Minerals MODULE Biochemistry PDF/ PPT

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Minerals MODULE
Biochemistry

11

MINERALS Notes

11.1 INTRODUCTION
Minerals are indispensable part of a complete diet of farm animals. In this unit,
dietary essential minerals functions, factors affecting the requirements and
sources will be discussed. Minerals are essential for the normal growth and
maintance of the body. If the daily requirement is more than 100mg/day they are
called major elements and if the daily requirements is less than 100mg/day they
are called minor elements. The roles of minerals and vitamins in the maintenance
of homeostatic balance and mediation of metabolic reactions in the skeleton,
tissues, body fluids, digestive juices, etc.

OBJECTIVES
After reading this lesson, you will be able to:

classify minerals
describe the functions, Daily requirements of minerals

11.2 CALCIUM
Total calcium in the human body is 1 to 1.5kg, out of which 99% is seen in bone
and 1% in extracellular fluid. The main source of calcium is milk. But in India
cereals is major source of calcium. The daily requirement of calcium for child
is 1200mg/day and for adult it is 500mg/day. During pregnancy /lactation the
calcium requirement is 1500mg/day.

The absorption of calcium takes place in 1st and 2nd part of deuodenum. Calcium
absorption requires carrier protein, helped by Ca2+ – dependent ATpase.

Factors responsible for increase in calcium absorption include Vitamin D,
Parathyroid hormone, acidity and amino acids. Factors such as phytic acid,oxalates,

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Biochemistry malabsorption syndromes and Phosphates decreases calcium absorption. The
normal calcium level in blood is 9-11mg/dl.

11.2.1 Function of Calcium
The major functions of calcium are

(a) Excitation and contraction of muscle fibres needs calcium. The active
Notes transport system utilizing calcium binding protein is called Calsequestrin.

Calcium decreases neuromuscular irritability.
(b) Calcium is necessary for transmission of nerve impulse from presynaptic

to postsynaptic region.
(c) Calcium is used as second messenger in system involving protein and

inositol triphosphate.
(d) Secretion of insulin, parathyroid hormone, calcium etc, from the cells

requires calcium.
(e) Calcium decrease the passage of serum through capillaries thus, calcium

is clinically used to reduce allergic exudates.

(f) Calcium is also required for coagulation factors such as prothrombin.
(g) Calcium prolongs systole.
(h) Bone and teeth contains bulk quantity of calcium.

11.2.2 Factors regulating blood calcium level
The factors regulating the blood calcium level includes

(i) Vitamin D
(a) Vitamin D and absorption of calcium:

Active form of calcium is calcitriol. Calcitriol enters intestinal wall and
binds to cytoplasmic receptor and then binds with DNA causes depression
and consequent transcription of gene code for calbindin. Due to increased
availability of calbindin, absorption of calcium increases leading to
increased blood calcium level.

(b) Vitamin D and Bone:
Vitamin D activates osteoblast, bone forming cells & also stimulates
secretion of alkaline phosphatase. Due to this enzyme, calcium and
phosphorus increase.

(c) Vitamin D and Kidney:
Calcitriol increase reabsorption of calcium and phosphorus by renal
tubules.

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(ii) Parathyroid hormone (PTH) Biochemistry

Normal PTH level in serum is 10-60ng/l.

(a) PTH and bones:
In bone, PTH causes demineralization. It also causes recreation of
collagenase from osteoclast leads to loss of matrix and bone resorption.
As a result, mucopolysacharides and hydroxyproline are excreted in urine.

(b) PTH and Kidney: Notes

In kidney, PTH causes increased reabsorption of calcium but decreases
reabsorption of phosphorus from kidney tubules.

(iii) Calcitonin
Calcitonin decreases serum calcium level. It inhibits resorption of bone. It
decreases the activity of osteoclasts and increases osteoblasts.

11.2.3 Hyper Calcemia
When plasma Ca2+ level is more than 11mg/dl is called Hypercalcemia. It is due
to parathyroid adenoma or ectopic PTH secreting tumor. In this condition,
calcium excreted in urine decreases excretion of chloride causing hyperchloremic
acidosis. The main symptoms of hyperchloremic acidosis are:
(a) Anorexia, nausea,vomiting
(b) polyuria, polydypsia

(c) Confusion, depression, psychosis
(d) renal stones
(e) osteoporosis

11.2.4 Hypocalcemia
Plasma calcium level less than 8mg/dl is called hypocalcemia. Tetany due to
accidental surgical removal of parathyroid glands or by autoimmune disease. In
tetany, neuromuscular irritability is increased. Increased Q-7 internal in ECG is
seen. Main manifestation is carpopedal spasm. Laryngismus and stridor are also
observed. Laryngeal spasm may lead is death. The causes of laryngeal spasm
includes
(a) Deficiency of vitamin D

(b) Deficiency of parathyroid
(c) Increased calcitonin
(d) Deficiency of calcium intake

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Biochemistry

INTEXT QUESTION 11.1
1. The total calcium range in human is ……………..
2. Calcium absorption requires …………….. dependent ATpase.

