalamus has many different cell receptors so it is able to monitor the levels of many of the body's key biochemicals and the hypothalamus will send a hormone/chemical signal to the pituitary if/when any of those biochemicals are in too high or too low a concentration.
The pituitary will then secrete the appropriate hormone so that the appropriate target cells/gland will secrete a substance to maintain homeostasis i.e. raise or lower the level of the deficient or excess chemical.
We then looked at the thyroid gland, which regulates the body's respiratory rate/metabolic rate.
The parathyroid glands, embedded in the four corners of the thyroid gland, regulate the level of calcium ions in the blood and bones.
We also began to discuss the all IMPORTANT concept of negative FEEDBACK, which is THE key feature of maintaining homeostasis.
For example, if the level of calcium ions in the blood is too low, the parathyroid glands will secrete a hormone (parathormone) that targets the BONE CELLS to release some of their stored calcium ions into the blood, thus RAISING the level of calcium ions back to a normal level. Once the normal level of calcium ions is back to normal (this is the "feedback" part!), that normal level of calcium ions in the blood CAUSES the parathyroid glands to STOP secreting its hormone (parathormone). That completes the feedback cycle and calcium homeostasis is maintained.
adrenals- adrenaline is secreted when a person is under high stress from the environment (internal or external) and causes a relatively quick increase in blood glucose, blood pressure, and overall metabolic rate so that the person can effectively fight or flee the situation.
adrenal glands also secrete hormones that regulate the concentration of water and sodium ions in the blood by targeting kidney cells.
We discussed the sex hormones secreted from the ovaries (females) and testes (males):
the menstrual cycle, involving the periodic thickening of the uterus and the maturation and release of an egg cell is regulated by pituitary hormones and ovary hormones (estrogen and progesterone); also, secondary sex characteristics develop as a result of the secretion of sex hormones: in females, breast development and skeletal changes such as the broadening of the pelvis occur; in males, testosterone causes more facial and body hair to grow and/or thicken, muscles to develop, the larynx to become thicker and more developed (deeper voice).
We then focused on the all-important negative feedback loop:
negative feedback is a key feature of the endocrine system that helps an organism maintain homeostasis. In general,
a deficiency of some substance "X" is monitored and detected by some gland "G"--> the gland then secretes a hormone "H" which targets specific cells which then are signaled to make more of substance "X" (increasing the level of substance "X" in the blood) so that there is no more deficiency; (now for the NEGATIVE feedback part) the normal/increased level of substance "X" in the blood causes gland "G" to STOP secreting hormone "H" (otherwise the level of substance "X" may get TOO HIGH!) thus completing the feedback loop and maintaining homeostasis.
In the other problem, we used the vapor pressure lowering effect of adding a solute to a solvent to determine the molar mass of the solute.
One point of clarification that I will repeat on Monday and that you can read in the enhanced notes on Blackboard: we were GIVEN the grams of solute in the question and asked ONLY for the molar mass of the solute MEANING that we had to solve ONLY for the MOLES of solute (by using Raoult's Law) because if you find moles of solute and you already know the grams of solute, then you know the molar mass of the solute in grams per mole!
I used to detailed a formula in class by plugging in the known grams of solute; I should have (and DID do so in my own notes and thought process, which I ignored for whatever reason) just solved the simpler Raoult's Law formula for moles and then just used that value to divide into the given number of grams to get the molar mass in grams per mole. See the corrected solution in the notes on Blackboard.
Bio 6- We finished our lab discussion of the hydrolysis of starch by amylase
Then, we looked at the purpose and actions of the endocrine system, a system of glands that REGULATE/maintain homeostasis by causing relatively long-term or longer lasting changes (usually) in an organism as a result of signals/changes/cues from the environment (internal or external).
We saw that each gland secretes specific hormones directly into the bloodstream; each hormone can only bind to specific "target cells" that the hormone is made for. For example, insulin, secreted by the pancreas, can bind to specific cells in the liver because the protein receptors on those liver cells match the particular shape (lock and key) of the insulin hormone.
Once the hormone binds to the target cells, the target cells will produce particular chemicals or enzymes that helps the body to maintain homeostasis.
We saw that the pituitary gland, which is the master gland because it targets/controls all but one of the other endocrine glands, is directed/controlled by the hypothalamus. The hypothalamus is the nexus or connection between the nervous system, which is always sensing/monitoring the environmental changes of an organism, and the endocrine system.
The hypothalamus has many different cell receptors so it is able to monitor the levels of many of the body's key biochemicals and the hypothalamus will send a hormone/chemical signal to the pituitary if/when any of those biochemicals are in too high or too low a concentration.
The pituitary will then secrete the appropriate hormone so that the appropriate target cells/gland will secrete a substance to maintain homeostasis i.e. raise or lower the level of the deficient or excess chemical.
We then looked at the thyroid gland, which regulates the body's respiratory rate/metabolic rate.
The parathyroid glands, embedded in the four corners of the thyroid gland, regulate the level of calcium ions in the blood and bones.
We also began to discuss the all IMPORTANT concept of negative FEEDBACK, which is THE key feature of maintaining homeostasis.
