WBBSE Notes For Class 8 General Science And Environment Chapter 9 Endocrine System And Adolescence

Chapter 9 Endocrine System And Adolescence

Have you noticed yourself and your friends and relatives of your age or one or two years elder in school, family and neighbourhood? After a few days of observation, you will notice some behavioural, physical and mental changes of these people.

If you note down the changes then you will find some physical changes like increasing height, and weight, change of voice [harsh voice (in boys) or shrill in girls] appearance of a thin line of moustache in boys and breast development and the onset of the menstrual cycle in girls, also a change of smoothness of the skin.

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You will also find some behavioural changes among your classmates too. They are more aggressive and try to establish himself or themselves in every event happening around them, getting angry, feeling jealous, feeling offended. Girls will also experience some physiological changes like the onset of the menstrual cycle.

“WBBSE Class 8 General Science Chapter 9 notes, Endocrine System and Adolescence”

Around us you may notice some short-height (dwarf) and long or very long-height (gigantic) person. If you go to a tea stall you will see some people are asking for tea without sugar and someone taking tea with sugar.

All these events mentioned above are controlled by some chemical substance of the body. This chemical substance is known as a hormone and the system that controls all these are known as the Endocrine system.

Your observation (in two-six months intervals)

Sex Male/ Female	Age	Height	Weight	Change of nature of behaviour
1
2
3

 

1.  The term hormone is derived from the Greek word “hormone” which means ‘to urge on’ or “to set in motion”
2. Hormone’ the term coined by W. Bayliss and E. Starling, in 1905.

Chapter 9 Endocrine System And Adolescence Hormone

Hormone

The hormone is a chemical substance secreted by the endocrine glands (ductless glands) transported through blood (in most of animals) to the site of action, the target cell or organ and regulates the biological processes in the organism and destroys after a function.

1. Different changes in our mind and body occur from our birth to the end of our life. Hormones control these changes in our bodies. Thus hormones play a vital role in our bodies. Hormones play an important role to control our emotional feelings such as feeling good, feeling depressed, angry, crying, smiling etc.
2. Hormones are produced in our body according to need sometime within seconds and are destroyed after completion of work. However, some hormones remain in the blood throughout our life.

Properties of hormone

1. Hormones are made up of proteins.
2. Hormones are effective in very low concentrations.
3. Hormones do not provide energy or building materials but they do have effects on the growth, differentiation and metabolic activities of their target cells or organs.
4. Hormones are transported from their origin (endocrine or ductless gland) to the target place through blood (except local hormones) and destroyed after completion of work.
5. Excess or deficiency of hormones leads to disorder.
6. The hormone is called a chemical messenger because as a chemical substance that it carries. the message of coordination or activities.
7. Both hormonal and nervous systems control and coordinate the body’s functions and work in coordination to maintain a steady state condition (called homeostasis).

Chapter 9 Endocrine System And Adolescence Co-Ordination

Co-Ordination

Coordination is the working together of various organs of the body in a proper manner to stimuli. In our body, two types of coordination occur. One control by. nervous system (Physical coordinator) and other by the endocrine system. When mosquitoes or any other insect-like cockroaches etc.

come contract with our skin through merve brain receives the signal and then brain reacts.—Order the hand to remove them. This is an example of nervous coordination.

The endocrine system is a chemical coordination system in the body. It comprises endocrine glands, their hormones and their mode of action. It is directly or indirectly under the control of the nervous system. Therefore, the nervous system and endocrine system are often collectively called on neuroendocrine systems.

“Class 8 WBBSE General Science Chapter 9 notes, Endocrine System study material”

After getting the necessary order the hormone is produced in its proper position (endocrine glands) and reaches to the target organ via blood or body fluid. The target here is called the receptor. Hormones in most cases start their work slowly but its effect persists for a long time.

Hormone 4 is destroyed after the completion of work excess or deficiency of hormone levels in the blood or particular parts of the body lead to many disorders.

