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Current time:0:00Total duration:6:38

Video transcript

welcome to the reproductive system so let's start by asking what is the reproductive system it's basically a system in our bodies that includes our sex organs and certain parts of our brain you can see the sex organs here on the male and here in two places on the female so this system within our bodies allows us to reproduce it allows us to make babies and to make babies what we're doing is combining genetic material from a biological mother's egg and a biological father sperm to make our offspring and we typically do this via sexual intercourse so let's first take a brief look at a couple of the most important sex organs that males and females have in their reproductive systems so the males have the testes and these are the most important structures sort of the structures that everything else is built around an in in a male and that's because the testes actually produce his contribution to a baby they make these small mobile cells that carry his genetic material into a female to fuse with her genetic material to cause a pregnancy and these small mobile cells are his sperm another important male organ of the penis and the penis is used to deliver his sperm inside the female mate to increase the chance that it meets her egg so those are really the major male organs now on the female side one of her major organs is the ovary and she has two just like just like how males have two testes and in fact the ovaries and testes are homologous they came from the same precursor in development now the ovaries responsible for producing the female's genetic contribution to a baby that is the egg the ovaries though are a lot different to the testes in that the testes are constantly producing lots and lots of sperm to the tune of millions per day whereas the ovaries only release one egg per month so the next really important female organ is called the uterus and the uterus is basically a really thick muscular organ that's capable of stretching out and and it's actually where the baby's developing during pregnancy until birth the next really important female structures are the breasts and the breasts are important because they produce milk during pregnancy see and afterwards via a process called lactation and lactation happens due to a series of hormones that generally get released around pregnancy so this breast milk that gets produced can can feed and nourish the growing baby and it actually plays a role in creating a stronger immune system for the baby so we've seen some of the major structures of both male and female reproductive systems but is that all the reproductive systems are actually know besides producing the sperm and egg the reproductive systems produce chemicals whose signals have a really strong influence over activities in our bodies we call these chemicals hormones and because they come from our reproductive systems we refer to them as our sex hormones for example the male's major sex hormone testosterone which is actually produced in the testes is responsible for many masculine traits such as body hair the deepening of your voice muscle growth and there's possibly even a link to levels of aggression in males on the female side of things the ovary is the primary producer of some major female hormones like estrogen and progesterone estrogen and progesterone play a major role in the timing of egg release from the ovaries estrogen is also responsible for the development of a lot of feminine traits for example breast development so there's the making of the sperm and the egg there's the production of the major sex hormones what else does a reproductive system do well it does one more really important thing and that's coordinate the meeting of the sperm and the egg and it does that by the male's penis and the female's vagina these two organs are used to ensure that the sperm and the egg meet each other so the penis actually deposits sperm within the vagina so that sperm is a better chance of reaching and and fertilizing the egg released inside her reproductive tract so you might be thinking does the reproductive system do all this stuff on its own I mean what tells it what to do and that's a good question the reproductive system is actually controlled by the braids there's an area in the brain called the hypothalamus that sits just about there on the inside brain just about in the middle and the hypothalamus actually releases a hormone called gonadotropin-releasing hormone or GnRH GnRH affects another part of the brain called the anterior pituitary which fits right about there just under the hypothalamus and the anterior pituitary in response to gnrh releases two hormones luteinizing hormone or LH and follicle stimulating hormone or FSH and it's the luteinizing hormone and the follicle stimulating hormone that primarily affects the male and female sex organs so the male's testes and the female's ovaries to control their functions finally a word on pregnancy as pregnancies a huge part of reproduction and certainly the most long-lasting part so pregnancy results when a sperm successfully fertilizes an egg to create a zygote a zygote is a first cell in a new organism that has genetic material from both mom and dad and that genetic material has come from the sperm and the egg that have fused the zygote goes through a series of developments and eventually implants itself within the inner wall of a woman's uterus to grow so that's in here remember that thick muscular organ we talked about the third step is what we'll really broadly call gestation gestation is basically the development of the fetus into a baby so the development of all the fetuses organ systems including their brain spinal cord lungs cardiovascular system their reproductive system all the systems in their body gestation readies the developing infant to be born and it takes about nine months when the baby's ready to come out of the uterus and into the world a number of hormonal changes take place in the mother's body this signals her to start getting ready to push the baby out of her body in other words give birth to the baby she then goes through a process called labor also known as partition to give birth to the baby after the baby's born the last step is to give him or her a name
Biology is brought to you with support from the Amgen Foundation