For example, if the level of calcium ions in the blood is too low, the parathyroid glands will secrete a hormone (parathormone) that targets the BONE CELLS to release some of their stored calcium ions into the blood, thus RAISING the level of calcium ions back to a normal level. Once the normal level of calcium ions is back to normal (this is the "feedback" part!), that normal level of calcium ions in the blood CAUSES the parathyroid glands to STOP secreting its hormone (parathormone). That completes the feedback cycle and calcium homeostasis is maintained.
adrenals- adrenaline is secreted when a person is under high stress from the environment (internal or external) and causes a relatively quick increase in blood glucose, blood pressure, and overall metabolic rate so that the person can effectively fight or flee the situation.
adrenal glands also secrete hormones that regulate the concentration of water and sodium ions in the blood by targeting kidney cells.
We discussed the sex hormones secreted from the ovaries (females) and testes (males):
the menstrual cycle, involving the periodic thickening of the uterus and the maturation and release of an egg cell is regulated by pituitary hormones and ovary hormones (estrogen and progesterone); also, secondary sex characteristics develop as a result of the secretion of sex hormones: in females, breast development and skeletal changes such as the broadening of the pelvis occur; in males, testosterone causes more facial and body hair to grow and/or thicken, muscles to develop, the larynx to become thicker and more developed (deeper voice).
We then focused on the all-important negative feedback loop:
negative feedback is a key feature of the endocrine system that helps an organism maintain homeostasis. In general,
a deficiency of some substance "X" is monitored and detected by some gland "G"--> the gland then secretes a hormone "H" which targets specific cells which then are signaled to make more of substance "X" (increasing the level of substance "X" in the blood) so that there is no more deficiency; (now for the NEGATIVE feedback part) the normal/increased level of substance "X" in the blood causes gland "G" to STOP secreting hormone "H" (otherwise the level of substance "X" may get TOO HIGH!) thus completing the feedback loop and maintaining homeostasis.
Bio 7/8- we looked at the purpose and actions of the endocrine system, a system of glands that REGULATE/maintain homeostasis by causing relatively long-term or longer lasting changes (usually) in an organism as a result of signals/changes/cues from the environment (internal or external).
We saw that each gland secretes specific hormones directly into the bloodstream; each hormone can only bind to specific "target cells" that the hormone is made for. For example, insulin, secreted by the pancreas, can bind to specific cells in the liver because the protein receptors on those liver cells match the particular shape (lock and key) of the insulin hormone.
Once the hormone binds to the target cells, the target cells will produce particular chemicals or enzymes that helps the body to maintain homeostasis.
We saw that the pituitary gland, which is the master gland because it targets/controls all but one of the other endocrine glands, is directed/controlled by the hypothalamus. The hypothalamus is the nexus or connection between the nervous system, which is always sensing/monitoring the environmental changes of an organism, and the endocrine system.
The hypothalamus has many different cell receptors so it is able to monitor the levels of many of the body's key biochemicals and the hypothalamus will send a hormone/chemical signal to the pituitary if/when any of those biochemicals are in too high or too low a concentration.
The pituitary will then secrete the appropriate hormone so that the appropriate target cells/gland will secrete a substance to maintain homeostasis i.e. raise or lower the level of the deficient or excess chemical.
We then looked at the thyroid gland, which regulates the body's respiratory rate/metabolic rate.
The parathyroid glands, embedded in the four corners of the thyroid gland, regulate the level of calcium ions in the blood and bones.
We also began to discuss the all IMPORTANT concept of negative FEEDBACK, which is THE key feature of maintaining homeostasis.
For example, if the level of calcium ions in the blood is too low, the parathyroid glands will secrete a hormone (parathormone) that targets the BONE CELLS to release some of their stored calcium ions into the blood, thus RAISING the level of calcium ions back to a normal level. Once the normal level of calcium ions is back to normal (this is the "feedback" part!), that normal level of calcium ions in the blood CAUSES the parathyroid glands to STOP secreting its hormone (parathormone). That completes the feedback cycle and calcium homeostasis is maintained.
adrenals- adrenaline is secreted when a person is under high stress from the environment (internal or external) and causes a relatively quick increase in blood glucose, blood pressure, and overall metabolic rate so that the person can effectively fight or flee the situation.
adrenal glands also secrete hormones that regulate the concentration of water and sodium ions in the blood by targeting kidney cells.
We discussed the sex hormones secreted from the ovaries (females) and testes (males):
the menstrual cycle, involving the periodic thickening of the uterus and the maturation and release of an egg cell is regulated by pituitary hormones and ovary hormones (estrogen and progesterone); also, secondary sex characteristics develop as a result of the secretion of sex hormones: in females, breast development and skeletal changes such as the broadening of the pelvis occur; in males, testosterone causes more facial and body hair to grow and/or thicken, muscles to develop, the larynx to become thicker and more developed (deeper voice).
We then focused on the all-important negative feedback loop:
negative feedback is a key feature of the endocrine system that helps an organism maintain homeostasis. In general,
a deficiency of some substance "X" is monitored and detected by some gland "G"--> the gland then secretes a hormone "H" which targets specific cells which then are signaled to make more of substance "X" (increasing the level of substance "X" in the blood) so that there is no more deficiency; (now for the NEGATIVE feedback part) the normal/increased level of substance "X" in the blood causes gland "G" to STOP secreting hormone "H" (otherwise the level of substance "X" may get TOO HIGH!) thus completing the feedback loop and maintaining homeostasis.
# posted by C @ 3:05 PM 