The human body possesses different types of glands.

The gland is a cell or a group of cells which secret or release specific substances such as endocrine glands secrete hormones, and digestive glands secrete enzymes.

Glands in our body are of two types-

1. Endocrine glands and
2. Exocrine glands.

Exocrine glands have ducts and endocrine glands are ductless.

1. Endocrine glands:

Glands which have no ducts (ductless) and pass their secretion into the surrounding blood for transport to the site of action e.g. pituitary gland, thyroid gland etc.

2. Exocrine glands :

Glands which have ducts and release secretion out through ducts, for example, the Salivary gland, Sweat glands. ‘

There are some glands which are both endocrine and exocrine in nature, these glands are called mixed glands. Such as the pancreas secrets enzymes present in pancreatic juice through ducts and the endocrine because they secrete some other hormones directly into the bloodstream.

1.  The pituitary gland is known as the master endocrine gland as because it controls the activities of other endocrine glands.
2.  Hypothalamus is called the ‘master of master gland’.

Chapter 9 Endocrine System And Adolescence Main Endocrine Glands Of Humans and Their Functions

1. Pituitary gland :

It is a small two-lobed gland found in the base (hypothalamus) of the brain (forebrain). The upper and lower part of the gland is known as the Anterior pituitary and posterior pituitary respectively.

A hormone secreted from Anterior Pituitary glands are –

1.  Somato trophic hormone (STH) – stimulates the growth of the body.
2. Thyroid-stimulating hormone-(TSH)- stimulates the activity of the thyroid gland and secretion from it.
3. Adrenocorticotrophic hormone – (ACTH) – stimulate the production and secretion of hormone secreted from the adrenal cortex.
4. Gonadotrophic hormone – (GTH) – control the production of sex hormones from the ovary and testis. Besides these vasopressin or Antidiuretic hormone (ADH), Oxytocin are secreted from the posterior pituitary.Hyposecretion of STH in childhood cause Dwarfism (3 ft height) and Hypersecretion of STH in childhood causes Gigantisms (7-8 ft. height) and Acromegaly (Gorila-like height and elongated jaw).

Chapter 9 Endocrine System And Adolescence Thyroid

Thyroid

It is the largest endocrine glands human body. It lies below the larynx on each side and anterior to the trachea. It also has two lobbed glands. The hormone secretes from this gland is Thyroxine. Iodine is needed for the formation of this hormone.

Thyroxine regulates the basal metabolic rate (BMR) and calcium balance of the body. It Enlarged thyroid gland controls the respiration rate and energy production of cells, increases heart rate, also helps in growth by increasing muscle and bone and also develops mental faculties.

 

Hyperthyroidism-

It is the condition caused due to high secretion of thyroxine and leads to theJSraves’ disease or an exophthalmic goitre (enlarged eyes), enlargement of the thyroid gland which may cause a bulge in the neck (goitre). You may see it in some people’s necks.

Hypothyroidism:

It is caused due to decreased secretion of thyroxine and leads to the diseases-Critinism retardation of physical and mental development in infants and children.

Criticism-

Is a condition produced in infants and children where retardation of physical and mental development occurs? The abdomen becomes swollen, the tongue hangs out.

Goitre enlargement of the thyroid gland— causes when the dietary Iodine intake falls below normal, and thyroid hormone synthesis is inadequate. Myxedema (= Gull’s disease) developed in middle-aged persons. Symptoms loss of energy and appetite, weight gain, mental dullness and dry, puffy skin

Chapter 9 Endocrine System And Adolescence Pancreatic Gland

Pancreatic Gland

This gland is a mixed gland which are partly endocrine and partly exocrine in function.

location Of Pancreatic Gland :

It is the second largest gland in the body located below the stomach in the loop (V turn) of the duodenum. Endocrine [Darts of the pancreas is called islets of Langerhans [discovered by Langerhans (1869)] Main hormone secret from isolates of Langerhans of the pancreas is insulin, (This gland also secrets glucagon and somatostatin hormone).

