foreign [Music] from your Milady cosmetology textbook this is a super exciting chapter it's actually one of my favorites because it is really going to nail down the properties of the hair and scalp of course coincidentally the name of the chapter properties of the hair and scalp this is an excellent chapter and it is very uh meaty there's a lot of information lots of science so we may break it down into two parts if we do you'll know part you'll notice the part one and a part two but for sure we are going to be talking about the properties of the hair and scalp so first I just want to bring reference to the fact that because this is a very science focused chapter I am going to work with the book open right next to us so you should see it on the screen along with the PowerPoint this is going to be a great way to identify vocabulary definitions directly copy and paste words that may be a little difficult to pronounce and really go along with the technical information learning the chapter is going to be so important it's vital to your career as a cosmetologist so our learning objectives today are going to be to identify and distinguish the different structures of the hair roots point out and differentiate the differences among the three main layers of the hair shaft identify and explain the three types of side Bonds in the cortex we're going to name and compare the differences among the three cycles of hair growth we're going to give real life examples of the common types of hair loss and explain what can cause hair loss we're going to identify and explain at least three options for hair loss treatment we're going to learn to identify the most common hair and scalp disorders that are seen in the salon and even the school environment and then we're going to name which ones a physician should treat and which ones you can work with and then we're going to compare and describe the different factors that should be considered during a hair and scalp analysis so as a cosmetologist there's a lot of science behind what you do it's not just about beautifying the hair as much as we love that it is important that we understand that as a hair stylist we pay a important role in many people's lives whether that's restoring their hair to a healthy State whether that's maintaining their natural healthy State Affair whether that's referring them to someone who could help them do both of those two things so in order to do that we have to be able to understand the properties of the hair and scalp so all her Services must be based on a thorough understanding of the growth structure and composition of hair so by the time you are done with chapter 11 you should be confident Consulting and performing a scalp analysis and identifying different structures of the hair disorders and maybe even a couple of diseases all right let's move right along and get started with some key vocabulary terms that you are going to want to know if it was me I would write these down but you know it's your world I'm just living in it so discovering the structure of the hair trichology is one of those vocabulary words that you're going to want to write down more than likely it's going to be asked in your state board exam trichology is a scientific study of hair its diseases and care let's go ahead and reference our textbook so that we can read the definition the scientific study of hair and its diseases and Care is called trichology which comes from the Greek word trials which means hair and ology which means to study up so trichology the study of hair the hair skin nails and glands are part of the integumentary system and although we no longer need hair for warmth and protection hair still has an enormous impact on our psychology so if you really think about it understanding trichology which is the study of hair it and its diseases in care is vital to your position as a licensed cosmetologist so in this chapter we are gonna dive deep into two very different structures of the hair that is going to be the hair root which is the part of the hair located below the surface of the epidermis the epidermis outer layer of the skin so we have the hair root which is the part of the hair located below the surface of the epidermis and then we have the hair shaft this is the portion of the hair that projects above the epidermis most of the time we are concerned with the hair shaft that portion of the hair that we see that is what I like to call the office right that's where you're doing the bulk of your work that is what you're manually manipulating that is what you and the customer in the world is seeing and then the hair roots the part of the hair that's located below the surface of the epidermis the outer layer of the skin it's something that we don't see that's what I would consider the back office let me tell you something about any good business no matter how good the hair shaft is manipulated or the front office is manipulated to look if the hair roots the back office is unfavorable it is unhealthy it is unorganized it is not up to scope then the whole business is a couple so three very important words trichology scientific study of the hair it's the uh it's diseases and Care the hair root which is the part of the hair located below the surface of the epidermis and then the hair shaft which is the portion