Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

GEMS > Minerals > Flashcards

Minerals Flashcards

1
Q

Calbindin-D

A

Ca++ absorption in the intestine involves a viatmin D-induced intracellular Ca++ binding protein

Binds Ca++ once in the cytosol – keep inside the cell at rock bottom levels– Maintain steep gradient

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Calmodulin

A

Most common Ca++ binding proteins in our cells
1. binds four calcium ions
2. Calmodulin changes conformation, resulting in an active complex
3. Two globular “hands” of the complex wrap around a binding site on a target protein

Essential allosteric activator of other proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Absorption of Ca++ occurs primarily in …

A

the duodenum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What two ion channels are involved in the absorption?

A

TRPV5 (transient receptor potential 5) & TRPV6

TRPV6»>TRPV5

TRPV5 mostly Ca++ DCT/PCT tubules of the kidney

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

TRPV5 expression

A

Highly induced by vitamin D (as calcitriol active hormone)

Lack of expression when vitamin D is low –>forces body to draw upon bone reserves —> low vitamin D – weak bones

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

PMCA1b

A

Basolateral Ca++-ATPase protein (active transport)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

NCX1

A

Antiporter – 3Na+ for each outgoing Ca++

Not active, depend on Na+ gradient established by Na+/K+-ATPase – secondary active transport

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

Albumin

A

Binds calcium in serum, can not pass through the kidneys

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Calcitriol

A
  1. Active form of vitamin D
  2. Role –> increase Ca++ levels in the blood
  3. stim bone resorption
  4. Intestinal Ca++ absorption
  5. Renal Ca++ reabsorption
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

PTH

A
  1. Role –> increase serum Ca++ and decrease serum Pi
  2. Increase bone resorption
  3. Increase renal Ca++ reabsorption
  4. Decrease renal Pi reabsorption

NO EFFECT on INTESTINAL Ca++ absorption

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Calcitonin

A
  1. Role –> decrease blood Ca++
  2. Inhibit bone resorption
  3. Renal Ca++ reabsorption
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Hypocalcemia causes?

A

Hypoparathyroidism (Wilson disease, thyroidectomy, Primary PTH deficiency, autoimmune destruction of parathyroid)

Low vitamin D (insufficient sunlight, low dietary intake, malabsorption, kidney disease)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

Hypercalcemia causes?

A

Primary Hyperparathyroidism (excess PTH)
Cancer (bone mets)
Vitamin D toxicity

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

Hypocalcemia presentation?

A
  1. Bone density disorders (rickets, osteomalacia, osteoporosis)
  2. Neuromuscular tetany, spasms, cramping
  3. Bronchospasms, laryngospasms
  4. Cardiomyopathy, prolonged QT interval
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

Hypercalcemia presentation

A
  1. Soft tissue calcification
  2. EKG abnormalities, chronic Ca++ overload can lead to permanent damage
  3. N/V, anorexia
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What stimulates 1alpha-Hydroxylase

A

Hormonal regulation of serum calcium levels

Low blood Ca++ stimulates –> PTH–>activates 1alpha-hydroxylase in kidney

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

1alpha-Hydroxylase function

A

Enzyme converts inactive form of Vitamin D (Cholecalciferol) into the active form (Calcitriol)

More potent than PTH in increasing serum Ca++

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Acrodermatitis Enteropathica

A

Zn malabsorption disorder resulting in deficiency of SLC39A4 (encoding the ZIP4 protein)

Sx: skin rashes, slowed growth/development, immune deficiencies

Vision problems are also possible because Zn is involved in Vitamin A metabolism

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

ATP7A

A

Cu-ATPase –> actively transports Cu1+ across the basolateral membrane

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

ATP7B

A

Cu-ATPase protein

Affected by Wilson’s Disease–> impairs efflux of Cu from cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

Calcium Roles

A

Divalent cation (Ca++) with high charge density

Signaling molecule (second messenger)

Regulates activity of Calmodulin

Cofactor of blood clotting enzymes – THROMBIN

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Ceruloplasmin

A

An additional Ferroxidase

Secreted by the LIVER and circulates in the blood

Helps to oxidize Fe++ –> Fe+++ for efficient loading onto Transferrin for transport

Also carries COPPER

23
Q

Copper

A

Key component of several enzymes that play critical functions in body

Necessary for proper iron metabolism: Required cofactor for FERROXIDASE enzymes

24
Q

Copper Transporter-1 (Ctr1)

A

Transports Cu+1 into enterocytes

Cu2+ atoms will be reduced to Cu1+ by Dcytb at luminal membrane so it can transport Ctr1

25
Q

Divalent Metal Transporter-1 (DMT-1)

A

Transporter protein takes up non-heme iron

Can only recognize Fe++ so to take up Iron in gut Fe+++ must be reduced to Fe++ (Dcytb reduces)

26
Q

Duoudenal Cytochrome b (Dcytb)

A

Cell surface enzyme responsible for reducing Fe+++ into Fe++

(aka Ferrireductase)