1. Insulin performs an important function in body—it enables the liver and muscles to store glucose as glycogen (glycogenesis).
2. Insulin lowers the blood glucose level. It helps glucose to enter into the cell from the blood.
3. It reduces the breakdown of proteins and fats in the body. Insulin is called an anti-diabetic hormone.
4. Hypo-secretion of insulin causes the disorder of the body ceÿs °f >slets °f Langerhans of known as diabetes mellitus (Hyperglycemia).

Insulin is secreted from the Beta cells of islets of Langerhans of the pancreas. In diabetes Mellitus beta cells (\)) of Islets of Langerhans are unable to produce adequate Insulin, ns a result the movement of glucose ‘ from blood to the cell is hampered, Some of the glucose Is excreted In the urine, as well as loss ‘ of water also caused due to excessive urination. This causes excessive thirst (it s one of the symptoms of this disorder).

A common symptoms of diabetes Mellitus-

1. Weakness
2. The healing power of any cut delayed
3. Excessive thirst
4. Excessive urination.

In diabetes, a Mellitus person becomes very weak. The functional power of the kidneys, heart and eyes is reduced.

Chapter 9 Endocrine System And Adolescence Adrenal Gland

Adrenal Gland

Adrenal glands (= supra renal gland) are paired triangular glands present on the top (upper part) of the kidney, Adrenal glands look like caps set on the kidney, v Adrenal has two distinct parts Adrenal cortex and the Adrenal medulla.

Adrenaline (= epinephrine)hormone is secreted from the Adrenal medulla. Adrenaline helps to combat different emergency situations. So this hormone is termed as an emergency hormone.

Important functions of Adrenaline are

1. Increase respiratory rate, heart rate, and pulse rate
2. Body temperature, blood pressure
3. Adrenalin provides energy for work.

Heartbeat—

Pulsation of the heart including one complete systole and diastole. Contraction of the heart is known as systole and expansion of the heart is known as diastole. It controls urine production. It also controls different mental conditions like fear, conflict, anger etc. Increases respiratory rate.

Hypersecretion of adrenaline the face becomes rounded and swollen this is known as Moon’s face. The skin of the face becomes rougher and more pale. Due to hypo secretion the healing of wounds, hypo delayed, poor digestion and weakness in the muscle.

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In general, adrenaline prepares the body to face emergency conditions of physical and emotional stress, like a fall in blood pressure, muscular exertion, pain, cold, injury, anger, fear tension etc. So this hormone is called an Emergency hormone. The adrenaline hormone is known as the fight or flight response hormone.

Chapter 9 Endocrine System And Adolescence Reproductive Glands

Gonads-

The gonads are the sex glands of the body such as the ovary and testis these reproductive glands ovary and testis produce ova and sperms respectively. These glands also secret hormones. Estrogen, progesterone and testosterone are called sex hormones. These hormones became active after a specific age in males and females.

Ovary :

Present in the female body. The important hormones secret from the ovary are oestrogen and progesterone.

Testis :

The reproductive gland is present in males. The important hormone secreted from the testis is Testosterone.

The function of Oestrogen :

Helps to develop the female body and the normal functioning of female secondary sex organs such as the uterus, vagina etc,

1. Regulate female sexual behaviour.
2. Control the development of female secondary characteristics- like breast enlargement, broadening of the pelvis, and control menstrual cycle.
3. Oestrogen helps deposit fat below the skin.

Chapter 9 Endocrine System And Adolescence Testosterone

Testosterone

This male hormone is secret from Testis. During adolescence testosterone is more active, the appearance of a moustache and beard, change of voice, development of muscles, and strengthening of bones all are due to the testosterone hormone. Testosterone stimulates the formation of sperm.

