Your Body During Adolescence (1955)

[Music] this class is getting ready to have their photograph taken for the high school yearbook nothing unusual about them they're much like you like any group of boys and girls 13 to 15 years old hold still please don't move thank you here it is 17 young people some tall some short some fat some Thin some strong and some not so strong however all have one thing in common they all are adolescent young people in the process of changing from child to adult this stage of development during which the physical changes from child to adult occur is called puberty puberty usually begins at an earlier age in girls than in boys most girls enter puberty at about 12 or 13 and most boys at about 14 or 15 puberty is a very important stage in your lives and you should fully understand what it means and how it affects your body these simplified drawings represent the bodies of a growing boy and girl before the onset of puberty regulating the growth and life of the human body is a system of glands they are called the endocrine or ductless glands these glands do their work by creating certain chemical substances called hormones some of these hormones bring about changes within the body during puberty they are also responsible for the changes which finally turn a boy into a man and a girl into a woman these glands are the pituitary gland the thyroid the parathyroids the adrenals the pancreas and the sex glands the glands thought to be most important in the development of the human body during puberty are the pituitary gland and the sex glands the pituitary gland sets off the process of puberty by increasing the secretion of that hormone which controls the rate of of growth of the body therefore puberty is introduced by a rapid Spurt of growth growth however varies for each individual person for some the young body may start its growth by shooting up several inches in a few months for others the growth in width may come first and there's even another kind of person the body may take its own good time before it starts growing in any direction however the proportions of the body usually become balanced when the process of puberty is completed sometime after the period of rapid growth is started the pituitary gland for the first time secretes another kind of hormone this new hormone influences the sex glands in both sexes in the male the sex glands are called testes in the female ovaries the sex gland now increase their own production of hormones with the result that the physical differences between boys and girls become more pronounced in the boy the larynx and the vocal cords change so that his voice acquires the deeper pitch of a man's voice the shoulders become broader the thighs grow longer and the muscles become stronger hair begins to grow on the face under the arms and in the pubic area perspiration also increases the girls also change the hips broaden out the thighs and shoulders become rounded the pubic hair and underarm hair begin to grow and the breasts begin to develop sometimes one breast will mature more rapidly than the other this occurs quite often and is no cause for concern but these developments of puberty do not always happen at the same age it is perfectly normal that some boys and girls develop sooner others later therefore whether you're among the early or the late ones don't let it bother you also for some boys pubic ha may be the first sign of puberty in others the change of voice and for some girls the development of breasts May indicate the beginning of puberty while in others this may be the last development to occur in addition to these developments another change occurs at puberty the sexual apparatus begins its full development in the male the external reproductive organs consist of the penis and the scrotum the scrotum contains the testes the testes as you recall are the sex glands in the male they're like a factory in which beginning at puberty the male sex cells are made these sex cells are called spermatozoa or sperm cells for the next 30 or 40 years or even longer of the male life these sperm cells are constantly being formed in the testes they are stored in a long tube that is folded to fit within the scrotum millions of sperm cells are stored in this tube from which some of them may be discharged from time to time during sleep from this Reservoir the sperm cells travel through the seminal ducts here fluids from various glands are added to form the semen the semen containing the sperm cells passes through the urethra sometimes called the urethal canal and out of the penis the Sean in the last part of its Journey travels the same route taken by the urine coming from the bladder now let's consider the female reproductive organs seen from the outside they consist of several fos of skin called AIA unlike the male the sex glands of the female the ovaries are located well within the body at puberty the ovaries began to discharge eggs these eggs called OVA are the female sex cells and they continue to be discharged for the next 30 years or so many eggs grow in the ovaries but usually only one matures about every 28 days when an egg matures it breaks through the wall of the ovary and enters this tube the fallopian tube this breaking through of the egg is called ovulation the mature egg travels slowly through the fallopian tube toward the uterus at the same time the lining of the walls of the uterus becomes enriched with blood if sperm cells from a male have been introduced into the vagina they must travel up through the uterus and into the fallopian tubes it is in the Fallopian tubes of the female that fertilization usually takes place fertilization is the process whereby a single male sperm combines with a female egg to produce a new human life the fertilized egg then moves on and attaches itself to the walls of the uterus the baby is developing in the uterus of the mother food from the blood in the wall lining of the uterus feeds the growing baby until it is fully developed within the mother there is no direct connection between between the blood of the mother and the blood of the baby the time during which this development occurs lasts 9 months and is called pregnancy after this the baby is born if fertilization of the egg does not occur the egg dissolves or disappears when this happens the blood in the wall lining of the uterus is not needed and is discharged from the body this is called menstruation it happens every time an unfertilized egg dissolves away that is about every 28 days so we have seen that during adolescence our bodies undergo some intricate and wonderful changes as a result of these changes boys and girls become men and women bigger stronger and capable of having children of Their Own adolescence is the time of transition from childhood to adulthood giving you the Privileges as well as the responsibilities of a mature human [Music] being [Music]