Free Biology NEET Video Lectures for Human Reproduction

00:00:02 [Music] so [Applause] [Music] [Applause] [Music] let's get started uh so today we will discuss about human reproduction and uh in this topic we'll try to cover about the male and the female reproductive system and what are the different organs are involved in the system we'll try to try to understand the whole topic in in that way so before starting a human reproduction uh one has to understand the actual aspect of reproduction so every uh living individual can perpetuate his own generation by a process of reproduction

00:01:06 so the whole animal kingdom is divided into various forms based on the birth pattern how they are giving birth to the young ones are basically categorized into different types and accordingly we can define the different varieties of animal species so there are species of animals which are giving directly birth to the young ones and those are called as yb pearls so why we paris animals are the one which are giving birth to the young ones the second varieties are ohi paras now this ovi paris animals are

00:01:55 the one which are giving egg so they are egg laying animals they are laying the eggs outside environment and egg as such is getting developed outside uh the body so they are not developing uh the young ones inside the body but basically they are laying the eggs outside and the egg is getting developed into a young ones later on outside uh the body well we have the mixture of these two and we called it over vivi paris and in overweight prepares animals the egg-laying animals but the egg is not laid as such the egg is getting

00:02:48 developed inside the body and the young ones are getting hashed out young ones are getting bird or young ones are getting out from the body so basically they are egg-bearing animals they are having eggs but the eggs egg is getting matured inside the body and they're giving birth to the young ones so for example there are many fish varieties are there there are many insect varieties are there so the amphibians are also following this pattern where the egg is getting matured inside the body and they are giving

00:03:20 birth to the young ones so the basic difference between these all species now here the viviparous animal are having connectivity we call it the connection is there in the body where the fetus the young one is getting nutrition getting some nourishment from the mother's body body while in case of ovi paris animals there is no connection as such so the egg is coming out and then all the development is taking place in the egg while in case of overwatch animal there is no connectivity in the body as such but the development is

00:04:08 taking place inside the body so there are a couple of example as i said we have some fish we have certain varieties of amphibians we have some insects so these are the three modes of reproduction so all right we will move on and try to discuss that what are the important uh organs involved in this human reproduction so let's try to understand it first and then we will jump into the individual organs as such now when we are talking about the reproduction when we are talking about the human reproduction particularly we

00:04:55 have two things in mind the sex so there is a clear-cut sexual uh differentiation in human being so one can nicely differentiate that person is male or or another one is female so let's start with this one and then we'll try to understand this one from from the organ point of view so we have male and then we have female so these are the two distinct sexual kind of individuals available in human kingdom in the human being actually as such so the male and the female are having very specific

00:05:37 organs various specific kind of system available for reproductive aspect the organ which are involved the organ which is involved in the male reproductive system we call it testis so there are two testes actually so a pair of testes and similarly in case of female we have ovary so we have ovary as a reproductive organ in case of female and we have testes in case of male now these testes are responsible for the production of a very unique form of cells which are which are the first cell of the human

00:06:25 body actually this is the after joining these are forming the first cell of the body but the one which is coming out from the test is we call it sperm and this sperm is nothing but the male gamete so we are calling it as a male gamete or male cell reproductive cells actually so milk reproductive cell counterpart is sperm and in case of female we have ova so these are the productive organs so they are ova is produced in ovary and the sperms are producing testes now the the process of formation of this sperm intestines is called

00:07:11 spermatogenesis spur metal and genesis means formation so there will be a formation of a sperm by a process called spermatogenesis and the organ involved is called testis and is is there in male similarly we have ova formed by a process called oogenesis and um the the formed product is called ova and it is formed in an organ called ovary so we have this two distinct gamut one is from male side and one is the female side these two gametes are formed by these two process and collectively these two process is called

