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Reaching The Age Of Adolescence

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Science

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Science

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CBSE Gujarat Board Haryana Board

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Class 10 Class 12

How does water effect the production of thyroxine in frogs?


The production of thyroxine requires the presence of iodine in water. If iodine is not preent insufficient amount in water. thyroxine is not secreted in the frogs. Since thyroxine is required for metamorphosis, inadequate amount of thyroxine hampers metamorphosis. Thus, the tadpole cannot trasform into adult frogs require thyroxin for the process of metamorphosis. 


What is the term used for secretions of endocrine glands responsible for changes taking place in the body?


Hormones.


What is menstruation? Explain.


Menstruation is the bleeding in women because of the shedding of the thick lining of the uterus. the walls of the uterus shed when the fertilization does not take place. Menstruation occurs once in about 28 to 30 days.




List the changes in the body that take place at puberty.


The changes that take place in the body at age of puberty are:

(i) Increase in height.

(iii) Change in body shape..

(iv) Change in voice.

(v) Incresed activity of sweat and sebaceous gland.

(vi) Development of sex orgnans.

(vii) Development of secondary sexual charater like fascial hair in boys and breasts in females.

(viii) Attaining the mental, intellectual and emotional stability.


Define adolescence.


Adolescence is the period of life, when the body undergoes changes, leading to reproductive maturity. It begins around the age of 11 and lasts upto 18 or 19 years of age. In girls adolescence may begin one or two year earlier than boys.


Prepare a Table having two columns depicting names of endocrine glands and hormones secreted by them.


Endocrine Organs

Hormones Secreted

(i) Thyroid

(ii) Pancreas

(iii) Adrenal glands

(iv) Pituitary gland

(v) Testes

(vi) Ovaries

(i) Thyroxine

(ii) Insulin

(iii) Adrenalin

(iv) Growth hormones

(v) Testosterone

(vi) Estrogen