of the hair that protects the epidermis so from there we're going to talk about the structure of the hair roots the hair roots our back office is going to contain air follicles which work to do the distribution and the growth the hair bow the dermal propeller the erector pili muscles and the sebaceous glands the hair root is the two black depression or pocket in the skin or scalp that contains the hair wound itself hair follicles are distributed all over the body with the exception of the palms of the hands and the soles of the feet so now you can't see me now but when I when you say that to yourself I want you to understand that the hair root is I'm sorry the hair follicle is a tube-like depression or pocket in the skin or scalp that contains the hair of roots there are hair follicles distributed all over the body but with the exception and I want you to touch the palm of your hands with the exception of the palm of your hands and the soles of your feet so we have hair follicles the tube like depression all over the skin and scalp with the exception of the soles of our feet and the palms of our hands the follicle extends downward from the epidermis into the dermis which is the inner layer of the skin where it's then surrounded surrounds the dermal papilla sometimes more than one pair will go grow from a single follicle so then you have the Hair Bow which is the lowest part of the hair strained it is the thick end it is tube shaped and structured and it forms the lower part of the hair root the lower part of the hair bulb fits over and covers the dermal Papua we'll then have the dermal papilla or papilla it is a small cone-shaped elevation located at the base of the hair follicle that fits into the hair bulb the drama papilla contains blood and nerve Supply that provide the nutrients needed for hair growth some people will often refer to the dermal papilla as the mother of the hair because it contains the blood and nerve Supply that provides the nutrients needed for hair growth so an ineffective unhealthy Derma propeller will show up as lack of growth and overall health to the hair itself you then have the erector priline muscle which is the small and voluntary muscle in the base of the hair follicle involuntary meaning it does its work without a thought from us strong emotions or cold sensation cause it to contract which makes the hair stand up straight and results in what we call Goosebumps we typically notice this with the hair on your arms lastly in the structure of the hair root you have the sebaceous gland and these are the oil glands in the skin that are connected to the hair follicles the sebaceous the sebaceous excuse me glands secrete a fatty or an oily substance called sebum sebum is what lubricates the skin you'll notice that you will have clients with very active sebaceous plans meaning they have a lot of oil production they typically have to wash their hair more often it will get oily or weighed down if they don't and then you have clients who don't have as much fatty or oil substance known as sebum produced and their hair will tend to be a little more dry less oil production is going to sometimes show up as drier or rougher of a texture of a hair so you want to take note of the structure of the hair roots so that you know what it is composed of so it's the Epic right under the epidermis and connects through to the dermal layer it is the back office of hair it is the part that we do not see then we get to look at the components of the hair shaft there are going to be three parts this is a hint here three parts you're going to want to know this information of the hair shaft that's the cuticle the cortex and the medulla a little bit about the hair cuticle it's the outermost layer of the hair so it is the hair the portion of the hair in the office area so that's the hair that we see the hair that we manipulate that you can feel it is the outermost layer of the hair and it can consists of a single overlapping layer of transparent scale-like cells that look like shingles on the roof the cuticle layer provides a barrier that protects the inner structure of the hair as it lies tightly against the cortex so you've got the cuticle outer layer that is a protects protects that inner structure of the hair that is called the cortex so we'll go let's give a little bit over and let's go into the cortex the cortex of the middle layer of the hair it's a fibrous protein core formed by elongated cells containing melanin pigments so the color of the hair is kind of is redeveloped from the cortex about 90 of the total weight of hair comes from the cortex so you have the hair cuticle the outermost layer very thin layer protects the cortex which is right up under the cuticle it is about 90 of the total weight of the hair and it is a fibrous protein formed by elongated cells containing melanin pigment the elasticity of the hair and its natural color are the result of the unique protein structures located within the cortex so everyone's cortex is comprised of that same roughly 90 percent of the total weight but because of the unique protein structure located within each individual's person's cortex that is how we're determining elasticity that bounce Snapback um structure of the hair and the natural color of the hair then you have the medulla that is the