Page 1 - 2.Lesson Notes-Changes at puberty-II
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SAI International School
                                             Subject- Biology Class-VIII
                                    Topic- Reaching the age of adolescence
                                          Subtopic- Changes at puberty-II
                                                       Module- 20
                                                     Lesson Notes

               3. Change in shape of body:When puberty sets in, rapid changes in body shape and
               appearance start in boys and girls.



                     In boys, the shoulders grow broad, chest becomes wider and muscles grow more
                       prominently.
                     Boys develop facial hair like moustache and beard.
                     In girls, the region below the waist becomes wide and development of breasts
                       takes place.



               4.Increased activity of sweat and sebaceous glands


                     The activity of sweat and sebaceous glands increases at the onset of puberty.
                     Children may even get pimples and acne due to increased activity of hormones
                       and glands in the skin.

                     Note:Exocrine gland –A few glands, such as, sweat glands, oil gland and salivary
                       glands, release their secretions through ducts.
                     Endocrine gland –Some glands release hormones directly into the bloodstream.
                       So, they are also termed ductless glands.For example, pituitary, thyroid etc.



               5.Development of sex organs


                     In boys, testes and penis becomes completely developed.
                     The testes become capable to produce sperms and male sex hormones
                       (testosterone).
                     In girls, the ovaries develop and release eggs / ova.
                     Ovary also releases female sex hormones (estrogen and progesterone).


               6.Reaching Mental, Intellectual and Emotional maturity


                     During puberty, mental, intellectual and emotional development takes place in
                       boys and girls.
                     They become more independent, self conscious and their way of thinking
                       changes.
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