00:08:02 this since these are gametes so they are called as gametogenesis gamma 2 genesis so these this process is formation of gametes so male gamete we called sperm and the female gamete we call ova and the whole process is collectively called as gametogenesis the gametogenesis in case of male is called spermatogenesis the gametogenesis in case of females are called as oozinesses the formation of ova actually so this is the first stage actually so there will be a formation of gamut now the gametes are formed in these two

00:08:41 distinct kind of sexual dimorphism we are calling it so we can nicely distinct that these these this is male and this is female in case of human being so now we we are talking about that so in male we have a sperm and in female we have ova now there will be a process in order to mix these two things so the process of transfer of the sperm into female reproductive system in order to fuse sperm with ova is called insemination so we have process called insemination so insemination is a process of transferring of sperm to the female

00:09:40 reproductive system in order to fuse over uh with sperm so this is a process called insemination after insemination now we will see the structure of the sperm anova in our later discussion later classes but we need to understand the gross picture what is happening and what we are going to talk about in in this whole topic so first we need to understand what are the gametes then how these gametes are getting developed how this gamete are getting transferred so the first the the male gamut has to transfer into

00:10:16 the female side because the actual uh individual the actual person who is going to deliver a baby is a female counterpart so something needs to be transferred from the male side so that it can fuse in the female body so the sperm is getting inseminated the terminological insemination so sperm again is getting transferred into the female reproductive system and the sperm and ova is getting fused and after fusion the fusion the process of fusion is called fertilization fertilizerization so the fertilization is a process of fusion

00:10:57 so this is a process of transfer and this is a process of fusion so now the male and the female gametes the sperm anova are getting fused are getting mixed and this process is called fertilization and after fertilization there the earlier these these were two cells now try to understand here so you have a sperm here as a single cell we have ova as a single cell now these two cells are getting mixed and forming a single cell now the single cell that is formed after the fusion of male and the female gamete is called zygote

00:11:41 so this is zygote so zygote is nothing but the mixture of male and the female gamete so male plus female gamete is called zygote so zygote as such is considered as the first cell of the human body because this particular cell is going to develop into a complete organism a complete individual complete human beings we are talking exclusively now about human reproduction so we need to understand here that this is the first cell of the human body and this particular cell is going to form a complete individual after division so

00:12:24 this particular single cell is going to divide into various forms so now what is happening so this is the process of fusion fertilization and after that what we are getting is called zygote now so we have zygote now so zygote is the first the single cell formed by the fusion of male and the female gamete this zygote is undergoing various kind of division various multiplication cycle rapid multiplication slow multiplication and all so a lot of multiplication is going on because we have many cells

00:13:13 right we are complete grown up mature individuals we have huge amount of cellular population we are talking about the first cell this is a single cell this needs to multiply in many form so that to form a complete individual right so there will be a complete division we will discuss about that division which is called cleavage actually so the cleavage is going to form various kind of a structure and after that this zygote is getting first stage after certain multiplication this zygote is getting attached to the mother

00:13:45 uterus so the actual area where the baby is getting developed this is called uterus butyrus so uterus is an area where the the baby the fetus the the young ones is getting proper development so there should be a connection right we need to connect it this zygote needs a proper connection with the human body or the mother body particularly so that to get all the nutrition so as to get the blood supply so as to get the all the required information required things in order to do multiplication right for that reason uterus is getting

00:14:25 kind of attachment so you suppose this is a wall of uterus so the wall of uterus is getting attached with this dry goat and this attachment is very important because this attachment is providing all the nutrition to the growing zygote because all the available nutrient is coming from the mother side so this is mother's uterus and the the whole information is getting into this zygote this process is called implantation implantation so implantation is nothing but attachment of zygote to the mother womb

00:15:02 or mother uterus in order to do a proper development and once the uterus implantation is fixed then after getting proper nutrition and all this zygote is started multiplying and after proper multiplication many multiplication cycle there will be a complete grown-up fetus here so the young baby actually is growing in this uterine cavity and this particular grown-up baby after like a period so let's see here now what's happening so so let's delete this part so after implantation what is happening that the