third structure of the hair shaft it is the innermost layer of the hair and it's comprised of round cells it is quite common for very fine and natural blonde hair to entirely lack the medulla so the finer the hair and the lack of melanin typically indicates a client with a lack of a medulla so that lack of that innermost layer of the hair shaft generally only thick coarse hair contains a medulla all underline all male beard hair contains a medulla which is honestly really interesting because the body is just so smart like I just didn't know how does the body know to form that you know it's like it's something that's so well beyond the scope of what you think about when you think about the hair and doing hair and being a cosmetologist the hair shaft is comprised of three really key components that determine what it is we see so I really want you to take note on that and I want you to write down the structures of the hair shaft they contain the cuticle cortex and medulla and then just to back up a little bit the structure of the hair roots contain the hair follicle which is responsible for distribution of growth the hair bow the dermal Papillion the erector pili muscle and sebaceous glands and now let's move up there we go let's make sure we're on the right slide here learning about the comp the chemical composition of air so the hair is approximately 90 protein and this protein is made up of a long chain of amino acids which in turn are made up of elements so these elements that make up the human hair are carbon oxygen hydrogen nitrogen and sulfur go and write those elements down we've got carbon at 51 percent oxygen at 21 percent hydrogen at about six percent nitrogen 17 and sulfur about five percent these mix of elements are often referred to as cone elements cones elements are going to be the makeup of the long long chain of ass amino acids that are then turned into the protein that make up about 90 percent of the hair so these five elements are also found in the skin and nails I would take a moment to just screenshot or go ahead and write down the five elements and their percentages and then reference the fact that about 90 the hair is about 90 protein so I've got the elements pulled up on the screen all the elements are on the screen and you're writing that down I do want to talk to you a little bit about the chemical composition a little more in detail so the hair is composed of protein that grows through cells originating within the hair follicle this is where the hair begins so in the hair follicle the first structure that we talked about the back office that's where hair growth begins as soon as these living cells form they begin their Journey upwarded Through the hair follicle and they mature in a process called keratinization so as soon as these newly formed cells mature they fill up with the fibrous protein called keratin which is the process of keratinization and then after they filled with carotene the cells move upward lose their nucleus and die so in the hair shaft I'm sorry in the hair follicle the process of character civilization starts which is newly formed cells mature they fill up with a fibrous protein called keratin after that fill-up process of the Keratin has taken place the cell is slowly moving upward then they will lose their nucleus then they will die by the time the hair shaft emerges from the scalp the cells of the hair are completely character keratinized so they are no longer living the Keratin has completely formed and threw that cell and they are no longer living and then the hair shaft that emerges is a non-living fiber compost of keratin protein so that hair strand is about 90 protein and for that to happen the process is called keratinization so the hair starts off in the follicle it grows and it goes to this upward Journey Through the follicle where we can't see it it's in that back often back office and then that hair once that process has taken place it's filled with keratin the cells move up up and up they lose their nucleus and they die once they emerge from the scalp once they emerge and we can actually see them they are no longer living and is made up about 90 percent keratinized protein so remember the elements that we talked about the cones elements carbon oxygen nitrogen I'm carbon oxygen hydrogen nitrogen sulfur I'm sorry I want the same in order that is the elements that are making up that 90 of protein okay let's go down we've got characterization we talked about that the maturing process of living cell that originate within the hair follicle all these newly formed cells mature fill up with the fibrous protein called keratin and grow mature push out die and then we get to see them as our hair let's talk a little bit about amino acids the proteins are made up of long long chain amino acids which are units that are joined together end to end notice the hollow peptide chain here showing them connected into ink they are a strong chemical bond that will join the amino acids to form a peptide bond also known as an in-bond so you may see it as a peptide bond or an end Bond and then a long chain of amino acids linked by those peptide bonds is called the polypeptide chain so these proteins are a long coiled complex polypeptide which are made up of amino acids the spiral shape of a coiled protein is called