Transcript for:
Understanding Chemical Levels of Organization

so this section or this chapter is on the chemical levels of organization we will learn the role of chemistry in our lives there are several questions that come to our mind when in our day to day activities for example why is the sodium our cholesterol levels when high or low harmful to the body why when you have diarrhea or you're vomiting it can be detrimental to your body what is anemia what is iron deficiency anemia these are the several several questions that come to our mind and we have to face them in our day-to-day activities for this we need to know the chemical levels of organization so um first let us understand the role of chemistry in the life okay chemistry is a science that deals with structure of matter okay so the question is what is matter matter is defined as something that has mass and has space okay that occupies a space that has mass and occupies some space is known as matter what is mass mass the amount of material in matter is considered to be mass so what is the amount of material in a typical substance is known as mass so matter actually exists in three different forms or three states of matter exists number one solid liquid and gas so all matters are in this form either in solid form liquid or gaseous form so so let's understand now so so all of these the different substances around us okay we are made above different substances which are called elements okay so these elements actually are unique substances that cannot be broken down by ordinary chemical needs so I you emphasize on the world ordinary because eventually we will learn how these different elements can be broken down but my ordinary chemical means these are unique substances that are present around us these are the matter is made up of these elements now atoms these are the building blocks of the elements so atoms make up the elements the atoms each of if there are many many atoms in present these are the smallest stable units of matter is atoms and they are the building blocks of the element air whether it's elephant oranges oceans rocks and people are all composed of atoms in different combinations the unique characteristics of each object living nonliving result from the different types of atoms involved and the ways these atoms combined and interact and these atoms have atomic symbols and we learn that eventually so we have some major elements in our body there are many other elements but I just want to make sure that you understand that there are 91 naturally occurring elements on the art and 24 of which play normal physiological roles in human in this chart as you can see it in here the top of the ladder is oxygen and it occupies 665 percent of human body weight carbon which is denoted by C ha occupies about 19% hydrogen which is denoted by H occupies about 10% so the top 3 you do have to remember oxygen carbon and hydrogen because eventually we will see how important these elements are in our body so atoms these elements are made up of atoms atoms have a general structure they have made up of three sub atomic particles number one protons number two neutrons and number three electrons and we learn each one of them number one is let's understand protons these are positively charged and have mass neutrons have no charge and have mass electrons are negatively charged and have negligible mass or you can say they have a mass of 1 by 2 mm the mass of a proton which is negligible again protons are positively charged and they have mass neutrons have no charge and but they have mass electrons are negatively charged and they have negligible amount of mass so if you look in here in the center in the center are present the protons and the neutrons again protons are positively charged neutrons are neutral and revolving around them is the electrons I want you to understand so the center part which consists of protons and neutrons is called the nucleus and the electrons revolve around the nucleus and this electrons revolving around the nucleus these are these orbits are known as either orbits they can be called orbitals they can be called electronic shells okay so you have to understand these there are deaf names for it so orbits are vitals electronic shells valence shells there's a fourth one valances these are all different names in which these electrons revolve around the nucleus the the structure the entire structure which consists of protons neutrons and electrons time to scale up with different models as to how they are organized number one is called the planetary model which looks like the solar system with the Sun in the center and the planets revolving around it so you can see this is the center part and this is where the electrons are basically the planets which revolve around the Sun as you know days went on it became more clear that these electronic shells are not so discreet they are not so discreet and most likely they are regions around which they revolve so these then came the concept of all vital models so these these shells are these electronic shells we're then consider that it's not one orbit there are many many orbits on which the electrons move and it is more like a cloud than a really straight line in which the electrons would move okay some terms that you need to know one is the atomic number so what is atomic number it is equal to the number of protons that is present in an atom okay so if the atomic number of an atom is 6 means the number of proton is 6 ok so I want you to understand this concept very well is that the number of proton is equal to the number of electrons why because atom is electrically neutral so the number of positive charge has to be equal to the number of negatively charged what is number of positively charged is protons so number of negatively charged is electrons so this has to balance each other so if the atomic number of an atom is 6 the number of proton is 6 number of electron is also 6 okay so that makes it clear always remember again atom is electrically neutral next comes a mass number this is equal to the mass of proton and neutron so basically if we see it if we calculate the mass number it is the mass of the protons and mass of the neutrons then comes isotopes what are isotopes atoms with the same number of protons but have different number of neutrons so here please understand protons are positively charged neutrons are neutral so isotopes have the same charge so number of and protons are the same but the number of neutrons are different so we will learn about the different elements different atoms with an atomic number in the first slide and then we learn about the isotope in the subsequent slide so these are the different kinds of elements number one is shown hydrogen helium and lithium so hydrogen has 1 proton 0 neutrons and 1 electron so as you