Human Growth (1962)

don't bother George you're almost finished with that report George yeah just about he's reading about Indian voice adolescent like him why don't you grow up grow up I'm just as grown up as you are even if you are older says who Mrs Baker she said that girls than boys I suppose if she said you were a genius you'd believe I would I think person and a very good teacher all the kids at school like her something for my report oh what's that only the grown people have clothes on say Mom can I wear skirt tomorrow yes Josie I've almost finished Heming it until they your clothes at all the wear skirts was considered a sign of sexual maturity that's interesting George and it ties in with the film Josie was telling us about sure does we saw that film last year I'm on the preview committee dad I'm going to tell the class what to look for in the film well have you decided what you're going to say I'm going to tell them that the most important things to look for are the changes that take place in our bodies and feelings when we grow up grow up that is when we become adolescents we've used that word adolescent before who can tell us what it means Dorothy well it's boys and girls just beginning to mature it happens when they're about our age that's right Dorothy are there any other points from the preview committee yes Mrs Baker Warren has a list of questions we'd like to project for the class to see that's good go right ahead Warren John would you put out the front lights please when does human growth begin how much does one grow before birth do boys and girls grow at the same rate what are the main growth changes that occur during childhood and Adolescence the committee did very well the film we'll see this morning will give the answers to these questions it will also show the earliest phases of growth as well as the change changes that take place during childhood and Adolescence it will help you to understand the way the cycle of human growth is repeated over and over from generation to generation and now we're ready for the film lights when we talk about growth we usually think of growing up but the long road of growth is not just up if it were it would mean that this little baby would someday look like this now let's see how human beings really grow here are two average babies a little boy and a little girl in the course of a few years they will reach maturity during the first 3 years growth is very rapid the boy and girl become twice as tall and five times as heavy as they were at Birth by the age of six they have added still more height and weight notice that the boy is a little bigger than the girl at 9 arms legs and Trunks have become long and slender giving the body a slim appearance at about this age the girl grows more rapidly than the boy by 12 or 13 the average girl is taller and heavier than the boy and she looks more mature at 15 the girl's growth slows down while usually the boy keeps on growing rapidly for another year or two when they reach their late teens or early 20s they are fully mature people with the boy again being appreciably larger than the Girl by comparing the adult with the child we can see the growth change notice that the adult face and head are less round and the arms legs and trunk relatively longer the boy's shoulders are Broad and his body muscular while the girl's body is more curved as well growth is controlled by tiny organs called glands within our bodies one of the most important of these is the pituitary gland located in the head it secretes chemicals into our blood the chemicals are called hormones and they regulate body growth the pituitary hormone influences the secretions of other glands notably the testes and ovaries located in the pelvic region of the body the testes secrete the male sex hormone and the ovaries the female sex hormone presence of these hormones in the blood brings about many changes in the bodies of both boys and girls and in the way they feel and act too for boys hair begins to grow on the face for both boys and girls hair grows under the arms in the pubic region and Elsewhere on the body the breasts of the girl begin to develop the vocal cords of both boys and girls get larger and their voices deepen these physical changes make the boy feel more manly and the girl more womanly both feel independent they begin to be interested in members of the other sex in social activities and in being together these are normal feelings in addition to hormones the testes and ovaries produce the male and female sex cells from which we all have our beginning the male cell or sperm cell is so small it can be seen only with a microscope when we magnify the sperm cell many times we see the head containing the nucleus and the tail that Wiggles and causes the cell to move the female cell or ovam while larger than the sperm is still no bigger than a pinpoint by enlarging the ovam many times we can see the cell wall and the dislike nucleus when the sperm from the father unites with the ovam from the mother growth Begins the nucleus of each sex cell contains the genes and chromosomes which determine the heredity of the child his resemblance to his parents and other characteristics when a boy is between the ages of 13 and 16 the testes begin to produce sperm cells these sperm cells are carried through the tubes in a thick colorless liquid called seen and at certain times are expelled through the penis this happens during mating and sometimes during dreams in sleep this is a normal function of the body in addition to the ovaries the sex organs of the girl consist of the tubes the uterus and the vagina when a girl is between the ages of 12 and 15 the ovaries begin to produce OVA or egg cells about once every month an ovam ripens and leaves the ovary moving into