a helix write that down the spiral shape of a coiled protein is called a helix which is created when the polypeptide chains intertwine with each other so then you have the side bonds of the cortex the cortex itself is made up of millions of polypeptide chains those polypeptide chains are cross-linked like the rungs on a ladder by three different types of side bonds so you have the cortex that's made up of millions of peptide polypeptide chains those polypeptide chains are then cross-linked like you would see the rungs on the ladder by three different types of side bombs so your side bonds are going to be hydrogen bombs salt Bond and disulfide bonds so these side bounce that link the polypeptide chains together are responsible for the extreme strength and elasticity of the human hair and they are essential to services such as wet setting thermal styling permanent waving and chemical hair relaxing we'll talk a little bit more about that in chapter 20 of the chemicals texture services but the three types of salt bonds are the hydrogen salt and disulfide box okay so let's define each of the three bonds so hydrogen bomb is weak physical Cross Lake Side bond that is easily broken by water or heat although individual hydrogen bonds are very weak there are so many of them that they account for about one-third of the hair's overall strength so about one-third of the overall strength of your hair is from the hydrogen bonds hydrogen bonds are broken by wetting the hair with water and that allows the hair to be stretched and wrapped around rollers the hydrogen bonds reform when the hair dries you can have a salt bond which is also a weak physical cross-link sided bond between adjacent polypeptide chains so salt bombs depend on ph so they're easily broken by a strong alkaline or acidic solution even though they are weak bones they are so many of them that they account for about another one-third of their overall strength so you've got hydrogen bonds that are cross-linked and broken by water and or heat you have salt bonds which account for another one-third and these are dependent upon the pH so they are broken by strong alkaline or acidic Solutions then you have disulfide bonds which is a strong chemical side bond that is very different from the physical side Bond of a hydrogen bond or salt so of the three hydrogen and salt are both physical bonds and disulfide bonds are a chemical bond so this is the stronger of the three and is the chemical side bond that is different from both physical salt and physical hydrogen bonds the disulfide bones join the sulfur atoms of two neighboring site psychisting amino acids to create one cycysteine I'm gonna go ahead and verify the pronunciation of size 16 c-y-s-t-i-n-e so if you haven't seen this yet I have a little trick that I like to use and it's c-y-s-t-i-n-e and I'll just go to Google I'll type pronounce and the word and then I'll play it so let's do that Sistine Sistine so not size 16 it's just sustainable cysteine cysteine box so if you've ever been struggling with the pronunciation of a word I would go Google pronounce and the word and it will pronounce it for you so I had that wrong so let's read that line again the disulfide bonds join the sulfur atoms of two neighboring cysteine amino acids to create sustained bonds so the cysteine joins together two polypeptide strains and although there are far fewer disulfide bones than hydrogen or salt bonds disulfide bonds are much stronger that they also account for one third of the hairs overall strength so there are less of them but they still account for one-third of theirs overall strength disulfide bonds are not broken by water they are broken by permanent wings and chemical relaxers that alter the shape of the hair so hydrogen bonds salt bonds you can consider those temporary changes to the side bonds of the cortex the cortex baby hair and then you can consider a disulfide bone a process that is chemically creating a change in that side bond by a permanent wave or chemical hair relaxer so chemical type service is going to be necessary to perform that hey here is a little cheat sheet for the bonds of the hair you can take a picture of this so that you know the three side bonds and then the one in the bond which is a peptide so you have bonds of the hair side bones hydrogen side bonds salt side Bond disulfide two of which are weak physical bonds which are hydrogen assault one of which a chemical or a strong and a strong bond disulfide let's pick up to go into hair paper so all natural hair color is the result of pigment located within the cortex melanin and the tiny grains of pigment in the cortex that give the hair the natural color there are typical there are two types of melanin and those are you melanin and phenome so let me go and play then just to make sure I've got them right so you know on them you melanin melanin and feel melanin Theo melanin so you melanin and Co melanin your melanin provides dark brown or black hair color and Theo melanin provides yellow to Red Ginger cup natural hair color in a person's hair is due to the presence of the mixture of these pigments new melanin gives darker hair and the amount can vary from person to person and also across a person's head so their entire head can have various shades of a color when we look at the hair under