Reading...
Play button
Play button
Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
26 Cards in this Set
- Front
- Back
|
exocytosis
secretion contraction contractility |
Calcium triggers _________ of chemical messengers, stimulates ________ of various substances, stimulate muscle ________, and increases the __________ of the heart and blood vessels.
|
|
|
hypercalcemia
|
An increase in plasma calcium, called __________, has widespread effects on the body, including muscle weakness and atrophy, lethargy, behavioral changes, hypertension, constipation, and nausea.
|
|
|
hypocalcemia
|
A decrease in plasma calcium, called __________, causes numbness and tingling sensations, muscle cramps and spasms, exaggerated reflexes, hypotension.
|
|
|
kidneys
digestive tract bone skin |
What organs of the body regulate plasma calcium concentration?
|
|
|
digestive tract
bone kidneys |
Calcium can be added to the plasma from bone and absorbed via the ________ _____, and it can be removed from the plasma by ____ and the _______.
|
|
|
reservior
resorption |
The bone provides a ________ of calcium such that when plasma calcium levels are low, the plasma can obtain calcium via a process called _________, during which bone is broken down to liberate calcium ions.
|
|
|
deposited
|
When the plasma calcium levels are high, calcium can be _________ into bone.
|
|
|
carrier proteins
free |
Calcium is transported in blood both bound to ______ _______ and _____ in the plasma.
|
|
|
glomerulus
|
Calcium that is free in the plasma is freely filtered at the _________.
|
|
|
reabsorbed
|
Normally, 99% of the filtered calcium is ________ as the tubular fluid moves through the renal tubules.
|
|
|
proximal tubules
distal tubules |
Approximately 70% of the filtered calcium is reabsorbed in the _______ _______, 20% is reabsorbed in the thick ascending limbs of the loops of Henle, and the remaining 10% is reabsorbed in the ______ _______.
|
|
|
hormones
|
Reabsorption in the loops of Henle and the distal tubules is regulated by ________.
|
|
|
PTH
Calcitriol Calcitonin |
What are the hormones that regulate plasma calcium levels? (3)
|
|
|
PTH
|
___ is the primary regulator of plasma calcium levels.
|
|
|
PTH
|
peptide hormone
produced in the parathyroid glands secreted in response to a DECREASE in the plasma calcium concentration. |
|
|
reabsorption
excretion calcitriol kidneys increases |
PTH stimulates calcium __________ in the ascending limb of the loop of Henle and the distal tubules, which decreases the _________ of calcium and sustains plasma calcium levels; (2) stimulates the activation in the kidneys of _________, which stimulates calcium absorption in the digestive tract and calcium reabsorption in the ______; and (3) stimulates resorption of bone, which ________ plasma calcium levels.
|
|
|
PTH
|
___ also directly causes a small increase in the absorption of calcium from the digestive tract.
|
|
|
Calcitriol
|
steriod hormone
increase plasma calcium levels by stimulating calcium reabsorption in the distal tubules of the kidneys. synthesize from vit. D3 which can be synthesized from 7-dehydrocholesterol in the skin upon exposure to sunlight, or absorbed from the diet. D3 travels to the liver, where it is converted to 25-hydroxyvitamin. Then it travels in the bloodstream to the kidneys, where, in response to low plasma calcium levels, PTH regulate the conversion of 25-OH D3 to _________. |
|
|
Calcitonin
|
decreases plasma calcium levels
peptide hormone secreted from C cells in thyroid gland Triggered by increases in plasma calcium levels Increase bone formation by depositing calcium Decreases reabsorption of calcium by the kidneys, which leads to increase in urinary excretion of calcium Decrease plasma calcium levels. |
|
|
ADH
sodium Na+/K+ pumps sodium secretion late distal tubules & collecting ducts water reabsorption |
___, which in addition to increasing water reabsorption also stimulates production of ______ channels in the principal cells, thereby enhancing the movement of sodium ions from the tubule lumen into these cells. As more sodium enters the cell, the ______/________ _____ works faster to rid the cell of _______, increasing sodium reabsorption and potassium ________. ADH also decreases water flow to the ____ ______ _______ and ________ _____ because less water is left following its reabsorption. The decrease in the _____ increases solute concentration in the tubules, which affects the ___________ or secretion of any solutes present in these tubules
|
|
|
angiotensin II
ANP |
__________ increases ADH secretion, which stimulates water reabsorption, ___ inhibits ADH secretion, which decreases water reabsorption.
|
|
|
venous return
decrease MAP baroreceptors PNS BV |
Hemorrhage results in a ↓ in BV, which ↓ _______ _______. With less blood returning to the heart, SV ↓, causing a ________ in _____. This ↓ in MAP is detected by atrial ___________, which activate the SNS & inhibit the ____. This results in an ↑ of HR and SV, and an ↑ in total peripheral resistance. All of which ↑ MAP. This is a rapid process and doesn't correct the problem of the loss of ____.
|
|
|
renin
afferent baroreceptor reflex kidneys vasoconstriction Adrenal cortex sodium water plasma volume |
↓ in MAP stimulates ______ secretion both directly and indirectly. ↓ ________ arteriole pressure which stimulates renin secretion. The ___________ ______ ↑ sympathetic input to juxtaglomerular cells, which stimulate renin secretion. ↑ renin secretion from the _______ ↑ plasma angiotensin II levels, producing effects that ↑ MAP. It leads to ______________, which ↑ TPR and MAP. It causes a stimulation of the _______ _______ to release aldosterone, which ↑ ______ reabsorption in the kidneys, which ↑ ______ reabsorption. Angiotensin II also stimulates thirst, which ↑ fluid intake and _______ ________.
|
|
|
ADH
reabsorption |
↓ activity in venous and cardiac baroreceptors stimulates ___ release from post. pit. ADH ↑ water ___________ in the kidneys, conserving plasma volume.
|
|
|
decrease
decease |
A _________ in MAP _________ GFR, which conserves sodium and water.
|
|
|
plasma
MAP kidneys erythrocytes |
Hemorrhage includes loss of ________ and blood cells. The blood cells are replaced by new cells. The ↓ in ____ results in a ↓ in blood flow to the kidneys, so O2 is ↓ to the _______, & erythropoetin is stimulated. This stimulates the production of new ___________.
|