can see it in here the atomic number of this atom is 1 why because the number of proton is 1 I want to you know really take what I just said before atom is electrically neutral so number of protons is equal to the number of electrons so it is electrically neutral so atomic number is 1 ok helium helium the two protons two neutrons and two electrons so that number is two and you can see the number of protons are true and number of electrons also is true to then comes little lithium has three protons for neutrons and three electrons again so again atomic number is three number of protons three number of electrons is three in here what is shown is that the number of neutrons in each of these cases are different so atoms have can have you know same number of protons and electrons if they have a different number of neutrons they are a different atom or they form a different element eventually okay so here is shown isotopes okay this is the isotopes of hydrogen hydrogen deuterium and tritium you have to remember the four isotopes the number of our atomic number is the same so for example in hydrogen the atomic number is 1 in deuterium atomic number is 1 Christian atomic number is 1 what does that mean it means number of proton is 1 number of electron is 1/4 do tration do deuterium number of proton is 1 number of electron is 1 trishul number of proton is 1 number of electron is 1 but they are isotopes of each other that means the number of neutrons if you see is different among them ok so number of neutrons in case of isotopes are different I'm going back in slide to show you one similar thing in here number of protons neutrons were both different in each of these n men so these are not isotopes of each other but this these elements who have the same atomic number are isotopes of each other now now we need to understand something which is that these atoms have different atomic number and some are more stable than the others okay some have more stability or control on the number of electrons and neutrons than others here specifically we are interested in number of electrons the electrons are arranged in different shells if you remember we just learn how these are called orbits or vitals electronic shells these electronic shells arrangement of these electrons are different in different elements depending upon the number of electrons as has the first electronic shell always holds two electrons the next electronic shell holds eight the third electronic shell holds 18 so 2 8 18 or it can be 2 8 8 so in each of these cases if the octave or the electronic shell has two electrons then the atom is called a knot because it is very stable and it will not go into any chemical bonding if the atom on the other hand has a one electron then it is calm it is very chemically active and it will try to go for bonding so any atom that has its first shell two electrons that consider to be very stable another atom which has a four shell to and the second shell eight is again very chemically you know inert and will not go into bonding and it's known as inert and Men again the third element which is can we - 8 & 8 or 2 8 and 18 they are also very chemically stable and are known as inert elements any other elements which have lower than the complete octave of two eight eighteen or two eight eight are chemically active and will go into what is called bonding okay so if you look in here so the in this case you can see hydrogen has one electron in the outermost shell as such it is very chemically active the other is carbon it has four shinto and the next shell it has four again it is very chemically active oxygen has two and six sodium has two eight and one and in each of these cases you can see that the shells are not completed with the electrons that it can hold as such they go into chemical bonding so the chemical bonding is of three types number one it is in our in our ionic chemical and hydrogen sorry then ionic covalent and hydrogen these are the three different kinds of chemical bonding ionic bonding okay ions are formed in this case okay what does that mean it means that electrons are transferred from one atom to the other in order to go into stability so they are going to form a bond that means they are going to either give a very some electrons to form stability or they are going to take up some electrons in order to gain stability or stability or stable environment what it means is it is trying to achieve the inert compounds configuration which means that it is trying to achieve two electrons in its first shell or it is trying to get to plus eight electrons in the second shell or it is trying to get to 818 or two eight eight on it electronic cell shell so that it forms the configuration of an inert compound or inert gas citizen so two atoms that gain one of our more electron is known as an ions and atoms that lose one or more electrons are known as cations so they form ions anions and cations water and ions that have gained one or more electrons so when they gain one or more electrons it results in a more negative charge cations lose electrons so they give of a negative charge as such they become positively charged so anions are negatively charged cations are positively charged so let's understand how it takes place the ionic bonding ionic bonds form between atoms by transfer of one or more electrons when they transfer electrons when they give away electrons as I said they become positively charged and the atom that receives electron becomes negatively charged the best example is sodium chloride NaCl and a CL has an electronic atomic number of 11 so the distribution of electron is two plus eight plus one okay so you can see it in here two plus eight plus one on the other hand chlorine has atomic number 17 the electronic configuration is for shell 2 second shell eight and third shell seven okay so I want you to understand for sodium that is one extra electron on the third shell and chlorine has seven electrons on the third shell in order to gain stability sodium will try to give away one electron on the other hand chlorine will try to take up an electron in that case this transfer of electron from one to the other or gain of electron from one to the other is known as an ionic bond as a result you can see there is an ionic bond form but there are charges that are formed as a result of it sodium gets a positively charged because it gives away one electron chloride it gains one electron as a result it becomes negatively charged and their forms a bond which is an ionic bond and the compound form is called NaCl which is common salt next comes the covalent bond covalent bond is more like sharing of electron in this case the atoms don't give up electrons atom don't take up electrons they share in order to achieve the inert gas configuration okay share means for example you have $500 