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Hello everyone this is an animated video on reaching the age of adolescence this video helped you to revise your concept in very quick time i recommend you to watch this video taking a pen notebook to prepare your own notes introduction the stage where human body starts transferring from childhood to sexual maturity is known as adolescence adolescence is the time
Period between childhood and adulthood adolescence is a time of change physical emotional mental and social in this chapter we will discuss about the changes associated with adolescence secondary sexual characters sex determination in human being and reproductive health objectives at the end of this lesson you’ll be able to recognize the changes associated
With adolescence know the hormones responsible for the secondary sexual characters understand the reproductive phase in females understand the process of sex determination in human beings realize the importance of reproductive health structural changes in the body male increase in height the boys begin their adolescent growth spurt at an average of about 10
Years and attains maximum at the age of 18. during periods of rapid growth the body needs extra nutrition both boys and girls need three balanced and nutritional meals a day and they need to eat healthy food voice change under the influence of androgens the voice box or larynx grows in both genders this growth is far more prominent in boys causing the male voice
To drop and deepen full adult page is attained at an average age of about 15 years when the larynx grows larger during puberty it sticks out at the front of the throat body and facial hair the appearance of hair in the areas of skin responds to action of androgens there is a large range in amount of body hair among adult men and significant differences in timing
And quantity of hair growth among different ethnic groups male musculature and body shape by the end of puberty adult men have heavier bones and nearly twice as much skeletal muscle some of the bone growth that is shoulder width and jaw is disproportionately greater resulting in noticeably different male and female skeletal shapes structural changes in female
Changes in height the girl begins her adolescent growth spurred at an average of about 10 years and grows at peak velocity at about 12 years attains adult height at about 16 years under arm axillary hair growth visible body odor and pimples rising levels of androgens can change the fatty acid composition of perspiration resulting in a more adult body odor as in
Girls another androgen effect is increased secretion of oil sebum from the skin and the resultant variable amounts of acne and pimples body shape fat distribution and body composition during this period also in response to rising levels of estrogen the lower half of the pelvis enlarges in size and thus hips widen providing a larger birth canal functional changes
In the organs puberty is initiated by hormone signals from the brain to the gonads the ovaries and testes in response the gonads produce a variety of hormones that stimulate the growth function or transformation of brain bones muscle skin breasts and reproductive organs the testes male sex organs start to produce sperms and the ovaries female sex organs enlarge in
Size and the eggs begin to mature in female puberty includes menstrual cycle secondary sexual characters the sudden change in the appearance of the body during the arrival of adolescence is known as secondary sexual characters some of the secondary sexual characters are appearance of voice change beards and mustaches in males an appearance of pimples increase in
Height and acne in females secondary sexual characters distinguish the males and females in a different way it is expressed in an adolescent during the onset of puberty expression of secondary sexual characters in males and females a characteristic such as breast development voice pitch or facial hair that distinguishes the sexes from each other the appearance of
These characteristics is influenced by the secretion of hormones hormones are the chemical substance secreted by the endocrine gland in males testosterone is the hormone initiating the secondary sexual characters estrogen is responsible for the production of secondary sexual characters in female testosterone is involved in greater bone density larger organ size
Higher muscle mass thicker hair growth wider shoulder bones and rib cage larger voice box thus deeper voice development of male sexual organs estrogen is involved in breast development development of female sexual organs increase in fat tissue particularly around the thighs hips and breasts reduced muscle mass wider pelvic bone growth of the uterine lining water
Retentions many of the characteristics which distinguish the male from the female in various species are simply the greater development of some structure or trait in one sex than in the other endocrine glands hormones and their functioning the endocrine system is an integrated system of small organs that involve the release of extracellular signaling chemical
Molecules known as hormones the endocrine system is instrumental in regulating metabolism growth development and puberty tissue function and also plays a part in determining mood some major endocrine glands are the pituitary thyroid and adrenal glands features of endocrine glands are in general their ductless nature their vascularity and usually the presence
Of intracellular vacuoles or granules storing their hormones sex hormones associated with the secondary sexual characters the gonads commonly called as the primary reproductive organs are the testes in the male and the ovaries in the female these organs are responsible for producing the sperm and ova but they also secrete hormones and are considered to be the
