Colloid

Lecture- 'Colloid'

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Prospects of NSTU (Noakhali Science & Technology University)

Education is the backbone of a nation. Educational institutes are called the nation building workshop. University is the highest stage of education. Number of university is there in our country. Noakhali Science & Technology University (NSTU) is one of them and one of the best universities by virtue of its subjects. The site of the university is in fact a pollution free area of Noakhali. Natural beauty around the university is appreciable in comparison with other universities. The atmosphere of the university campus is very much convenient and favorable for study.

The present civilization is the gift of modern science. NSTU is actually belongs to five subjects of pure science which may contribute to the country and nation as well as the whole world. The subjects are Pharmacy, Computer Science & Telecommunication Engineering (CSTE), Applied Chemistry & Chemical Technology (ACCT), Microbiology and Fisheries & Marine Science (FIMS). The teachers are well educated having good art of presentation. They are also very much amicable and have love and affection for the students. The curry column of the university is high standard. Different occasions are celebrated with a great festivity. Teachers and students of this university are very united.

NSTU is always ready to cope up with the new challenges of any scientific revolution. Very soon the university is going to establish a garden of medicinal plants through Pharmacy department. This will contribute the country through invention of new important medicines. Pharmaceuticals of our country play a vital role in the development of our economy. Medicine producing sector is in the second position to earn foreign exchange. So, obviously students of Pharmacy department of NSTU shall produce their best effort to bring financial stability of the country manifold. They will also contribute to build human health.

Computer software has changed our life style; it has made our life sharp and comfortable. Different tasks has become easier, it is being used in different government and non-government organizations & testing unit. Teaching program is also being done with the help of computer. To run the aircraft computer is being used. To diagnoses serious and critical   diseases computer is being used at random. Students of CSTE department of NSTU will be able to provide best effort in every spares of life with the best utilization of computer science. Telecommunication has made the world smaller to us. Rapid development of telecommunication has made our life easier. Every moment we can have news of different persons from far away when we desire. Giving proper service in this sector student of NSTU will play a vital role in the communication world.

Applied Chemistry & Chemical Technology (ACCT) is one of the best subjects of this university. Without application of Chemistry we can not imagine our life even for a day. Chemical Engineer/Technologist plays an important role in different industries. Their work-circumference is in the chemical industry, Cosmetic industry, Glass industry, Steel industry, Ceramic industry, Textile industry, Fertilizer industry, Atomic energy, Paper Mills, Hardboard Mills, Oil refinery etc. No industry can run without chemist. In a word, no industry can run without any chemist. So, we can say without any doubt that the student of ACCT department of NSTU will put their best effort and contribute the country many ways. . Very soon a research centre is going to be established in the university for different research jobs, there will have two special research projects i.e., to produce cotton/yarn from jute fiber and oil from coal.      

Fisheries & Marine Science (FIMS) is one of the four subjects of NSTU.                   Population of this country is increasing very rapidly. But, the land is decreasing gradually because of over population. Accordingly demand for the food and shelter are increasing. To meet the requirement of nutrition, fisheries department can contribute directly. High quality of fish production is possible through modern pisciculture. They can develop the fish production with the application Ichthyology. Marine science is an important subject. Student of this department gather knowledge about marine technology. It has demanded in our country as we have huge sea area. It is also demanded by many other foreign countries. The student of this group may have opportunity to work in home & abroad and can contribute the country both ways.

Microbiology is a newly opened department at NSTU from 2009-10 session.

Besides this there is English department with an ultramodern language laboratory in NSTU. It increases skill ness in English which is essential for higher study. People of this area may be influenced and encouraged to learn English by this department. There is Basic Engineering department by which students of all departments are taught about Electrical Engineering, Mechanical Engineering and Civil Engineering.

There are two play grounds in the university campus; teachers and students play football, cricket, badminton & volleyball, which help the students to be courageous and intelligent in all sectors of their life. There is a Debate Forum, indoor games facilities. Different cultural functions like- Friendship day, Valentine’s Day, 21^st February, 26^th March and 16^th December, the national days are celebrated with enthusiastic way. These are arranged by the students which help to grow creativity of the students.

   

University is the highest stage of education. It should be located at an isolated but well- communicated area. NSTU is located in such a place, the rail way station is not so far away. Very soon the rail way will be extended up to the university. Teachers of this university are very careful about safety and security of the students. Every year number of meritorious students from different areas of the country get admitted in this university. In near future obviously NSTU will take part in economical progress besides nation building. To be student of such a university every one should be very happy and proud of it.    