and your friend has $500 and you rent a room which is thousand dollars and you share it okay so you're sharing the property amongst yourself okay and this by doing that both are gaining something and that is nothing but covalent bonding in this case atoms are sharing electrons amongst themselves I point here they do not give up electrons they're just sharing their electrons with one another so let's take the example of methane gas which is the formula is ch4 so this is one carbon and four hydrogen's so this is carbon which has an electronic configuration of six which is economic numbers so two atoms in the fourth shell and four atoms in the second shell - in the four shell four in the other shell so carbon which has atomic number six - plus four is electronic configuration so in order to achieve the inert configuration carbon requires four addition additional hydrogen or what it can do it can give up the four electron that is on the outermost shell both are difficult so what it does in order to giving instead of giving up four electrons it shares the electron with four different hydrogen atoms if you remember hydrogen has atomic number one so it has one electron on its electronic shell so each of these four electrons will be sharing the electron with four other hydrogen as a result they form a bond and then forms a compound or a molecule you can say which is called a methane gas ch4 and it's written this way we have several such compounds as we will discuss eventually but I want you to understand this concept that in this case there is no charge form per se okay right now what we are learning is we are not seeing any charge form only there is sharing of electron and that is equal sharing of electrons now this electronic sharing can be of different you know different levels one is it can form a single mode or it can form a double bond or it can form or triple bond so the first is when it is forming a single bond in case of methane one electron from carbon one electron from hydrogen there forming a bond and as such this is a single more covalent bonding that is formed in here in case of oxygen it is little different the first shell is 2 electron the second shell has 6 electron so it requires 2 electrons from the other compound or other atom in this case it shares its electron with another oxygen which also requires 2 electrons as such they form a bond a covalent bond with two of its electrons so now oxygen has two electrons in the first shell and has two six eight six electron of its own and two ill across from the other oxygen so it has eight electrons from the second shell so this is Oh 2 or oxygen gas that is formed the triple bond can be formed exactly the same way nitrogen has two electrons in this first shell has five electrons on the third shell it requires three more electrons so it can share with another nitrogen to form a triple bond and as I said these are not charged because they are having equal equal amount of sharing of electrons now we need to understand what we learned so far is equal sharing of electrons now there can be sharing of electrons but it can be unequal sharing of electrons okay when there is equal sharing of electrons there is no charge formed and it is called a nonpolar molecules okay when there is unequal sharing of electron it is called polar molecules because it develops a slight positive or slight negative charge known as Delta positive or Delta negative okay so we'll learn about that but just remember I will go back to the example that we just gave if we are renting a room 500 given by x person 500 given why person and they share the room that is a non-polar molecule because there is equal sharing of molecules electrons now if X gives $600 and Y gives $400 you still rent the apartment but the amount of money that is given or shared is unequal same thing in here on equal sharing of electron some atoms have more attraction towards electrons and some have less as a result it results in an unequal sharing of electrons so I want to give you an example in which we will come to hydrogen Monday but remember in water h2o what happens is oxygen and hydrogen art forms so the example is in here so we will go back to the polar covalent bond and then I'll come to the hydrogen bond so if you see this is oxygen and this is hydrogen oxygen requires two electrons in order to complete its octave that is 2 plus 6 it has it means additional 2 so as a result it bonds with two hydrogen atoms hydrogen requires one electrons so it will you know bond with oxygen but since oxygen has six electrons on its outermost shell it has more power you can say it has more control on its electrons as a result it develops a delta negative charge and hydrogen develops a delta positive charge so this is a covalent bond but it is a polar covalent bond when there is sharing but the sharing of electrons is unequal this leads us to the next bonding which is known as the hydrogen bonding the hydrogen bonding is a very weak kind of mourning you have to remember that it's a very weak covalent bonding was the strongest kind of bonding hydrogen bonding is a weak attraction between slightly positive hydrogen atom in one molecule and a slightly negative negative oxygen on the other so if you see in here the oxygen molecule has slightly negative charge and the hydrogen molecule has slightly positively charged and these two molecules are they come together to form a bond which is known as the hydrogen bond whoa after as you can see it in here water is the best example so each of these molecules are held together by these hydrogen bond which is present in here hydrogen bond is also present in several proteins and DNA where it is very useful to form coils it forms three-dimensional structure although it's a weak bond but it has many many functions this leads us to the second part of the lecture which is by chemistry you you you you by chemistry so we are going to learn about the compounds with which our body is made up of and they are classified into two parts organic compounds and inorganic compounds organic compounds always contain elements carbon and hydrogen and are generally also accompanied with oxygen so carbon hydrogen and oxygen are the main elements in the Arkana compounds there are other elements also but necessarily carbon hydrogen and oxygen is present in inorganic compounds on the other hand carbon and hydrogen is not present there are exception to the rule of Mars like water which is h2o has hydrogen and oxygen but it is an inorganic compound co2 which has carbon is an inorganic compound but there are exceptions but in general inorganic compounds do not have carbon and have a carbon and hydrogen so we are going to start with inorganic compounds first and then we'll go into the organic compounds so let's understand the different chemicals reaction that take