(a) Ca (b) Mn (c) Mg (d) fe

Notes 3. Factors responsible for increase in calcium absorption include ……………..
4. When plasma Ca2+ level is more than 11mg/dl is called ……………..

(a) Hypercalcemia (b) Anemia (c) Fluorosis (d) Selenosis

11.3 PHOSPHORUS
Total body content of phosphorus is 1 kg. Bone posses 80 % of total phosphorus
and muscle contains 10 % of total phosphorus. Human body requires 500 mg
of phosphorus per day. Milk is the good source of phosphorus and it contains
about 100 mg/dl of phosphrous. Apart from milk, cereals, nuts and meat are
moderate sources of phosprous.

Serum level of phosphate is 3-4 mg/dl for adults and 5-6 mg/dl in children.
Consumption of calcitriol increases phosphate absorption.

11.3.1 Functions of phosphorus
(a) Plays key role in formation of tooth and bone
(b) Production of high energy phosphate compounds such as ATP, CTP, GTP

etc.,
(c) Synthesis of nucleotide co-enzymes such as NAD and NADP
(d) Formation of phosphodiester backbone structure for DNA and RNA

synthesis
Hypophosphatemia is the condition which leads to decrease in absorption of
phosphorus. Further it leads to hypercalcamia, chronic alcoholism and increased
excretion of urinary phosphate. In case of hyperphosphatemia, increase in
absorption of phosphate was noticed. Hyperphosphatemia leads to cell lysis,
hypocalcemia and thyrotoxicosis.

INTEXT QUESTIONS 11.2
1. Bone posses …………….. % of total phosphorus.
2. Serum level of phosphate is …………….. mg/dl for adults.

(a) 4-8 (b) 3-4 (c) 8-9 (d) 1-2
3. …………….. plays key role in formation of tooth and bone

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11.4 MAGNESIUM Biochemistry

Optimal level of Magnesium for human consumption ranges 300-400 mg/day.
The main source of Magnesium includes cereals, beans, leafy vegetables and
fish. The normal serum level of Magnesium is 1.8 to 2.2. mg/dl.

11.4.1 Functions of Magnesium
(a) Irritability of neuromuscular tissues is lowered by Magnesium Notes

(b) Magnesium deficiency leads to decrease in Insulin dependent uptake of
glucose

(c) Magnesium supplementation improves glucose tolerance
Decrease in Magnesium content leads to the condition called as hypomagnesemia.
It causes increase in urinary loss. Causes such as liver cirrhosis, protein calorie
malnutrition and hypo para thyroidism leads to hypomagnesemia. Increase in the
level of Magnesium is called as hypermagnesemia. The main causes of
hypermagnesemia includes renal failure, hyper para thyroidism, rickets, oxalate
poisoning and multiple myeloma.

INTEXT QUESTIONS 11.3
1. Optimal level of ………………. for human consumption ranges 300-400 mg/

day.
2. Irritability of neuromuscular tissues is lowered by ……………….
3. Magnesium supplementation improves ………………. tolerance

(a) lactose (b) glucose (c) toxin (d) microbial

11.5 IRON
Total body content of iron is 3 to 5 gm out of which 75 % is recorded in blood
and rest of them are recorded from liver, spleen, bone marrow and muscle. The
normal limit for iron consumption is 20 mg/day for adults, 20-30 mg/day for
children and 40 mg/day for pregnant women. The main source of iron is jaggery.
Other source of iron includes leafy vegetables and meat etc., Milk is considered
as a poor source of iron.

11.5.1 Factors influencing absorption of iron
Iron is absorbed by upper part of duodenum and is affected by various factors
(a) Only reduced form of iron (ferrous) is absorbed and ferric form are not

absorbed

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Biochemistry (b) Ascorbic acid (Vitamin C) increases the absorption of iron
(c) The interfering substances such as phytic acid and oxalic acid decreases

absorption of iron

11.5.2 Regulation of absorption of Iron
Absorption of iron is regulated by three main mechanisms, which includes

Notes (a) Mucosal Regulation

(b) Storer regulation
(c) Erythropoietic regulation
In mucosal regulation absorption of iron requires DM-1 and ferroportin. Both
the proteins are down regulated by hepcidin secreted by liver. The above
regulation occurs when the body irons reserves are adequate. When the body iron
content gets felled, storer regulation takes place. In storer regulation the mucosal
is signaled for increase in iron absorption. The erythropoietic regulation occurs
in response to anemia. Here the erythroid cells will signal the mucosa to increase
the iron absorption.