Endocrine glands testes male sex hormones as a group are called androgens the principle androgen is testosterone which is secreted by the testes production of testosterone begins during fetal development continues for a short time after birth nearly ceases during childhood and then resumes at puberty this steroid hormone is responsible for the growth and development
Of the male reproductive structures increased skeletal and muscular growth enlargement of the larynx accompanied by voice changes growth and distribution of body hair ovaries the groups of female sex hormones are produced in the ovaries the estrogens and progesterone these steroid hormones contribute to the development and function of the female reproductive
Organs and sex characteristics at the onset of puberty estrogens promote the development of the breasts distribution of fat evidenced in the hips legs and breast maturation of reproductive organs such as the uterus and vagina together progesterone and estrogens are responsible for the changes that occur in the uterus during the female menstrual cycle thyroid
Gland path of hormone produced by the endocrine to their target organ pancreatic gland the pancreas is both an endocrine gland producing several important hormones including insulin as well as an exocrine gland secreting pancreatic juice containing digestive enzymes that pass to the small intestine these enzymes help in the further breakdown of the carbohydrates
Protein and fat in the chyme adrenal gland the adrenal glands also known as suprarenal glands are the triangle-shaped endocrine glands that sit on top of the kidneys they’re chiefly responsible for regulating their stress response through the adrenaline hormones in other organisms metamorphosis is a biological process by which an animal physically develops
After birth or hatching involving a conspicuous and relatively abrupt change in the animal’s form or structure through cell growth and differentiation amphibian metamorphosis is the developmental process initiated by thyroid hormone which transforms a tadpole into a frog in several insect orders the adult looks entirely different from the lava that preceded it
This marked transformation is called metamorphosis metamorphosis takes place during a dormant stage called the pupa the sequence of development extends as larval pupil and adult stages during normal development of the domestic silkworm moth a hormone involved in the metamorphosis of silkworm moth is pro-thoracicotropic hormone ptth reproductive phases in females
The female reproductive system the female reproductive system consists of internal organs including the ovaries oviducts uterus and vagina external genital structures and the breasts menake the beginning of menstruation in females after puberty occurs at about age 15. in the reproductive phase of female life the menstrual cycle takes place between each menses the
Start of bleeding lasts about 28 days menopause occurs when the cycle eventually ceases between the ages of 45 and 55. sex determination in human being the sex of an individual is determined by the chromosomes a normal human being consists of 23 pairs of chromosomes among these 22 pairs are autosomes responsible for the expression of body characters and one pair
Of chromosome is sex chromosome which determines the sex of an individual person males consist of x y chromosome and females consist of x x chromosome as sex from a female parent who is having two x chromosomes physical requirements a balanced diet must contain carbohydrate protein fat vitamins mineral salts and fiber it must contain these things in the correct
Proportions summary let us summarize what we have learned the stage where human body starts transferring from childhood to sexual maturity is known as adolescence adolescent stage is a golden time in one’s life hence it is filled with full of fun and enjoyment puberty involves the physical changes that need to take place in your body to change your child’s like
Body into an adult body the boys begin their adolescent growth spurred at an average of about 10 years and attains maximum at the age of 18. when the larynx grows larger during puberty it sticks out at the front of the throat this is called as adam’s apple the girl begins her adolescent growth spurt at an average of about 10 years and grows at peak velocity at
About 12 years attains her adult height at about 16 years in males testosterone is the hormone initiating the secondary sexual characters estrogen is responsible for the production of secondary sexual characters in female the endocrine system is an integrated system of small organs that involve the release of extracellular signaling chemical molecules known
As hormones the gonads the primary reproductive organs are the testes in the male and the ovaries in the female male sex hormones as a group are called androgens two groups of female sex hormones are produced in the ovaries the estrogens and progesterone the pancreas is both an endocrine gland producing several important hormones including insulin as well as
An endocrine gland secreting pancreatic juice containing digestive enzymes that pass to the small intestine the adrenal glands are chiefly responsible for regulating the stress response through the adrenaline monarche the beginning of menstruation in females after puberty occurs at age about 15. in the reproductive phase of female life the menstrual cycle taken
Between each menses the start of bleeding lasts about 28 days menopause occurs when the cycle eventually ceases between the ages of 45 and 55.
Transcribed from video
Reaching the age of Adolescence | Science – Class 8th | Mrinal Debnath By Mrinal Debnath