place and then we'll come into line our compounds involving them self sterilize and function by controlling chemical reactions in a chemical reaction new chemical bonds are made they are broken they are remade and so on these changes take place as atoms in the reacting substance called reactants and then they produce what is called a new compound or a different compound which is called the products so as you can see in here in this slide is shown that there are chemical bonds that are formed rearranged or broken and these different chemical compounds arranged in the form of reactants and products so here the example hydrogen two of these hydrogen atoms which are known as reactants they form the hydrogen gas which is a product so so these changes as the atoms are reacting which are known as reactants they are rearranged to form different substances which is the product so here on let's understand what are the different parameters that involve or help or influence the rate of chemical reaction temperature with increase in the temperature usually the chemical reaction always proceeds faster particle size the smaller the particle size the faster usually the chemical reaction is larger molecules require much higher time or require more temperature in order to do the reaction so particle size smaller the size faster is the chemical reaction concentration higher the concentration faster is the chemical reaction catalyst important they are chemical chemicals that increase the rate of reaction without themselves being changed so these catalysts are responsible to increase the rate of reaction enzymes in our body are biological catalysts and they help to increase the rate of reaction in our body now there are several um there are several reactions that take place in our body and these reactions are a combination reactions they can be a composition reaction or many other forms of it but they are in general classified into three parts number one combination reaction or synthesis reaction number two decomposition reaction and number three exchange reaction the first one which is the combination reaction or synthesis reaction is basically in which if there is assembly of smaller molecules together to form a larger molecule for example you can see a and B join together to form a B so an example of it will be in our body our different amino acids they join together to form a protein okay so this is a example of combination reaction with two elements are two substances joined together to form a product next comes the decomposition reaction which breaks a molecule into smaller fragments molecules large molecules are broken down into smaller molecules and this actually is absolutely necessary in order to facilitate for example digestion larger molecules it can be polysaccharides disaccharides are dissolved in water and they are broken into smaller glucose molecule in order to facilitate the reaction so a B which is a large molecule is broken down by a and B now the next is the exchange reaction parts of the reacting molecules are shuffled around to produce new products for example if he reacts with C to form AC plus me for example again glucose in the presence of water is formed co2 and h2o so there is shuffling of the reacting molecules to form the products so these kind of different kind these reactions are continuously going on in your body and they are absolutely necessary in order for you to function properly so the question now arouses arises that there is the recognition that the fluids are the body fluids how are they regulated regulation of the body fluid is done by the pH which is absolutely vital for homelessness so before we even understand pH let's understand little bit brief of the background behind pH well we have learned that hydrogen atom has atomic number one if you remember so it has one electron on its outer shell this makes hydrogen very very easy to go into chemical bonding that is it can easily give up one electron to form hydrogen plus ion or hydrogen ion a hydrogen atom involved in a chemical bond or participating in a chemical reaction can easily lose an electron to become hydrogen ion hydrogen ions are extremely reactive in solution in excessive numbers remember they can break down chemical reaction change the shape of complex molecules and generally disrupt the cell and tissue function as a result the concentration of hydrogen atoms in the body must be highly regulated and there comes the importance of the pH so what is pH pH is the hydrogen ion concentration in body fluids that is pH but mathematically it is a negative log of hydrogen ion concentration the pH of a solution is defined as the negative logarithm of hydrogen ion concentration and is measured in moles per liter it ranges from zero to 50 as you can see this is a pH scale by which we can measure the hydrogen ion concentration the pH scale ranges from zero to fourteen with seven in the middle which is known as neutral with lorring from seven to maybe zero this increases the acidity of the solution with increase in the pH it increases the basicity or alkalinity of the solution okay so let's take a little bit brief moving to understand what acidity and basicity is so whenever in solution hydrogen ions are formed dissociated a solution is dissociated to form hydrogen ion that gives the acidic part of the solution we know that's acidity of an acid usually is a solute that actually dissolves in a solution to produce hydrogen I on the other hand a base is a solution in a solute is a solute which removes hydrogen ion from the solution and usually did it releases Oh H on hydroxyl on so going back this is the neutral pH if you go lower than seven it becomes increasingly more acidic if you go higher than say seven to 14 it becomes basic that is it the hydroxyl ion concentration increases in here this pH helps us to understand the acidity or basicity of the solution or solution in your warrior fluency not solely money in the day to day lives you can see these are the different substances you can measure the the pH of a solution for example the Stillwater has be 87 which is considered to be neutral coffee which has increasing as the acidity which is pH 7 is more acidic than distilled water same is true for lemon juice lemon juice which has a pH of 2 is more acidic than coffee on the other hand if you contain consider household bleach pH pH 12 is definitely has a higher basicity than the store water milk of magnesia and household bleach if you consider these two so household Beach has a higher basicity than milk of magnesia so you understand here we are talking about comparison between these different substances to understand the pH scale of our body so 2 this is in general in our day-to-day lives in the body tube there are several fluids that require this pH regulation or hydrogen ion regulation