1. Testosterone secretes from interstitial cells of Leydig (Leydig cells) of the testis.
2. Testosterone stimulates the growth and development of male secondary sex organs and secondary sexual characters.

Oestrogen is also found in the male body as well as testosterone is also found in the female body but both are in lesser amounts. Progesterone stimulates and regulates various body functions in females such as ovulation (release of egg from an ovary) and plays a major role in maintaining pregnancy.

Adrenaline is a hormone secreted by the adrenal medulla during stress. This is called as an emergency hormone because it initiates a quick reaction which makes the individual to think and respond quickly to the stress. The hormone increases metabolic rate.

Observe your locality and note down the symptoms of the hormonal disorder and make a table

Symptoms	Responsible hormone
1.    Very short height (dwarf)
2.    Unusual growth of body and bones
3.    Rounded moon-like face thickening of the skin
4.    Weakness, excessive urination, healing power delayed
5.    Swelling of glands around the neck.

 

Chapter 9 Endocrine System And Adolescence Adolescence

Adolescence

It is one of the most important phases in human life. Several changes occur during this phase. Adolescence is the period between childhood and adulthood. This phase is commonly known as ‘teenage’. According to the World Health Organization (WHO), adolescence is the phase between 10 to 19 years of age. Rapid changes occur in the body and mind during this phase.

You also may notice changes in your body. During this phase you may have seen changes of physical structure such as weight, height, and complexion, you may also seen mental and behavioural changes. Endocrine glands and hormone secretion from them play a vital role in bringing about these changes.

During this phase of development adolescents begin to transition from childhood to adulthood. Eating disorders, mood-changing disorders, aggressiveness etc are usually occurrences. It is characterized by rapid physiological changes and psychosocial maturation.

Adolescence is also the stage when young people extend their relationships beyond parents and family and are intensely influenced by their peers and the outside world in general. This is a period of active growth and development of physical, sexual, social and emotional.

“WBBSE Class 8 Endocrine System and Adolescence notes, General Science Chapter 9”

During this phase problems in growth and hormonal balance may occur. Height may be short or tall, irregularities in the menstrual cycle, obesity and the appearance of acne are common among adolescent girls and boys. Besides physical changes, emotional changes also occur during this phase.

Chapter 9 Endocrine System And Adolescence Psychological Changes In The Adolescent Period

Overjoyed, enthusiasm, togetherness, some sort of aggressiveness, eagerness to make a relationship, feel attraction to the opposite sex and others. Hormones play an important role. Hormones are capable of making a person more emotional and sensitive than usual. Teenage body not capable to cope with sudden changes so teenagers show some.

very odd behaviour and reactions. For elderly persons of the family, teachers and parents should be soft and keep in touch wit t e teenage boys and girls and should explain why these are happening such as the appearance of a pimp, swings of moods, anger, and aggressiveness are common to all.

All of them have crossed these stag During this phase teenage boys and girls compare themselves and if not he or she thinks up the mark he or she feels depressed. But adolescent boys and girls should remember that all individuals are beautiful in his/h own way. All of them have something to its own and can impress others.

Pimples and some other physical problems would be solved if they maintain proper hugs and exercise.

Emotion management-

Teenagers are more emotional. They feel happy after listening to (hearing) good songs and seeing movies. They show their joyfulness when their favourite team win and are morose at their defeat, they get angry and depressed to hear their criticisms.

 

 

Tears come to my eyes very often to hear the misfortune of others. All these are normal behaviour. But an uncontrolled expression of happiness, anger or sorrow affects our physical and mental health. Some uncontrolled expressions such as continuous playing horns of car and explosion of crackers without interruption after winning a game or vote.

Ranshake of car, shops in aggression. We need to control our emotions. We need to understand our feelings before expressing ourselves. We must understand our uncontrolled emotions and feeling that can damage others’ happiness. Therefore, we need to understand these things.

