Calcium and other minerals

Question 1

Calcium

Answer 1

most abundant mineral in bodies
98% of Ca in bodies is in complex with phosphorus (hydroxyapatite)

Question 2

calcium function

Answer 2

bone and teeth formation
nerve conduction
cell adhesion
cell signaling (calmodulin, GCPRs)
enzyme catalysis
DNA and protein structures

Question 3

Regulation of Calcium

Answer 3

serum levels (8-10 mg/dL)
found in 3 forms (albumin, salt, ionized)
ionized fraction is bioactive fraction
organs that regulate Ca are intestine, kidneys, parathyroid gland

Question 4

Calcium homeostasis

Answer 4

serum Ca2+ levels are regulated by 3 hormones (PTH, calcitriol, and calcitonin)
parathyroid glands trigger PTH which triggers calcitriol (also stimulates serum Ca increase) and serum Ca increase

Question 5

Calcium deficiency

Answer 5

hypocalcemia
- hypoparathyroidism
- vitamind D def
- cause osteoporosis, osteomalacia, rickets

Question 6

High Ca levels

Answer 6

trigger syn of thyroid hormone
trigger calcitonin
trigger bone reabsorption
decrease serum Ca levels

Question 7

high Ca levels

Answer 7

hypercalcemia
- hyperparathyroidism
- cancer
- may cause kidney stones

Question 8

Phosphorus

Answer 8

most abundant intracellular anion
85% of P in our bodies is in complex with Ca (hydroxyapatite)
also membranes, DNA, RNA, ATP

Question 9

Phosphorus functions

Answer 9

bone and teeth formation
enzyme PTM
cellular energy

Question 10

Regulation of Phosphorus

Answer 10

regulated by the kidneys together with calcium
P forms complexes with Ca that reduces the bioavailability of Ca

Question 11

Hyperphosphatemia

Answer 11

rare
caused by decreased PTH
metastatic calcification
soft bone problems

Question 12

Hypophosphatemia

Answer 12

rare
often due to refeeding syndrome
overuse of antacids
muscle weakness

Question 13

Magnesium

Answer 13

also abundant in body (25g)
605 OF Mg is teeth and bones

Question 14

Magnesium functions

Answer 14

bone and teeth formation
enzyme catalysis
protein structure
blood pressure regulation

Question 15

Regulation of Magnesium

Answer 15

homeostasis controlled by kidneys

Question 16

hypomagesemia

Answer 16

rare
due to impaired absorption or excessive excretion
can cause muscle and nerve hyper excitability and cardiac arrhythmias

Question 17

hypermagnesemia

Answer 17

hypotension
MgSO4 is used to treat preeclampsia

Question 18

Sodium and Chloride

Answer 18

primary extracellular electrolytes
we consume both in excess

Question 19

Sodium and Chloride functions

Answer 19

sodium required for intestinal absorption and renal reabsorption of glucose, galactose, and FAA
sodium intake increases water tension (and thus BP)
chloride required to make HCl
also important for acid-base balance

Question 20

Regulation of Sodium and Chloride

Answer 20

excreted by kidneys
sodium induces water retention (increases BP)

Question 21

Hyponatremia

Answer 21

Na < 135 mmoles/L
from headache to confusion and coma
mostly occurs when changes in blood volume, or excretion issues
often occurs during/after an endurance event
beer potomania

Question 22

Hypernatremia

Answer 22

Na > 155 mmoles/L
often as result of sweating, vomiting, diarrhea
often as result of sweating, vomiting, diarrhea, diuretics, or kidney disease
main problem often is dehydration or poor hydration

Question 23

Potassium

Answer 23

primary intracellular electrolyte
increase in dietary K could result in increased excretion of Na and lower BP
western diets do not provide enough K

Question 24

functions of potassium

Answer 24

regulation of fluid balance
muscle function
nerve function
thyroid function
pH balance

Question 25

Hypokalemia

Answer 25

rare
can result in muscle weakness, cramps, tingling
often due to diuretics, fluid loss

Question 26

Regulation of Potassium

Answer 26

regulated by renal excretion

Question 27

Hyperkalemia

Answer 27

rare
often due to excessive fluid loss
most common symptom is arrhytmia

Question 28

Copper

Answer 28

essential trace elements
toxic in high amounts
genetic diseases associated with this element

Question 29

Copper functions

Answer 29

aerobic respiration
transport of iron
destruction of free radicals

Question 30

Regulation of Copper

Answer 30

absorbed in intestine
transported and stored in liver
transport uses ceruloplasmin

Question 31

Copper
Menkes syndrome

Answer 31

x-linked disease
rare, affects males
export of Cu from enterocytes to liver impaired
Cu transport ATPase is mutated
systemic Cu def. observed
anemia occurs
urinary and serum Cu levels are low, as ceruloplasmin
progressive neurodegeneration also occurs
changes in hair are also observed
parenteral admin of CU may work

Question 32

Copper
Wilson disease

Answer 32

autosomal recessive disease
rare
export of Cu from liver to other tissues is impaired
Cu transport ATPase is mutated
excess Cu leakes into blood and accumulates in brain, eyes, kidneys and skin
hepatic, neurologic, and psychiatric problems are observed
can be treated with chelating agents

Question 33

Zinc

Answer 33

essential trace element
no particualr storage center

Question 34

functions of zinc

Answer 34

important for protein structure and catalysis
important for immune system

Question 35

Regulation of zinc

Answer 35

absorbed through transporter
phytates binds Zn irreversibly and block its absorption

Question 36

Chromium MOA

Answer 36

potentiates action of insulin

Question 37

fluorine

Answer 37

added to water in many countries
it replaces the Oh in hydroxyapatite and makes it more resistant to acids (helps to prevent cavities)

Question 38

Idoine

Answer 38

added to salt in many countries around world
required for TH synthesis
hypothyroidism
- major cause of intellectual disability in children
- causes slower metabolism, weight gain, fatigue, depression
hyperthyroidism
- affects metabolism, behavior and heart rate

Question 39

Selenium

Answer 39

required for 25 humans proteins
AA selenocysteine
involved in elimination of free radicals
can cause deficiencies and can be toxic