in order to function better so um so again let's understand one last time a solution with a pH 7 is said to be neutral because it contains equal number of hydrogen and hydroxyl and a solution is called acidic meaning that it contains more hydrogen ions and less hydroxyl ion a solution is considered to be basic on alkaline meaning it has more hydroxyl ID than hydrogen ion so this scale actually helps us to understand the different fluids in our body that have different pages this can be used in our day to day lives in our bodies also this takes us to acids and bases and as we said what are assets and as it is a solute that dissolves in solution and releases hydrogen eye so if you dissolve acid in a solution usually water it will give you hydrogen and thus lowering the pH remember lowering the pH it goes below seven because hydrogen ion atom because a hydrogen atom that loses its electron consists solely of a proton right if you remember as I said hydrogen has one electron and one electron is lost so it just has one proton hydrogen I are often rope referred to as as they are also called as proton donors a strong acid dissolves completely in solution and a reaction occurs eventually which is usually in one direction only usually hydrochloric acid for example with dissolved to form H+ and Cl minus which is a strong acid it ionizes hydrogen hydrochloric acid ionizes to form two ions one is hydrogen ions other is chloride ion since it forms hydrogen ion in solution it is an acid a base is a solute usually which removes hydrogen iron from the solution and thereby acts as a proton acceptor so hydrogen ion is a proton since it removes it from there it is a proton acceptor in solution it usually produces hydroxyl ions so if you see NaOH sodium hydroxide produces two ions sodium ion and hydroxyl ions so this hydroxyl ion usually is produced in case of bases and this hydroxyl ion is able to bind with hydrogen ion to remove hydrogen ion from the solution so bases actually act to release hydroxyl ion and a proton acceptors now the other thing that we need to understand is the acid based concentration which we just learned is the pH of an acidic solution and a basic solution which is acidic solution have higher hydrogen ion concentration alkaline solution have a lower hydrogen ion solution a neutral solution have equal number of hydrogen and hydroxide solution so before we go into this part I just want to give you a little information regarding salts we learned about acids we learned about bases solids is another compound a salt is an ionic compound consisting of any cation accept hydrogen ion and any anion except Hydra hydroxyl ion so basically these are salt are for example NaCl dissociates in sodium and chloride NaCl is a salt okay so this brings us to the next part which is called buffers buffer the compound that stabilizes the pH of a solution by removing or replacing hydrogen ions so they resist any change in the pH in the body fluids by stabilizing the pH of our body by either removing the hydrogen ion or replacing the hydrogen ion for example buffer systems involved in our body a typical buffer system is sodium carbonate acid bicarbonate buffer system as you can see it in here the body's carbonic acid bicarbonate buffer it consists of carbonic acid and sodium bar component in hco3 otherwise known as baking soda buffers and buffers in the body helped to maintain the pH within normal limits so these buffers are present in our body which keeps the pH of the of our bodily fluids under normal conditions for example the human cell requires a pH of 7.4 as you can see it in here and in order to keep that there are several buffers that it just I said the body's carbonic acid bicarbonate buffer system helps in maintaining the balance between them in order to keep heat the page at 7.4 now we are moving on from the inorganic substances that we learned so far into organic substances organic substances are molecules that are present in the living system which are primarily made up of carbon and hydrogen they also have oxygen in them and many have can have sulfur nitrogen iron and other substances but they are rare they are these organic substances are mainly of four different types one is called by carbohydrates lipids proteins and nucleic acids again carbohydrates lipids proteins and nucleic acids we'll go over each one of them as we go along first let's understand a little bit more about the organic compounds so what does the word organic mean any molecule where carbon is bonded with hydrogen is known as organic molecule there are several examples like methane ethanol formaldehyde and glucose these are all organic compounds but many biological molecules are Janique like sugar molecule glucose is also sugar steroids proteins DNA are all part of the organic molecule so organic compounds as we just learned always have carbon Hendra hydrogen and sometimes can have oxygen they are usually covariantly born bonded with each other I want to emphasize here one thing is that these organic compounds are made up of carbon and hydrogen and rest all the other elements in so far known are placed in the inorganic compounds so there is definitely a unique property of carbon that may gives it completely separate a group which is all three compounds that is carbon has a huge ability to form long chains and these long chains with hydrogen or oxygen gives carbon a unique property to make different kinds of compounds and that's kind as the organic compounds forty percent of the body mass are made up of these compounds and there are four classes as we just said these are huge molecules okay these macromolecules are known as polymer except for protein which is not a polymer rest all three are considered to be polymers because they are macromolecules some of the functional groups that are present in the organic compounds is carboxylic group COOH this is carboxylic group and these are these carboxylic groups are present in fatty acids and amino acids amino group may be present which is NH two which is present in protein the building blocks of proteins are your acid and it is present in the amino acids hydroxyl group may be present Oh H it is present in carbohydrates amino acids and fatty acids phosphate groups are rare but present in some nucleic acid have phosphate groups and phospholipids hanck phosphate groups so these are in general these are the groups which are which each of these organic compounds are attached to and they have unique properties that they play in our body so starting with carbohydrates I'm pretty sure all of you know what carbohydrates are and you have carbohydrates every day so let's understand a little bit more about carbohydrates so proteins all sugars structures are made up of carbohydrates so it is a very very important source of energy and is stored in the body