Electochemistry- Short Note

Electrolysis

            The phenomenin of decomposition of an electrolyte by passing electric current through its solution is termed electrolysis (lyo= breaking).

Mechanism of electrolysis

            The cations migrate to the cathode and form a neutral atom by accepting electrons from it. The anions migrate to the anode and yield a neutral particle by transfer of electrons to it. As a result of the loss of electrons by anions and gain of electrons by cations at their respective electrodes chemical reactions takes place.

            For example, in solution, HCl is ionized,

                                    HCl = H⁺ + Cl^-

At anode:       Cl^- = Cl + e^-

At cathode:    H⁺ + e^- = H

Electrical units

Coulomb

            A coulomb (unit quantity of electricity) is the amount of electricity which will deposit 0.001118g of silver from a 15% solution of silver nitrate in a coulometer.

Ampere

            An ampere (unit rate of flow of electricity) is that current which will deposit 0.001118g of silver in one second.

Ampere = current of 1C/sec.

Ohm

            An ohm (unit of electrical resistance) is the resistance offered at 0^oC to current by a column of mercury 106.3 cm long of about 1 sq mm cross-sectional area and weighing 14.4521grams.

Volt

            A volt (unit of electromotive force) is the difference in electrical potential required to send a current of one ampere through a resistance of one ohm.

Faraday’s 1^st law

The amount of a given product liberated at an electrode during electrolysis is directly proportional to the quantity of electricity which passes through the electrolyte solution.

If w is the mass of substance (in gram) deposited on electrode by passing Q coulombs of electricity then,

            w ∞ Q

We know,        Q = It; I= current in ampere, and t= time in second

Therefore,        w ∞ It

            Or,       w= ZIt; Z= constant known as the electrochemical equivalent

Electrochemical equivalent

            From the 1^st law, we get, w= ZIt;      

Now if I=1amp, t= 1sec, then, w= Z

            Thus, the electrochemical equivalent is the amount of a substance deposited by 1 ampere current passing for 1 second (i.e., 1 coulomb).

Faraday (the electrical unit)

            It has been found experimentally that the quantity of electricity required to liberate one gram-equivalent of a substance is 96,500 coulombs. This quantity of electricity is known as Faraday and is denoted by F.

How can we calculate the charge of an electron by Faraday’s 1^st law?

The quantity of electricity needed to deposit 1 mole of the substance is given by the expression, Quantity of electricity = n X F;      n= valency of its ion

Let, number of ions in 1 mole ion = N

Again, if the value charge of every ion of 1 valency becomes equal with the charge of an electron ‘e’ then, the charge conducted by N ions= Ne.

 So, Ne= n X F coulomb

            =F coulomb; (for 1 valency radical n=1)

Or, e    = F/N C

            =96500/ (6.023X10²³) C

            =1.6 X 10^-19 C

1 Faraday= 96500 C= 1 mole electrons

Application/ importance of 1^st law

            With the help of the first law of electrolysis we are able to calculate:

1.      the value of electrochemical equivalents of different substances; and

2.      the masses of different substances produced by passing a known quantity of electricity through their solutions

Faraday’s 2^nd law

            When the same quantity of electricity passes through solutions of different electrolytes, the amounts of the substances liberated at the electrodes are directly proportional to their chemical equivalents.

Thus, w ∞ E;  w= mass of deposited substance

                        E= chemical equivalent

Chemical equivalent

            The chemical equivalent is the amount of a substance (in gram) deposited at an electrode by 1.0F current passing through the electrolyte solution. It is denoted by E.

Application/ importance of 2^nd law

            The 2^nd law of electrolysis helps to calculate:

1.      the equivalent weights of metals

2.      the unit of electric charge

3.      the Avogadro’s number

Electrolyte

            Electrolytes are electrovalent substances that form ions in solution which conduct an electric current.

            Electrolytes may be divided into two classes:

1.      strong electrolytes

2.      weak electrolytes

Strong electrolytes

            A strong electrolyte is a substance that gives a solution in which almost all the molecules are ionized.

Example- HCl, H₂SO₄, HNO₃, HClO₄, HBr, HI; NaOH, KOH, Ca(OH)₂, Mg(OH)₂; NaCl, KCl etc.

Weak electrolytes

            A strong electrolyte is a substance that gives a solution in which only a small portion of the solute molecules are ionized.

Example- acetic acid, oxalic acid, sulphurous acid (H₂SO₃); alkyl amines; mercury (ll) chloride, lead (ll) chloride.