11.5.3 Iron transport in blood
The transport form of iron in blood is transferin. Transferin are glycoprotein
secreted by liver. In blood, the ceruloplasmin is the ferroxidase which oxidizes
ferrous to ferric state.

Apo-Transferin + 2Fe2+ ⎯⎯→ Transferin combined with 2Fe3+

Storage form of iron is ferritin. Almost no iron is excreted through urine. Feces
contains iron as well as iron trapped in the intestine cells.

11.5.4 Anemia
Anemia is the most common nutritional deficiency disease. The microscopic
appearance of anemia is characterized by microcytic hypochromic anemia. Iron
toxicity or excess of iron is called as hemosiderosis. Iron toxicity occurs due to
repeated blood transfusion. The abnormal gene responsible for hemosiderosis
is located on the short arm of chromosome No.6. The main causes of iron
deficiency or anemia are

(a) Nutritional deficiency of iron
(b) Lack of iron absorption
(c) Hook worm infection
(d) Repeated pregnancy

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(e) Chronic blood loss Biochemistry

(f) Nephrosis
(g) Lead poisoning

INTEXT QUESTION 11.4
Notes

1. Match the following
Adults 20 – 30 mg/day
Children 40 mg/day
Pregnant women 20 mg/day

2. ……………… is the most common nutritional deficiency disease
3. The transport form of iron in blood is ………………

11.6 COPPER
Total human body contains about 100 mg of copper and are encountered in
muscle, liver, bone marrow, brain, kidney, heart and in hairs. Enzymes such as
cytochrome oxidase, tyrosinase, lysyl oxidase, allanine synthase, monoamine
oxidase, superoxide dismutase and phenol oxidase contains copper. The normal
copper limit for human are 1.5 to 3 mg/day. The main sources of copper are
cereals, meat, liver, nuts and green leafy vegetables. From the total dietary
copper only 10% are absorbed. Copper are mainly excreated through bile. The
normal serum level of copper is 25 to 50 mg/dl.

11.6.1 Functions of copper
(a) Copper is necessary for iron absorption and incorporation of iron into

hemoglobin.
(b) It is very essential for tyrosinase activity
(c) It is the co-factor for vitamin C requiring hydroxylation
(d) Copper increases the level of high density lipo protein and protects the

heart

11.6.2 Abnormal metabolism of copper
The abnormal metabolism of copper leads to Wilson’s disease and Menke’s
kidney hair syndrome.

(a) Wilson’s disease
In case of Wilson’s disease ceruloplasmin level in blood is drastically reduced.
The incidence of Wilson’s disease is noticed for 1 in 50,000 populations. The

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Biochemistry defect in a gene encoding copper binding ATPase of liver cells leads to Wilson’s
disease. Wilson’s disease leads to

(i) Accumulation of copper in liver leads to hepatocellular degeneration and
cirrhosis

(ii) Deposition of copper in brain basal ganglia leads to leticular degeneration
(iii) Copper deposits as green pigmented ring around cornea and the condition

Notes is called as Kayser-Kleischer ring
Over accumulation of copper can be treated by consumption of diet containg low
copper and injection of D-penicillamine, which excretes copper through urine.

(b) Menke’s kidney hair syndrome
It is X-linked defect. In this condition copper is absorbed by GI tract, but cannot
be transported to blood. The defect in transport of copper to blood is due to
absence of an intracellular copper binding ATPase, which is due to mutation in
gene encoding them.

INTEXT QUESTIONS 11.5
1. Total human body conatins about …………….. mg of copper

(a) 100 (b) 200 (c) 300 (d) 400
2. Menke’s kidney hair syndrome is …………….. linked defect.
3. Deposition of copper in …………….. leads to leticular degeneration

11.7 ZINC
The daily requirement of Zinc for human consumption ranges 10mg /day. The
major sources of Zinc includes grains, beans, nuts cheese, meat and shellfish.
The normal serum level of Zinc in human is 100mg/day. In the human total body
the content of Zinc is 2gm, out of which 60 % is encountered in skeletal muscle
and 30% in bones highest concentration is seen in hippocampus area of brain
and prostatic secretion.