cardo and high break these two words carbo and harvest it's made up of carbon and water water in turn is made of hydrogen and oxygen so carbohydrates are made up of carbon hydrogen and oxygen in the ratio of 1 is to 2 is to 1 so they are made in carbon hydrogen and oxygen in the ratio 1 is to 2 is to 1 there are 3 different classes of carbohydrates monosaccharides disaccharides and polysaccharides saccharides this word saccharides means sugar mono means one so if it has one sugar molecule it's known as monosaccharides if it has two is known as disaccharide when it has many it is known as polysaccharides so the main main function of carbohydrate is energy it stores energy in the form of ATP it can store in the form of energy it can store a tip in the form of energy in mass in labor sugar is also the building block of nucleic acid which we will also be studying in this section so some of the major functions of glucose is to provide energy usually it is in the form of glucose which is present in the blood carbohydrates also are are important because this they are they can act they can be present in the proteins as part proteins in our case and they can help in the building and maintaining our body body tissue carbohydrates is a main resource for regulating of north to shore nerve cell because glucose is the only only source of energy that is taken up by the nerve cells no other form of energy can be utilized by the nerve cells carbohydrates also have high fiber content as such they help in the process of constipation they help to in certain diseases to stop certain diseases like cancer heart disease and diabetes so we are going to start with the structure of the carbohydrates it is present carbon hydrogen and oxygen in the ratio of 1 is to 2 is to 1 it is classified into three parts monosaccharides as you can see glucose fructose galactose are all part of monosaccharides deoxyribose and ribose which are the main sugars use in nucleotides or nucleic acids are also monosaccharides disaccharides when two monosaccharides join together by the dehydration process releasing a water it forms a disaccharide sucrose is a combination of glucose and fructose maltose is a combination of two cluepers molecules lactose is a combination of galactose and glucose lactose president Malcolm polysaccharides these are complex carbohydrates okay they are usually 10200 monosaccharides when they join together by the hydration process they form complex carbohydrates starch which is present in plants and cellulose which is also present in several animals these are starch cellulose are present and they are important have dietary you know functions they are important in our body but these are complex carbohydrates and they are hard to digest starch is a glucose in the indian plants and high concentration of glucose in plants or animal cells is toxic so surplus of glucose is converted to convert it to starch for safety so whenever there is excess glucose it can be stored in the form of starch so that it does not it is not toxic to our body glycogen again glucose in in our blood also you if you remember Lukas if is in very high concentration in our blood is taken up by insulin and convert it into glycogen by the liver and stored and stored so that as and when required it can be released and can be used by the body cellulose is also called dietary fiber water soluble found in fruits veggies and it is it's an insoluble fiber is in nuts and grains also so it does help in in the movement of mouth and it is a complex carbohydrates I want to mention here complex carbohydrates is a difficult is difficult to digest so it needs a rigorous process in order to be broken down into smaller glucose molecules so that it can be digested by the body like carbohydrates lipids no more lip comes from was L I POS called fat contain hydrogen carbon hydrogen and oxygen okay the carbon to hydrogen ratio is nearly once T 2 they have less oxygen than carbohydrates in general so lipids are actually lipids or fats you can call them have carbon hydrogen and oxygen with oxygen being less in them okay they are hydrophobic that is they are it's soluble in a water and they are classified into five different classes called fatty acids echinus I'd say closer I'd steroids and phospholipids one of the most important function of lipids are that these are the structural components of the cell walls of the cell okay so phospholipids a makeup it's called phospholipid bilayer because there are two layers of it and they make up the cell wall so it's absolutely necessary that we have lipids in our body you might have heard that facts are not good for your health yes in excessive amounts they are not good for health but they are required in our body they're essential recoil in our body because they are the building blocks of the cell wall so some of the major functions of lipids the second one we just second point we just discussed is they form the membranes along the along the cells that is a cell wall they store energy they are deform hormones and vitamins so lipids are essential for our body so neutral a fact they are called triglycerides as you can see they are try and endless ride so this is a glycerol molecule sorry this is the glycerol molecule where this glycerol molecule has three carbon atoms and and hydroxyl atom attached to each one of them and these hydroxyl atoms then attach you have reactions with three sets of fatty acids and these fatty acids have the carboxylic group as you can see it in here they react together to form what is known as a neutral flat or a triglyceride okay so these are all with three chains of fatty acid form a triglyceride okay I want to mention here if in case of two of these fatty acids or one of these fatty acids are replaced by a phosphate group then it becomes phosphoglycerate okay so when there are three fatty acids its triglyceride when there are two fatty acids it's diglyceride and when one of the facets is replaced by a phosphate group is known as phosphatase right so the triglycerides can be classified actually too saturated and unsaturated fatty acids saturated fatty acids are found in many animal products and are solid at room temperature and they are highly linked with the cardiovascular disease so they are not very healthy form of fatty acids unsaturated fatty acids are liquid at room temperature and are usually plant I have the plant origin so we go into the next part which is this distrust showing you how saturated fatty acids are solid an example of it is beef fat and a peanut oil is an example of unsaturated fatty acid which is liquid there are other fatty it's like for example phospholipids steroids and econo sites if you remember I just mentioned phospholipids are the building blocks of the cell wall what are phospholipids and the structure we learned subsequent slide