Conductance

            The power of electrolytes to conduct electric currents is known as conductivity or conductance.

Like metallic conductors, electrolytes obey Ohm’s law. According to this law, the current I flowing through a metallic conductor is given by the relation,

            I= E/R;           E= potential difference at two ends

                                    R= resistance

Again we know that,  R∞ l/A; l= length, and A= cross-sectional area

                        Or,      R = ρ X l/A; ρ = constant of proportionality and is called resistivity or specific resistance.

Specific resistance/ conductance

            We know, ρ = R X A/l

If l= 1 cm and A= 1 sq cm, then ρ= R

Thus, specific resistance of a conductor is the resistance in ohms which one centimeter cube of it offers to the passage of electricity.

            The reciprocal of specific resistance is termed as specific conductance or specific conductivity. It is the conductance of one cm cube of a solⁿ of an electrolyte. It is denoted by κ.

            κ = 1/ρ

Its unit is ohm^-1cm^-1

Equivalent conductance

            It is defined as the conductance of an electrolyte obtained by dissolving one gram-equivalent of it in V cc (the volume of a solution) of water. It is denoted by Λ. Its unit is ohm^-1cm²eqvt^-1.

Molar conductance

            It is the ratio of the conductivity of an electrolytic solution to the concentration of electrolyte in moles per unit volume. It is denoted by µ. Mathematically,

                                                                                    µ = κ X V

Its unit is ohm^-1cm²mol^-1.

Structure & Functions of liver

Liver

            It is a solid organ of dark reddish-brown color and the largest gland in the body.

            In the average adult, the liver weighs about 3 lb. It is situated high in the abdomen and below diaphragm. It has two lobes, in which right lobe is larger containing gallbladder. It is composed of (different parts)-

q  Hepatocytes – major functional cells of liver

n  It has wide variety of metabolic, secretory, and endocrine functions – secrete bile (excretory product and digestive secretion)

q  Bile canaliculi – ducts between hepatocytes that collect bile

n  It exits livers as common hepatic duct, joins cystic duct from gallbladder to form common bile duct.

q  Hepatic sinusoids – highly permeable blood capillaries receiving oxygenated blood from hepatic artery and deoxygenated nutrient-rich blood from hepatic portal vein

q  SPACE OF DISSE

      It is the perisinusoidal space between basal surfaces of the endothelial cells and the surfaces of the hepatocytes.

Why are liver capillaries called sinusoids?

            These vessels are unusual in that their lining cells contain “sieve plates” which allow proteins to pass through into the Space of Disse and there contact the underlying hepatocytes.  Because of this they are termed sinusoids.

Three different ways to organize units

1.      Hepatic acinus – preferred method

n  Hepatocytes arranged in 3 zones around short axis with no sharp boundaries

2.      Portal

3.      Classical- basic functional unit of liver    

Portions of liver

1.      EXOCRINE PORTION

                  It synthesizes and secretes bile via a system of ducts that is essential for digestion in the intestine.

2.      ENDOCRINE PORTION

                  It synthesizes and secretes numerous plasma proteins into the bloodstream:                                         (albumin, fibrinogen, prothrombin, lipoproteins, etc).

Blood Supply to the Liver

            The liver has a dual blood supply.  Only 20-25% of the blood derives from the hepatic artery, the remainder comes from the portal veins which drain the stomach and all the intestines except the rectum.  The liver hence can remove damaging materials before they reach the systemic circulation. Blood leaves the liver via the hepatic veins which join with the ascending vena cava.

Circulatory Zones in the Liver

n  As blood flows from the portal tract to the hepatic venules it gradually loses oxygen.  Although the hepatocytes in the well oxygenated “periportal zone” look similar to hepatocytes around hepatic veins (the centrilobular zone) their enzymology is different.  Cells in the intermediate (midzonal) area are - intermediate

n  Synthesis of blood proteins and gluconeogenesis occur principally in the periportal zone.