00:15:46 mother is providing complete nutrition to the growing young one and this growing young ones earlier it was zygote now it is growing going to develop right and there will be a time scale it's not like one day process not like two days process but there is a time is frame for example in case of human being we have nine months time so in nine months time this one cell will be completely developed going to develop into a small young ones right that's period is called gestation period so gestation period is a time duration

00:16:26 where the zygote is getting complete maturation inside the mother uterus and this time period is very specific for an individual animal for example as i said earlier the example in case of human being we have nine months in other species we have other different time scale so this gestation period after completing the gestation period the young ones are getting proper development the young ones are getting matured and once the young ones are getting complete uh division and what we call the specific terminology i am just using

00:17:04 that terminology not to confuse with ah because we are going to discuss this one again and again the proper uh terminology is called organogenesis so after the formation of organ so the formation of organ is called organogenesis so once this individual which is uh who is growing inside the mother uterus is getting proper development like proper liver and everything there there will be a birth of a young child so young one is coming out and the process of giving birth is called punctuation punctuation so this is

00:17:42 birth right now so we will try to understand this whole uh phenomena in a different style so the first stage what we discussed is the proper male and the female gametes so male gamete is called sperm and the female gamete is called ova these two cells are formed by a process called gametogenesis in case of females it is called oogenesis in case of male it is called spermatogenesis so they are forming sperm and over accordingly to different after formation these two cells are getting fused right

00:18:21 so before fusion one has to transfer the sperm or sperm is getting transferred from male body to the female organ female reproductive system and the process is called insemination and after insemination the male and the female gametes are getting fused by the process called fertilization and after fertilization we are getting a single cell and the cell is the first cell in the human body it's calling zygote and after that zygote formation this zygote is getting attached to the mother body and the particular area

00:18:55 where these are getting attachment are called uterus so in uterus they are getting proper attachment uh i am not going to discuss this particular terminology this is called placenta the attachment is called placenta so now this is now started getting all the nutrition and other things from the mother's body and after a proper time interval after a proper gap of time and that time interval is called gestation so gestation period is a complete developmental complete embryonic developmental stage in in case of human

00:19:27 beings so now after gestation period the the body and all the organs and everything is getting matured getting developed everything is done now that there is a time to get the young ones coming out from the body of mother and that that coming out process from the mother's body is called punctuation and this is nothing but the birth of a young one so this is in total what we are talking about the human reproduction so let's start with the male reproductive system so we will discuss about male first

00:20:02 so male reproductive system comprises of a pair of testes so ductal system so we have lot of ducts involved in this reproductive system some glands are also involved right so in total we have testes a pair of testes we have ductal system and there are certain glands let's start with the testes first so a testis is a very sensitive organ a male reproductive organ is located in the pelvic cavity so the location of this male reproductive system and female reproductive system both actually is in

00:20:56 pelvic cavity so the test is is as i said it's a very sensitive organ located in a very unique sec like a structure outside human body actually this is not outside human body but this is protruded out in the human body so this is singular we are calling it testis and in plural because they are paired so they are called testis tsts and the sag-like structure that is giving this uh test is as a proper accommodation is called scrotum so scrotum is a particular sac like structure giving accommodation to testis

00:21:41 now why we are saying that the testis is located outside the abdominal cavity outside the human body so this is located in in not with an actual attachment with the human body this is always in the bottom this is always outside the human body now why this is important because the testis as such is an organ which is responsible for the production of the sperm no production of a sperm you require 2 to 2.5 degree centigrade lower body temperature right so you need a lower body temperature lower temperature so lower temperature is

00:22:23 required in order to make the sperm in the tasties so spermatogenesis the process we that we discussed now uh just a few minutes ago that we have a process called spermatogenesis now spermatogenesis requires a lower body temperature because of this reason this testis is located outside the human body to make the temperature down as compared to the normal body so generally this is about 2 to 2.5 degree centigrade lower as compared to the human body so this sac is very important this is giving protection and also a proper