the tube while the ovam moves slowly along the tube the uterus becomes richly supplied with blood to nourish the egg but if the ovam doesn't meet a sperm cell it fails to grow and is discharged some days later the uterus sheds its lining and a little blood passes from the body the bleeding decreases and in a few days stops completely this process is called menstruation the whole cycle begins again with another ovam ripening usually in the opposite ovary during early adoles the menstrual cycle may be quite irregular it usually takes a year or two for a rhythm to become established these functions begin as we attain sexual maturity but all of us do not mature at the same age these boys and girls for example are all 13 years old yet among them we see many different differences in size and maturity these differences and the fact that girls usually mature earlier than boys both physically and emotionally sometimes create problems but by the time boys and girls reach their late teens these problems will have been solved also by the time they have completed their education have steady jobs want to get married and are ready to accept the responsibility of having and raising children the differences in sexual maturity will have disappeared human growth can begin only when the sperm cells of the father during mating pass from the penis into the vagina of the mother the sperm cells use their threadlike tails to move into the uterus and tubes if the sperm cells meet an ovam and one sperm succeeds in breaking through the cell wall fertilization occurs the nucleus of the sperm joins with the nucleus of the ovam and growth Begins the fertilized ovam begins to divide into many cells while moving along the tube to the uterus there it attaches itself to the inner lining drawing its nourishment from the blood of the mother it continues to grow and in a month looks like this at 2 months it is much bigger and is already beginning to look like a baby you can see the cord which connects the baby to the mother and through which the baby receives its nourishment and oxygen the uterus which is normally not much bigger than a fist is muscular and elastic enough to expand to many times its normal size at 4 months you can already see why this expansion is necessary the baby now has arms and legs that move inside the mother by 6 months the baby has gradually turned to this head down position in preparation for birth the baby is very active now it is not only the uterus that expands to accommodate the growing baby here you can see how the whole abdominal wall stretches this baby has developed for 9 months and is about to be born if the mother were lying down this would be the position of the baby just before birth you can see the mother's spine below the enlarged uterus the head settles to a lower position and the muscles of the uterus begin to force the baby out the muscle walls of the vagina expand to make room and the baby's head begins to move out of the mother the doctor lends a helping hand and the new baby meets the outside world since the baby no longer has to depend upon its mother's blood for food and oxygen the doctor ties and cuts the cord the baby cannot feel the cutting any more than you can feel it when the barber Cuts your hair growth continues and this baby will become a full-grown boy or girl and eventually a father or a mother thus continuing the cycle of human growth lights please the principles of growth and development we've seen in this film apply to all human beings now let's begin our discussion by answering the first question from the preview committee who can tell us when human growth begins Bill growth begins when a sperm cell enters an egg cell suppose the sperm cell doesn't enter the egg cell then the egg isn't fertilized and it dies in a few days that's correct Bill Steve do you have a question well it's sort of a silly question but I was wondering why there's so many sperm cells and only one egg cell that's a very good question Steve let's use the projector to explain it now in the first place remember that the male sperm cell are being produced all the time while only one egg cell is produced each month that's one reason there are so many more sperm cells than egg cells then see what would happen if there were only one or a few sperm cells the ovam is produced here and moves into the tube the sperm cell has to travel all the way up here to find the ovam and if there weren't so many of them the chances of the OV meeting a sperm cell would be small lights please does that answer your question Steve yes Mrs bigger I bet other questions Julie about menstruation is it really normal for the body to bleed like that completely normal Julie remember in the animated film the lining of the uterus became filled with blood with which to nourish the fertilized ovam well when the ovam is not fertilized there's no need for this nourishment so the uterus merely sheds its in a lining and naturally a little blood leaves the body at the same time oh I see now for the questions the rest of you have Carolyn do boys have anything like menstruation I heard my mother tell a neighbor I was born cesarian what does that mean why don't all people have bread hair what happens if more than one sperm cell enters an egg how long will it take till my voice changes are girls always bigger than boys at 12 or 13 why do some kids grow faster than others I'd like to know more about different kinds of hormones everybody says I look like my Aunt Sarah why do I have to look like her when I don't even like [Music] her all of those are excellent questions you students who've been watching this film you've heard the questions we're going to discuss you can discuss these same questions with your teacher and you can ask any others you have in mind