Hepatic blood flow

n  Hepatic artery carrying oxygenated blood

n  Hepatic portal vein carrying deoxygenated blood with newly absorbed nutrients and possibly drugs, microbes or toxins from GI tract

Functions of liver

           

Carbohydrate Metabolism

n  Turn proteins into glucose

n  Turn triglycerides into glucose

n  Turn excess glucose into glycogen & store in the liver

n  Turn glycogen back into glucose as needed

           

Protein Metabolism

n  Deamination = removes NH₂ (amine group) from amino acids

n  Converts resulting toxic ammonia (NH₃) into urea for excretion by the kidney

n  Synthesizes plasma proteins utilized in the clotting mechanism and immune system

n  Convert one amino acid into another

           

Lipid Metabolism

n  Synthesize cholesterol

n  Synthesize lipoproteins----HDL and LDL (used to transport fatty acids in bloodstream)

n  Stores some fat

n  Breaks down some fatty acids

           

Other functins

n  Detoxifies the blood by removing or altering drugs & hormones (thyroid & estrogen)

n  Releases bile salts help digestion by emulsification

n  Stores fat soluble vitamins-----A, B₁₂, D, E, K

n  Stores iron and copper

n  Phagocytizes worn out blood cells & bacteria

n  Activates vitamin D (the skin can also do this with 1 hr of sunlight a week)

Gallbladder

            It is defined as the pear-shaped reservoir for the bile.

Layers of gallbladder

         It has three layers.

             1) MUCOSA

                        -lined with tall columnar epithelium and underlying basal lamina & lamina propria

                        - mucosa highly folded and irregular

                        - no muscularis mucosa or submucosa

              2) MUSCULARIS EXTERNA

                        - layers of smooth muscle with irregular orientation

              3) ADVENTITIA or SEROSA

Bile Production

          Bile is made up of the bile salts, bile pigments, and other substances dissolved in an alkaline electrolyte solution that resembles pancreatic juice. It is yellowish green in color and having pH 7.6 to 8.6.

      One quart of bile/day is secreted by the liver. [1 quart = 1.14L (British)

                                                                                             = 0.94L (USA)]

Flow of Bile

n  Bile capillaries

n  Hepatic ducts connect to form common hepatic duct

n  Cystic duct from gallbladder & common hepatic duct join to form common bile duct

n  Common bile duct & pancreatic duct empty into duodenum

Role and composition of bile

q  Hepatocytes secrete 800-1000mL of bile daily

q  It contains mostly water, bile salts, cholesterol, lecithin, bile pigments and several ions.

·         Partially excretory product/ partially digestive secretion

·         Bilirubin – principal bile pigment

o   Derived from heme of recycled RBCs

o   Breakdown product stercobilin gives feces brown color

q  Bile salts play role in emulsification

o   Also aid in absorption of lipids following digestion

Composition of liver and gall bladder bile:

            Constituents                                      Liver Bile                   Gall Bladder Bile

      Water                                                  97.5 g/dl                      92 g/dl

      Bile Salts                                             1.1 g/dl                        6 g/dl

      Bilirubin                                              0.04 g/dl                      0.3 g/dl

      Cholesterol                                          0.1 g/dl                        0.3 to 0.9 g/dl

      Fatty acid                                            0.12 g/dl                      0.3 to 1.2 g/dl

           

      Lecithin                                               0.04 g/dl                      0.3 g/dl

     

      Na⁺                                                      145 mcg/lit                  130 mcg/lit

      K⁺                                                        5 mcg/lit                      12 mcg/lit

      Ca⁺                                                      5 mcg/lit                      23 mcg/lit

      Cl^-                                                          100 mcg/lit                 25 mcg/lit

      HCO₃^-                                                  28 mcg/lit                     10 mcg/lit                  

Function of Bile

          1. Digestive function

                        Bile helps in the digestion of fat and to a lesser extent of proteins and carbohydrate.

            2. Absorptive function

                        Bile helps in the absorption of fat and other substances like fat soluble vitamins, iron, Ca⁺⁺ etc.

            3. Laxative function

                        Bile salts increases peristalsis and thereby help in defecation.

            4. Excretory function

                        Certain substance are excreted through bile

a)       Heavy metals – Cu, Zn, Hg etc

b)      Certain drugs

c)      Bile pigments

d)     Cholesterols

e)      Toxin, Bacteria

f)       Acid-Base balance: Mucin of bile acts as buffer and help in acid-base balance

BILE ACIDS

§  Cholic acid

§  Deoxy cholic acid

§  Cheno-deoxy cholic acid

§  Lethocholic acid

§  Enolic acid

Bile Salts

    -Sodium tauro-cholate

    -Potassium tauro-cholate

    -Sodium glycholate

    -Potassium glycholate

Functions of bile salts

    -Bile salts help in the digestion of fat

    -Bile salts help in the absorption of fatty acids, monoglycerides, cholesterol and other lipids.