00:23:01 covering and all in order to reduce the temperature of testes in to make more sperms but here there there will be a tube like a structure as as i discussed that we have lot of tube duct-like system and all so this tube-like structure is called wasp difference this is called difference so this vast difference is a ductal system that is coming out from the testes right and this testis is giving passage to so sperm is getting formed and transported with this with the help of this duct system which is called vast

00:23:40 difference now this vast difference is coming back to so this this is going back to the pelvic cavity this is outside the body and then this whole structure is inside pelvic cavity this vast difference is connected to a very specific gland and actually this is opening into a very specific gland like a structure and this gland is called prostate so prostate is a glare and this gland is giving attachment to different ductal system one ductal system is vast difference there is another opening of an another

00:24:20 gland this is called seminal recycle so this gland is called seminal recycle so let's delete and write it somewhere else so we have prostrate here and this is called seminal vesicle seminal vesicle [Applause] so seminal vesicle is another gland this is giving also the opening into this crosstreat so this this curve this is common passage and in this prostate the whole ductal system is coming out and then mixing with another ductal system and that is a common passage for the urinary system also so this is getting attached to the

00:25:11 duct system which is coming from the urinary bladder so suppose this is kidney and this kidney is what we have discussed that you have the urinary bladder and then this is a kind of urethra so basically this is what is continuation of urethra so this is nothing but urethra so what is happening here that the whole ductal system is coming out in the form of a opening and dot opening is common for both reproductive system as well as excretory system here this ductile system which is giving passage

00:25:54 is a unique structure where the glands are involved now around the passage there will be another gland associated with this lubrication process so there will be another gland associated structure here in the passage of the tubes that carries the sperm and this is nothing but bulbourethral gland balboa urethral gland so bulbou urethral gland is also taking part in the pro in the whole male reproductive system where the whole sperm which is coming out from this testes is getting lubricated by the

00:26:42 fluid secretion coming out from this glandular structure this sometimes this particular gland is also called as cowper's gland calpers gland there is a proper covering of this whole structure and this whole structure the whole muscular mass that is giving opening to this urethra outside the human body is called penis and this is nothing but the organ that is giving passage to the urinary system as well as sperm coming out from the male reproductive system so let's discuss about testis now

00:27:25 so this test is is a roughly a very unique organ so if you see the lengthwise it is approximately four to five centimeter in length and in diameter is approximately two to three centimeter approximately so ah this these are just an approximation so this is also approximate length and approximate width now this is a very fragile organ and ah and this is the outer covering we called it scrotum if we see this test is there are lot of compartments actually inside this testing so these are divided into many compartments

00:28:13 small compartments here this particular kind of compartment is having lots of ductile system so in in human testing there are many compartments as i said approximately there are 250 compartments approximate compartment 250 and each compartment is having more than three sometimes three more than three also unique ductal system and this these ducts are called as seminiferous tubules semini ferrous tubules these seminiferous tubules are taking the sperm with a very unique kind of ductal system and this ductile system is called reti

00:29:08 testes so this ready test is is continued by another ductal system here so ah we can see lot of ducts are involved here so there were a mess work of the ductal system we called it retty testes and then we have another ductal system which is called vas efferencia efferencia so vas differentia is nothing but the ductal system giving connectivity of retice testis to another structure which is another coil like structure or miswork of the ductal system and this structure is called ap d diamonds so what is happening that we have the small

00:30:00 compartments we have 250 compartments as such there are many more also so approximately 250 compartments are there and each compartment is having three or more seminiferous tubules and this seminiferous tubule is getting connected to a meshwork of an area which is called retitastis this ready testes is continued by the with the help of a very unique ductal system called vas efferentia and this vas efferentia is um continued into another ductal area called epidermis and this epidermis is getting continued into another ductal