More than 300 enzymes in human body are zinc-dependent; some of them are
carboxypeptidase, carbonic anhydrase, alkaline phosphatase, lactate
dehydrogenase, alcohol dehydragenase. The enzyme RNA polymerase, which
is required for transcription, contains zinc and it is essential for protein bio
synthesis.

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Deficiency in Zinc leads to poor wound healing, lesions of skin impaired Biochemistry

spermatogenesis, hyperkeratosis, dermatitis and alopecia. Consumption of more
than 1000 mg /day leads to zinc toxicity. Zinc toxicity leads to gastric ulcer,
pancreatitis, anemia, nausea and vomiting.

INTEXT QUESTIONS 11.6 Notes

1. …………….. and …………….. are major source of Zinc

2. …………….. number of enzymes are zinc dependent

(a) 100 (b) 300 (c) 500 (d) 50

3. The normal serum level of Zinc in human is …………….. mg/day

11.8 FLUORIDE
Fluoride is well known for their protective effect on caries. The safe limit of
fluorine is about 1PPM in water. But excess of fluoride causes Flourosis.
Flourosis is more dangerous than caries. When Fluoride content is more than
2 PPM, it will cause chronic intestinal upset, gastroenteritis, loss of weight,
osteosclerosis, stratification and discoloration of teeth. In India Flourosis is
widespread in Punjab, Rajasthan, Delhi and Tamilnadu. Fluoride rich source
includes sea fish, cheese, tea and jowar.

Flourosis could be prevented by providing and consumption of fluoride free
water, Further supplementation of vitamin c and usage of toothpaste containing
regulated level of Fluoride could prevent Fluorosis.

INTEXT QUESTIONS 11.7
1. ……………… is well known for caries protection.

(a) calcium (b) fluoride (c) iron (d) Magnesium

2. Fluoride rich source includes ………………

11.9 SELENIUM
The normal limit of Selenium for human consumption is 50-100 mg/day and the
normal serum level is 50-100 mg/day. Selenium dependent enzymes include
glutathione Peroxidase and 5-de-iodinase. Selenium concentration in testis is the

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Biochemistry highest in adult. It is very necessary for normal development and maturation
of sperm.

Selenium toxicity could be termed as selenosis. The toxicity symptoms include
hair loss, falling of nails, diarrhea, weight loss and garlicky odor in breath.

Notes
INTEXT QUESTIONS 11.8

1. The normal limit of Selenium for human consumption is …………… mg/day

2. Glutathione peroxides is a ……………… dependent enzyme

11.10 MANGANESE
The normal limit of Manganese for human is 5mg/day. The major source of
Manganese are nuts. In metabolism, its absorption is inhibited by iron. In blood,
it binds with transmanganin and excreted through bile.

INTEXT QUESTIONS 11.9
1. The major source of Manganese is ………………

2. Manganese are excreted through ………………

WHAT HAVE YOU LEARNT
In this lesson you have learnt about the importance and types of clinically
significant mineral elements.
Mineral elements are solid crystalline, chemical elements that cannot be
decomposed and synthesized by ordinary chemical reactions.

They are present in both plants and animals to execute specific functions
and the amount to be required is largely determined by certain inherent
factors.
Minerals although nutritionally required in smaller amounts are essential
for maintenance and production purposes. However the major and trace
minerals are needed by the body in large and small amount respectively.
Generally, deficiencies of most minerals are shown by a reduced appetite
and production, slow growth and occasionally death.

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Biochemistry

TERMINAL QUESTIONS
1. Write a short note on minerals?
2. What are the elements of major and minor minerals?

3. Write a note on calcium and its finctions?
4. What are the functions of phosphorous? Notes

5. Narrate the importance of iron?

ANSWERS TO INTEXT QUESTIONS

11.1
1. 1 to 1.5 kg
2. Ca
3. Vitamin D
4. Hypercalcemia

11.2
1. 80 %
2. 3-4
3. Phosphorus

11.3
1. 300 to 400
2. Magnesium

3. Glucose

11.4
1. Adults 20 mg/day

Children 20 – 30 mg/day
Pregnant women 40 mg/day

2. Anemia

3. Transferin

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Biochemistry 11.5
1. 100
2. X-linked
3. Brain basal ganglia

11.6
Notes

1. Beans and nuts
2. 300
3. 10

11.7
1. Fluoride

2. Fish

11.8
1. 50-100
2. Selenium

11.9
1. Nuts
2. Bile

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