Gallbladder Diseases

        Cholelithiasis & Cholecystitis

                1.  Cholecystitis = inflammation of GB

                2.  Cholelithiasis = Stone(s) in GB

                                               

Cholelithiasis

n  GB shows likely sites of stone formation/deposition.

Histology of the Liver

n  Hepatocytes arranged in lobules

n  Sinusoids in between hepatocytes are blood-filled spaces

n  Kupffer cells are fixed star shaped macrophages which live within the sinusoids and throw processes across the vessel.  Their job is to remove particulate materials picked up in the intestine and worn out red blood cells.  They are also very heavily involved in message passing

 References

1.                  Review of medical Physiology, Guyton, 22^nd edition, W. B. Sander’s Company, Philadelphia

2.                  Dictionary of Pharmacy, Md Ali, Tara Publishers, Delhi

3.                  Anatomy & Physiology, F. Evans, 2^nd edition, Prentice Hall Inc., New Jersey

Endocrine System

Endocrinology

ü  Endo = Internal , Crions = secretion

ü  Branches of medical science which deals with the study of different endocrine glands of the body, are referred to as endocrinology.

 

What is gland?

Gland is an organ that consists of cells that secrete materials into other regions of the body.

Types of glands:

There are two types of glands. Those are-

1.   Endocrine

2.   Exocrine

 

Exocrine Glands

These glands typically secrete material into ducts that lead to the body surface or to one of the cavities that is continuous with the body surface, i.e., digestive, reproductive, respiratory tract.

•          Exo = outside and crine = secrete.

 

Endocrine Glands

•          Endo = within.

The glands those do not secrete material into ducts and secrete chemical signals called hormones into the bloodstream where they travel through the body and affect other cells, are known as endocrine glands.

Examples

–        Thyroid, thymus, testes, ovaries, pituitary, pineal, adrenal, etc.

 

Exocrine	Endocrine
Secrete nonhormonal chemicals into ducts	Ductless glands that are located throughout the body
transports the chemicals to a specific location inside and outside the body	secretes hormones into the bloodstream through the fluid that surrounds their cells
Example- Sweat Glands, Salivary Glands, and other Digestive Glands	Example- Thyroid, thymus, testes, ovaries, pituitary, pineal, adrenal, etc

 

Importance of endocrine system

1.   Transmit information from one place to another by the hormone

2.   Maintains the internal environment of the body

3.   Regulate the slow & gradual process of the body function such as growth.

Hormone

A hormone is a chemical substance secreted by a cell or group of cells into the blood for transport to a distant target, where it exerts its effect at very low concentrations.

HORMONE Vs ENZYME

Hormone	Enzyme
Generally protein & steroid	Always protein
Secreted by endocrine glands	By tissue or cell
Acts locally or distally	Generally acts locally
Generally act by producing 3-5 cAMP or specific protein	Act upon biochemical reactions
Named according to the nature, source, & function	According to the chemical change
Specific receptor is required for action	Not required
It is a chemical substance that is secreted into the internal body fluid by one cell or a group of cells, exerting physiological control effect on other body cells.	It is an organic catalyst produced by the living cells.
It does not act as a catalyst	It acts as a catalyst

 

Classification of endocrine glands

1.   Hypothalamus (neuroendocrine gland)

2.   Pituitary glands( master gland)

a.    Anterior Pituitary glands

b.   Posterior Pituitary glands

3.   Thyroid gland

4.   Parathyroid gland

5.   Adrenal gland

6.   Pancrease

7.   Testes & Ovary

8.   Placenta

 

Types of hormones

I.   According to chemical nature

1.   Peptide (at least 3 amino acids)

2.   Steroid

3.   Derivatives of amino acid tyrosine

II.  According to action

1.   General Hormone

2.   Local Hormone

3.   Trophic Hormone

 

Peptide Hormones

1.   water soluble

2.   stored in vesicles

3.   fast acting

4.   short half-life

5.   e.g.-Hormones of anterior pituitary &  pancreas ,ADH, oxytocin

 

 

Steroid Hormones

1.   made from cholesterol

2.   lipophilic

3.   specific protein carrier molecules

4.   slow acting

5.   e.g.- Sex hormones,  Adrenocortical hormone

 

Derivatives of amino acid tyrosine

1.   derivatives of single amino acid residues

2.   primarily TYROSIN

3.   can behave either like peptides or steroids

 

Characteristics

1. lipophilic
2. carrier molecules required
3. surface and intracellular receptors
4. fast and slow acting
5. e.g. Thyroid hormones, Adrenal medullary hormones

 