27
Q

Fenton reaction

A

Fe++ can participate in this reaction to produce the highly damaging hydroxyl radical

H2O2 + Fe++ –> Fe+++ + OH- OH*

28
Q

Ferritin

A

Storage protein for excess Fe+++ iron

Prevents excess iron so that it cannot cause damage to the cell

29
Q

Ferroportin

A

Fe++ transport protein on the basolateral membrane of the cell

(infants & adult)

30
Q

Heme Carrier Protein (HCP)

A

Heme receptor for receptor-mediated endocytosis

Intestinal lumen receptor

31
Q

Heme Oxygenase

A

Enzyme that “releases Fe++ from heme —> oxidizes Fe++ to Fe+++

32
Q

Hepcidin

A

Protein that functions to protect pts from absorbing too much iron

Binds to Ferroportin causing its internalization and destruction in lysosomes of intestinal cells

Produces and secreted by LIVER

Iron deficiency causes a suppression of HEPCIDIN expression in LIVER —> less hepcidin present to inhibit ferroportin function

33
Q

Hephaestin (Heph)

A

Ferroxidase enzymes

Involved in oxidation of Fe++ to Fe+++ required for intracellular storage (Ferritin) and transport in the blood (Transferrin)

34
Q

Lactoferrin (multiple roles) 1/2

A

Protein secreted in breast milk that enhances iron absorption in growing babies

Complexes with Fe+++ taken up by enterocytes via receptor mediated endocytosis

ALSO a transcription factor –> stim expression of growth hormone, cytokines and other molecules that help infant grow

35
Q

Lactoferrin (multiple roles) 2/2

A

Transcription factor that controls genes involved in INNATE & ADAPTIVE immunity, affording infant a high degree of protection

ALSO tight binding to IRON deprives bacteria/pathogens that they need to grow

36
Q

Macrominerals

A

Required by adults in relatively amounts (>100 mg/day)

ie. Calcium

37
Q

Menkes Syndrome

A

Risk factor for Copper deficiency

Caused by genetic deficiency of ATP7A. Impairs Cu absorption into body.

Rare X-linked disease

Sx: Kinky hair disease due to strange effect that Cu deficiency has on hair structure

38
Q

Metallothionein

A

Binds to Cu tightly in enterocytes, preventing absorption into the body

Metallothionein-bound Cu is eventually lost in stool once enterocytes are sloughed off

39
Q

Microminerals

A

Required by adults in trace amounts (1-100 mg/day)

ie. Copper

40
Q

Phosphorous

A

Free phospate (Pi=HPO4 2-) most abundant intracellular anion in cells

Highly diverse roles: DNA/RNA, ATP/GTP, Enzyme regulation (phosphorylation

41
Q

Thymulin

A

Zn dependent hormone involved in T-cell differentiation and maturation

(role of immune signaling pathway/cell differentiation)

42
Q

Transferrin (Tf)

A

Major iron-transporting protein present in the blood

Binds Fe+++»>Fe++

43
Q

Ultratrace Minerals

A

<1 mg/day

ex: Moybdenum

44
Q

Wilson’s Disease

A

High copper levels damage the parathyroid —> Hypoparathyroidism —> Hypocalcemia

Cu overload disease

AR disorder
Defects in Cu-ATPase protein ATP7B

Results in impaired efflux of Cu from cells; causes Cu accumulation in liver (esp**), eyes, brain, kidney, skin

Sx: Cog impairment, loss of motor function, liver failure

Tx with Zinc supplementation & chelation therapy

45
Q

Zinc roles

A

Structural role in Zinc finger-containing transcription factors – bind DNA and regulate gene transcription —NO SUBSTITUES

Involved in storage and secretion of insulin by pan Beta-cells

Immune signaling pathway & immune cell differentiation

Hundreds of enzymes require Zn for their activities (ADH, Carbonic Anhydrase, Prophobilinogen synthase, Superoxide Dismutase)

46
Q

ZIP4 (gene: SLC39A4)

A

Majority of Zn enters enterocytes through this transporter

47
Q

ZIP5

A

Transport protein – Zn exits enterocytes

It ZIP5 out

47
Q

SLC39A4 gene

A

Encodes ZIP

48
Q

Zinc supplementation

A

Tx for managing Wilson’s disease

Zinc induces the production of protein called Metallothionein in intestinal cells

Binds Cu tightly in enterocytes for excretion in stool

49
Q

Zinc Deficiency

A

Proteins will not assume their normal structures – compromising the regulation of numerous genes

Insulin secretion is compromised

50
Q

Alcohol dehydrogenase (ADH)

A

Enzymes, which oxidize ethanol to acetaldehyde in the liver and other tissues

51
Q

Carbonic Anhydrase

A

Involved in the blood bicarbonate buffer system

52
Q

Porphobilinogen Synthase

A

An enzyme of the heme biosynthesis pathway

53
Q

Surperoxide Dismutase (SOD)

A

Non-mitochondiral isoform, involved in elimination of superoxide

GEMS (20 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2025 Bold Learning Solutions. Terms and Conditions