00:30:40 system and that's what we discussed just few minutes back that this is called vas difference so uh whatever we discussed about the human reproduction um let's try to see it in in a nice diagrammatic and pictorial representation here so this is a complete human reproductive system and if we see this is testis and this test is is connected to this ductal appearance which we called ep the dymas and this epidermis is basically getting continued with this ductal system so this ductile system is called vas

00:31:26 difference so this bus difference is the duct that is communicating from another glandular structure and this is what is going again and this is merging to the ductal system of the gland so now we have this gland that is called prostate and there is another gland here which we call seminal vesicle seminal vest cycle so the seminal vesicle prostrate are the two glands which are giving their ejaculation or their their secretion um into this ductal system so this vast difference is actually getting

00:32:08 the secretion of um the the glands and the gland is prostate and seminal recycle now this duct is getting continued here so basically this duct is getting continued in this area and then this is passing here in the form of urethra and then this ductal system is uh having another gland in in due course of communication to the outside and that gland is called bulbo urethral gland and this is also what we discussed is called copper gland so these are the three gland like structures in the human reproductive system the

00:32:54 first one is a prostrate ah seminal vesicle and you bulgo ultra van and these are secreting all their secretion into this vast difference that is coming out in the form of urethra to the outside environment now if we see uh here that we have another um a huge kind of mixing of the glandular system or mixing of the or the organ system now if you see in in the top of prostate gland we have this big area and that is nothing but the urinary bladder and that's what we discussed in our in our lecture that we have mixing of urinary

00:33:38 system and the reproductive system and both the ducts coming out from the urinary system and the reproductive system has a common outward opening in the form of urethra now here this is what is coming out in getting some urine that is filtered out from urinary bladder and then this is mixed up with the secretion which are coming out from this accessory gland as well as this testis so testis uh secretion uh in the form of a sperm and this testicular gland in the form of all ductal system and all glandular

00:34:16 secretions are mixing uh and coming out with this outward opening which is called urethra now this part which is giving opening to urethra or opening outside is what we call is penis and in in the in the flap and in the in the last end this particular area is called prepuce sometime it is also called as foreskin this is just an outside area that is giving a flap like hanging area the skin area outside is called tripus or sometime it is also called as foreskin while there is another huge muscular area here that is a kind

00:35:01 of just beneath the prepuce the area is called glance penis and this is another muscular area that is there at the external opening so in total this is about the complete human reproductive system where we have a complete gland ductile system and a specific organ that is called testes that is producing sperm so after looking into uh this whole structure of human reproduction let's try to see this particular uh test is in a in a in a broad scale now here is what is uh looking um in in looked when we are

00:35:43 taking a longitudinal section when you take a longitudinal section of this testes it it is having this small ductal appearance we call it seminiferous tibial seminiferous tubules and this seminiferous tubules is getting continued into what we call ready testes so this ready test is is continuing into another ductal area and this ductile area is called vas if ren sia so this vas efferencia is nothing but the continuation of ready testes towards another ductal appearance a rectal coil like area and that is called epididymis

00:36:37 so epididymis is nothing but the coiled structure just in continuation to the vas efrencia and this vas differentia is very important connectivity to the epitome structure now this epidermis is a huge coiled body and this body is having an upper head area we called it head of epidermis and then similarly we have a tail area we call it tail of epidermis and this epidermis is continue into another same duct system what we discussed which is called vas difference so vas difference is nothing but the

00:37:19 continuation of epididymis and this is what is communicating outside with the gland structure so this is going up and then communicating with the glass now just try to see that this whole thing is under a small seat like structure and we call that seat as scrotum and this is croton temperature is 2 to 2 to 2.5 degree centigrade lower as compared to the body temperature now this whole structure is what we have discussed in the longitudinal section now the the the test is as such completely is supplied with this

00:37:58 blood vessel which is called testicular artery testicular are tree so this testicular artery is giving blood supply to the testes so this is in in total uh about the the testis um is ductal system in the longitudinal section and in the next class we will try to discuss about this particular seminiferous tubule you