the microscope the EU melanin pigment granulars are typical oval or elliptical in shape and the field melanin pigments are partly oval and partly broad-shaped gray hair contains only a few scattered melanin granulars and white hair does not contain any so remember we talked about the hair having cortex so let's go up to it we talked about the hair follicle we talked about that I'm sorry not there fog we're talking about the hair shaft and the components of the shaft being the cuticle of the cortex and the medulla so remember which of those three that if it lacked a medulla then the hair I gave it away which of the three which is the medulla if it lacks that in the hair then it would not contain pigment so a client with either no hair pigment also a clown with white hair is not going to contain any melon melanin which means they are more than likely not going to contain a medulla what you want to take from this is the overall shape when looking under a microscope and the different color types so uh you melanin provides natural Brown to black and it is going to have a pattern under a microscope of oval or elliptical in shape and free melanin is going to be pigmented pigments that are typically lighter in color they're going to range from red to and ginger to yellow and blonde tones and hair lacking any pigment at all white hair is going to lack the medulla in the hair things away and then we can talk a little bit more about wave patterns of the hair excuse me the wave pattern of the hair refers to the shape of the hair strand it is described as a straight wavy curly or extremely curly you see that from figure 11 9 so we have straight wavy curly or extremely curly natural wave patterns are the result of genetics and although there are many exceptions as a general rule Asians and Native Americans tend to have extremely straight hair Caucasians tend to have straight wavy or curly hair and African-Americans tend to have extremely curly hair sometimes even coiling but straight wavy curly and extremely curly hair occur in all Races any one of anyways or mixed sprays can have hair with 30 degrees of curl from extremely straight to extremely curly or even coily the wave pattern may also vary from strands to strand in a person's head so just like pigment just like color genetically a client will have multiple patterns and multiple colors in their hair when we're considering a wave pattern so it's important to understand that it will vary from person to person and within the same person's head it can be a very rare case I mean a very mild case of variation and it could be entire sections that have lots and lots of variation it is not uncommon for an individual to have different amounts of curl in different areas of the head an individual with curly hair often have straighter hair in the crown of the head and Tighter curl in other areas straight blonde hair is round with morpheo melanin great black hair is round with mostly human and straight gay braid hair black smell onion all together and then curly hair is typically oval in shape [Music] all right so just take a moment to take a look at the photo on the screen the basis of hair color and texture you've got a straight bond with Phenom melanin you've got a curly bond with emailing in straight black or brown curly black or brown straight gray curly gray and you've got that that cuticle that cortex and that medulla that form so notice in the straight gray curly gray you are lacking that obvious medulla hair growth as our next topic is actually super super exciting because swim doesn't love hair growth the two main types of hair found on the body are Bella's hair and terminal hair Bella's hair and you're definitely going to want to write this down Bella's hair also known as Lango hair is short fine unpigmented and Downy hair that appears on the body Bella's hair almost never has a medulla the hit there is that it's often not pigmented it is commonly found on an infant and can be present on children until puberty on adults fellas hair is usually found in places that are normally considered hairless so the forehead the eyelids and a bald scalp typically nearly all hair all other areas of the body except the palms of the hand touch them soles of the feet the follicles that produce the vellus hair do not have sebaceous glands then you have the second type of hair which is found on the body and that is terminal hair this is long coarse pigmented hair found on the scalp legs arms and body of males and females don't get confused because we it's described as long coarse and pigmented not all hair will be pigmented it's just a characteristic of terminal hair as opposed to vellus air that's going to lack that pigment some people will have terminal hair with pigment and without so just to clarify terminal hair as a characteristic as a type of hair is long course can be pigmented and is found on the scalp legs arms and bodies of males and females terminal hair is coercive and Bella's hair and with the exception of gray hair is pigmented it usually has the medulla it's important to understand that hormonal changes during puberty can cause some areas of fine bellus hair to be replaced with thicker terminal hair all hair follicles are capable of producing either vellus or terminal and it's going to depend on the genetics age