but remember they are modified things right and they have a phosphate group in them the steroids these are flat molecules with interlocking hydrogen rings and hakuna sites there are twenty carbon fatty acids and they are also found in the cell walls cell membranes and example of them are prostaglandins so phospholipid as I was saying phospholipids have a phosphate group and and have two molecules of fatty chain okay so if you look in here this is the glycerol molecule as you can see this is the glycerol molecule and these are the two fatty chains to which it is attached to and attached with it is a phosphate group here okay so that's the reason is called phospholipid bilayer phospholipids and the phospholipid bilayer is for the cell wall okay so this is this forms a chain like substance so this small black is the backbone of it and there are two fatty chains these are hydrophobic this hydrophobic the word phobic means phobia means fear hydrophobic means they are fearful water which is that is they are not soluble in water and the phosphate part of it is polar head it is hydrophilic philic means love hydrophilic means love for water so they are soluble in water so part of this is soluble in water which is a polar head part and part of it is insoluble in water which is known as the fatty acid tail part which is insoluble in water so oils and waxes oils are very similar to polyunsaturated fatty acids oil oils are lipids that are liquid at room temperature and oils we produce act of a natural sunblock barrier to bacteria and lubricant and actors to begin for skin okay waxes are lipids that are solid at room temperatures oils and waxes are just solid in liquid parts of each their liquid when they are products that are you know produced to protect dust particles from entering our body so these waxes are produced so that some dust particles can be trapped in them and they they don't enter into our main system of our human body steroids and econo sides the steroids remember cholesterol is an it is a steroid and absolutely necessary for our body okay eggs have cheese milk have certain amount of cholesterol and we need cholesterol because the cholesterol is the building blocks of many hormones of many many other lipids that are necessary for our body there are these steroids are bile salts vitamin D sex hormones estrogen and testosterone are all steroids and there are added no cortical hormones so I'm going to go to the next slide and come back to this slide again so if you see cholesterol is the building block for testosterone formation and for estrogen formation in females so going back to the last unit which is a con asides lipid type to derive from our fatty acids is known as raccoon a tonic acids which is basically prostaglandins so these are econo signs no prostaglandin is an example of ikana sites which are present in our body then comes proteins proteins remember are absolutely the most abundant organic compound in our body our proteins they are the support they have many functions okay they give support and they form the framework also to provide strengthen our body different form of free work in the body collage and keratin etc are all examples of it movement there are several contractile proteins that are present in the muscle which help in contraction and relaxation of the muscles and these are nothing but proteins there are transport proteins hemoglobin transports oxygen in blood hemoglobin is a protein and that helps in the movement of oxygen they trap they basically hold the oxygen and carry it in the plan buffering they help in assisting the pH changes albumin acts as an acid and base to prevent why change in the pH in our body so fluctuation in the pH is controlled by proteins also catalysts several enzyme acts as catalyst bio catalyst to accelerate chemical reaction in cells regulation of metabolism there are growth hormones insulin hormones in general are important for a regulation or metabolism of our body and those are all proteins there are proteins which are involved in defense mechanism proteins called antibodies are components of the immune system help to protect us from a foreign matter and there are several clotting factors which are also for the protective mechanism they are involved to blood clotting there are proteins in them which stop bleeding in in the injury sites they are also part of the defense mechanism so proteins have apart from being the structural framework in the body they have many other functions also as you can see it in here so proteins actually is consulted by 20 amino acids and they have a combination of carbon hydrogen oxygen and nitrogen so these are they have a special structure and they are made up of amino acids of an amino acid as we just learned before have an amine group and carboxylic group also and we learn about the structure of proteins in the next slide but just to let you know that proteins do have carbon hydrogen oxygen and nitrogen which is very important to remember there are small proteins there can be large proteins small proteins in the range of 10 amino acids it can be 2,000 amino acids which are larger on macromolecules to form proteins and the proteins have different structures they can have primary structure secondary tertiary and quaternary structures and the shape of the protein actually determines the function of it okay how they form bonds how they function depends upon the structure of the protein and one of the most important example of it is hemoglobin which we will learn so the structure of proteins the building blocks of protein of amino acids so if you look in here so this is a the general structure of a protein so this is a carbon with its four bonds so remember this is these are the four electrons on the outermost shell and they form born with carboxylic group which is the acid group in here there is an amine group in here which is NH two and an age group which is of course here and there is an R group which is a variable this variable group means that it changes from amino acid to amino acid so basically rest of the group is saying it's only the artbook that changes so where if it is h it forms glycine when it is CH 2 co h it forms aspartic acid so the general structure remains our so only the variable R group changes in the now these amino acids they join together by the dehydration reaction releasing a water molecule to form what is called a peptide bond okay so this peptide bond when two amino acids joined together they form a bond which is known as the bottom tight bond and many many such amino acids joined together via the peptide bonds to form a protein okay so it can be xx it can be mm such peptide bonds are found and it depends upon different kinds of amino acid that they join together to form those peptide bonds the structurally the proteins as I said has primary