Mechanisms of Hormones Action

Hormones generally act in three different ways

  1. By Activating the genes of the cell:    steroid hormone generally acts in this way.

  2.  By forming cyclic AMP (cAMP):  protein hormone generally act in this way.

  3. Direct action e.g. growth hormone, insulin etc act directly by changing the permeability of cell membrane.

By forming cyclic AMP (cAMP)

Protein hormones at first binds with receptors at the surface of the cell membrane. This hormone receptor binding stimulate enzyme adenylcyclase This enzyme then converts cytoplasmic ATP into cyclic adenine monophosphate (cAMP).The cAMP then activates a cascade of enzyme action. That is it activates a second enzyme which activates a third and so forth. In this way hormone acts on the cell.

Cell may response in following ways

a.    Activates enzyme

b.    Alter cell permeability

c.    Cause muscle contraction or relaxation

d.   cause protein synthesis

e.    cause secretion

 

Hormones act by cAMP system

1. Adrenocorticotropin

2. Thyroid stimulating hormone

3. Luteinizing hormone

4. Follicle stimulating hormone

5. Vasopressin

Regulation of Hormone Secretion

Most hormones are controlled by a FEEDBACK mechanism

Types of feedback mechanism:

There are two types of feedback control:

1.   Negative Feedback

2.   Positive Feedback

Negative Feedback

1. Most hormone systems use negative feedback in which release of an initial hormone stimulates release    or production of other hormones or substances that subsequently inhibits further release of the initial hormone.
2. The hypothalamus, the anterior pituitary, and the other endocrine controlled by the anterior pituitary are all involved in a self-regulating negative feedback mechanism.

 

Positive Feedback

1. in positive feedback, release of an initial hormone stimulates release or production of other hormones or substances, which stimulates further release of the initial hormone.
2. One example of this is the surge of luteinizing hormone (LH) that occurs as a result of the stimulatory effect of estrogen on the anterior pituitary before ovulation.
3. The secreted LH then acts on the ovaries to stimulate additional secretion of estrogen, which in turn causes more secretion of LH.

 

Structure of Pituitary Gland

The pituitary gland ,also called hypophysis, is a small gland –about 1 cm in diameter and 0.5 to 1 g in weight that lies in the sella turcica at the base of the brain and is connected with the hypothalamus by the pituitary stalk.

            The pituitary gland is divided into two parts

a.    Anterior pituitary

b.    Posterior pituitary

 

 

Secretion of different parts of pituitary glands

     1. Posterior Pituitary

                                         i.    Antidiuretic hormone

                                        ii.    Oxytocin

     2. Anterior Pituitary

                                         i.    Growth Hormone (GH)

                                        ii.    Prolactin (PL)

                                       iii.    Follicle-stimulating Hormone (FSH)

                                      iv.    Luteinizing Hormone (LH)

                                        v.    Thyroid-stimulating hormone (TSH)

                                      vi.    Adrenocorticotropic hormone (ACTH)

     3. Middle Pituitary

                                     i.        Melanocyte stimulating hormone (MSH)

 

Anterior pituitary

          Functions of the secreted six major hormones are given below.

1. Growth Hormone (GH)

                     i.        regulates body growth

                    ii.        increases protein synthesis, fat use, CHO storage

                   iii.        bone growth

2.   Prolactin (PL)

                       i.        development of mammary glands during pregnancy

                      ii.         milk production

3.    Follicle-stimulating Hormone (FSH)

                         i.        production of sperm, testosterone

                        ii.        production of ovum,estrogen, progesterone

4.    Luteinizing Hormone (LH)

                         i.         production of sperm, testosterone

                        ii.        production of ovum, estrogen, progesterone

5.    Thyroid-stimulating hormone (TSH)

                       i.        stimulates thyroid gland to produce thyroxine & tri-iodothyronine

6.    Adrenocorticotropic hormone (ACTH)

                     i.        stimulates adrenal gland to secrete adrenocortical hormone

 

Posterior Pituitary

          Functions of the secreted two major hormones are given below.

1.   Antidiuretic Hormone (ADH/vasopressin)

                           i.        Cause the kidney to retain water, thus increasing the water content of the body

                          ii.        High concentration causes constriction of the blood vessel throughout the body and elevates the blood pressure. 

2.     Oxytocin

                               I.        Acts on smooth muscle

a)   milk release from mammary glands

b)   uterine contractions

 

Problems with GH

a)   Too much GH in children leads to gigantism

b)   Too little GH in children leads to dwarfism

c)   Too much GH in adults leads to acromegaly