and hormones so much like puberty is a major factor in people's lives you'll notice that as people age people go through pregnancies people go through other hormonal changes that that can infect their hair growth that hair grow can affect the hair anywhere on their body of course up until including the hair on the head which we will most likely continue with thank you from here we're going to talk a little bit about the cycle of hair the growth cycles and that process earlier we talked about the hair coming out of the clients head so the hair being within the epidermis and what that is called or the hair shaft and the hair follicle the hair root and then we talked about the hair coming out and the hair being the hair that we saw it's important to know that that process is considered a growth cycle so hair growth occurs in cycles and each complete cycle will have three phases and these three phases are repeated over and over throughout one person's life the three phases are antigen catagen intelligent go ahead and write those down the three phases are going to be antigen categy intelligence something important to note about that is antigen is the growing phase catagen is the transitioning phase and intelligent is the resting phase so once the hair has gotten to the point where it has died and it is now the hair that we see it is no longer in the fault or we are seeing the hair then it is considered in the resting phase because remember it is dyed just for fun let's look at some myths and facts about the hair myths shaving clipping and cutting the hair on the head makes it grow back faster darker of coarse that is a fat shaving or cutting the hair on the head has no effect on the growth when the hair is blunt cut to the same length it grows back more evenly so although it may seem to go back faster darker or coaster shaving or cutting the hair on the head has no effect on its growth speed remember the myth is that oh if I shave if I clip or if I cut the hair on my head it's going to grow by faster or serve darker that is not true and that's the same with blanks that is a myth the fact of the matter is the hair has to go through all three Cycles save the Cycles with me antigen growth phase catagen intelligent transition phase intelligent resting face that process is determined by age and genetics and overall health so it's going to grow back the way it's going to grow back it is not going to be affected and make it darker coarser or any anything like that another myth scalp massage increases hair growth the fact is Scout muscles are very stimulating to the scalp and can increase blood circulation relax the nerves and scalp and tighten the scalp muscles however it has not been scientifically proven that any sort of stimulation on the scalp increases the growth so it's important to know that although scalp massage is stimulating and can help contributes a hair growth it is not scientifically proven that that is the process that happens so I'll let you go through and take a few minutes just kind of look up some other facts and some minutes you can research this a little more in your textbook but essentially there are so many myths out there there's so many facts out there the best way to contend with that is to understand what we're understanding now the properties of the hair and scalp how they work and the growth Cycles the formulations what type of what it's made of the protein the type of side bonds that are uh and how they affect the cortex of the hair all of those things help you understand if something is in fact true or false and something that we can kind of just let go of so we're actually going to stop this part here just as a recap we have went through a couple of good pieces of information and I would encourage you to go ahead and read up into this point in the chapter we have gone through the structure of the hair which are the hair roots shaft and follicle and what those three structures consist of when appropriate we've talked about the therapeutical the cortex and the medulla we've talked about the build uh what the hair is composed of the 90 protein and the cones elements that make up that 90 protein we talked about new cells being formed and how that maturing process works we talked about the fibrous proteins called keratin and the process of keratinization we talked about amino acid than the end bonds and the polio peptide chains as well as the Helix of the hair we talked about side bonds of the cortex those hydrogen salt and disulfide bonds we also talked about the pigment in the hair the EU melanin and the Phenom melanin how great and or blonde hair can tend to have no melanin we also finished up talking about the two types of hair that is available to on the body being velas hair and terminal hair and then we finished this segment talking about the hair growth Cycles which are going to be three antigen catagen intelligent so go ahead and read up into this point in your textbook if you haven't already done so during the presentation or after before the presentation and in the next part of this we are going to close out the properties of the hair and scalp talking about hair loss treatments fungal infection fungal infections hair density and some key takeaways for the chapter it's been a pleasure and I hope you learned a lot [Music]