structure second really interested in quaternary structure and the structure of the protein determines the function of it usually the 14 quaternary unit is present for in hemoglobin and hemoglobin actually is am sorry about that and hemoglobin actually is the three-dimensional structure on protein is important for its function because hemoglobin can needs oxygen to different parts of the body so proteins enzymes are proteins so remember all enzymes are not proteins okay so on and all the enzymes are not proteins but there are several enzymes which are proteins proteins are all proteins are not enzyme but enzymes are made many of the enzymes are proteins so they act as catalysts for the reaction okay so these enzymes usually end with the word ASE like catalase so they these enzymes are bio catalysts they lower the activation energy what is activation energy and just go over it but they these enzyme actually increases the of reaction so if you look in here you'll understand it better so I don't think I like that so this proteins protein in general actually act as to increase they are responsible to increase the rate of reaction in in a human body so they are known as a bio catalysts comes to the last section which is the nucleic acid so the nucleic acids are a large organic molecule composed of carbon hydrogen oxygen nitrogen and phosphorus so they have all of it carbon hydrogen oxygen nitrogen and phosphorus the two classes of nucleic acids are deoxyribonucleic acid DNA and RNA which is ribonucleic acid so DNA is deoxyribonucleic acid and RNA is ribonucleic acid so what is the primary role of these nucleic acid the primary role of nucleic acid is storage and transfer of information so they are mainly responsible for storing and delivering or transferring the information for the synthesis of protein so from DNA information goes to RNA and from RNA it makes proteins so it becomes the blueprint for protein formation so so they are the nucleic acid consists of one or two long chains our subunits of nucleic acids are known as nucleotides so it can be one nucleotide or it can be two nucleotides and a molecule of DNA is a chain of nucleotides so what is a nucleotide a nucleotide is basically it has a nitrogenous base a pentose sugar and a phosphate group so let's just and what each one of them is and we will learn about them in the next slide but right here I just want to show you this is showing you a DNA these are the nucleotides that are intervine double helix chain of nucleotides and here are the composition of the of the DNA so you can see it in here the nucleotides are made up of nitrogenous bases and it also has you can see the nitrogenous bases it's made up of it has bent or sugar and a phosphate group it has a bent or sugar and has a phosphate who will do in details in the next slide okay so that you understand it better okay so nucleic acids are macromolecules and they are they are made up of nucleotides we just learned there are two kinds DNA and RNA DNA is deoxyribonucleic acid RNA is ribonucleic acid and they are made up of several substances let's do each one of them okay it typical nucleotide consists of a phosphate group of sugar molecule and and a nitrogenous base okay so for example there are the nitrogenous base bases with one carbon nitrogen ring so there is nitrogenous bases along with it and they are as uracil thymine cytosine are called the pyrimidines and purines are adenine and guanine so they are of different kinds so let's understand this once more so they are DNA and RNA is made of phosphate group they have a sugar molecule and they have nitrogenous bases which is adenine guanine which are purines uracil thymine and cytosine are predominant so purine they are these nucleotides are made up of nitrogenous base which are of different kinds okay so what are they may there they have phosphate group they have a sugar muddy and they have a nitrogenous pool so so for DNA the sugar moiety is deoxyribose sugar and for RNA tis the ribose sugar so the ribose sugar in RNA when it has one less oxygen in them it forms deoxyribose sugar and that's present that sugar molecule is present in DNA for RNA the sugar molecule is ribose sugar both of them have phosphate group and and all for DNA the nitrogenous bases is ATG C which is adenine thymine guanine and cytosine and for RNA it is Aug C which is adenine uracil timing I mean adenine uracil guanine and cytosine Aug C okay so these are the differences between the two nucleic acid this actually shows you the the nucleotide composition this is the sugar moiety this is the time being soonest I mean this is the nitrogenous base in here and it is attached to a phosphate molecule also so these joined together by double helix in order to form a nucleotide so if you look in here these are the bases nitrogenous bases this is cytosine limit is this is guanine these are the phosphate molecule and this is the the ribose or the sugar molecule so for DNA it's a double helix and it these double helix nitrogenous bases and joined together by hydrogen bonding reform they usually join as adenine is joins with thymine guanine joins with cytosine ATGC that's how they join together to form a double helix they are interwined with each other irony on the other hand the nucleotide is single nucleotide and the bases are shown in here as Aug see they have uracil instead of the thymine in DNA this actually shows you adenine pairs with thymine forming two stabilizing with hydrogen bonding one in place pairs with cytosine forming the bond with hydrogen RNA molecules in general they contain ribose not deoxyribose they have uracil they are single-stranded and there are different types of them depending on their function messenger ribosomal and transfer RNA okay ATP adenosine triphosphate is a high energy compound ATP is required by muscles by cells to do all the functions it consists of it consists of three phosphate groups attached to adenine and five carbon sugar ribose sugar so this is an ID no sin and when it is trying to three phosphate then it's known address in triphosphate so this is adenine and this is the phosphate group so when it has three phosphate group attached to it it's known as adenosine triphosphate when it has two phosphate it is known as adenosine diphosphate then it has one phosphate group attached to it is known as adenosine monophosphate and all three of them are involved in energy as an energy compound but here we are more interested in ATP which is adenosine triphosphate and it is this it is the main source of energy for cell for all its function so these are these molecules these macromolecules are absolutely necessary for our body CEL makes ATP by using sugar molecules in order to form ATP there are other sources also like amino acids fatty acids can also form ATP to suffice the energy needs of the cell