Teenagers must try to control their emotions and feeling. But if we suppress all these emotions in their mind then it will affect their mind and health. So it is needed to sublimate of emotions through other things like play, cultural programmes, deleting programmes etc.

Chapter 9 Endocrine System And Adolescence Lists Of Some Feelings And Emotions

1.  Fear
2.  Anger
3. Crying
4. Depression
5. Happiness
6. Sorrow
7. Satisfaction
8. Offended
9. Grievance etc.

expression of some feelings are

1. Sweating of palms
2. Choking of voice
3. Muscle cramps
4.  Headache
5. Trembling of hands and limbs.

If the boys and girls who are passing the adolescence stages remember that

I am a good child of my parents because I love them they love me they have faith on me and I will be able to do something good for them in a different way. I want to see them happy.

1. There are so many ways to be happy so I should not morose in one or two incidents.
2. I am a good friend because I feel his or her feeling, I can stand by him/her and in a difficult situation as well as his/her good condition.
3.  I can take some responsibility, I have confidence if I fail in one or two occasions I would not depressed. I have the power in myself that I will recover it. Everyone does not get success in every case there are lot of stories of failure of great and successful people in the world.
4. My special ability is—it may be a good artist, good player, good organizer, good cook or other skill.
5. I am loved by many people if one or two or a few may not love me but there are lot of people who love me, in the classroom, in my local area or in other places all my parents and kith and kin. ‘
6. I am a good student in class because I never try to ignore or violate school rules. Rules in any place are good for society. If I am given some light punishment I should understand why this or that was given to me. Hope you will get the reason.
7.  Doing something in a group or togetherness is good but before doing this I should analyse whether it is good or not and should control of my emotions before doing this.

Chapter 9 Endocrine System And Adolescence Adolescence And Life Skill Education

Life skill education is a special behaviour which helps us to face various needs and challenges and try to control our emotions. During teenage or adolescence rapid changes occur. To cope with these changes we need to acquire life skill education to face the pressure of uncertainty of the environment and the challenge.

According to WHO—

Life skill—The abilities for adaptive and positive behaviour that enable individuals to deal effectively with the demands and challenges of every day.

 

 

According to WHO recommendation life skill education are as follows-

1. Self-awareness-

We need to identify our own liking and disliking successes and failures and learn to control them according to the situation.

2. Critical thinking-

After facing various, problems, solving them after proper analysis and changing behaviour accordingly. We also have to learn this.

What is Life skills? As recommended by UNICEF

Life skills-based education is a behaviour change or behaviour development approach designed to address a balance of three areas— knowledge, attitude and skill.

3. Decision-making-

We need to take proper decisions by controlling different confusing thinking patterns.

4. Creative thinking-

Need to take part in different creative acts like dance, drama, painting, sports, song and other cultural activities that will help to control emotions.

5. Problem-solving-

Identify the root of the problem and search for a suitable way to overcome this.

Problems Solving Four basic steps in problem-solving

1.  Defining problems—
   Predict the problem
   Understand the root cause and not the symptoms
   Understand the complexity.
2. Generating alternatives (Brainstorming tools and techniques) .
3.  Evaluating and selecting alternatives (Decision making tools and techniques)
4.  Implementing solutions.

 

6.  Interpersonal communication-

It is very important to develop the habit to be a patient listener. It is also important to learn what to speak and how to speak.

7. Interpersonal relationship-

It is important to build perfect bonds with family members, friends, neighbours and other people around you. Good relationship-making is an art and an important part of life skill education. Problem-solving is a systematic approach to defining the problem and creating a vast number of possible solutions without judging this solution.

 

8. Empathy –

Understand the problems and feelings of others and treat it and express them.

9. Stress management

Identify the cause of mental pressure and practice the measures to reduce them. Engage yourself in a different type of work.

“Class 8 WBBSE General Science Chapter 9, Endocrine System easy explanation”

10. Emotion management-

Need to be aware about one’s own feelings and express those feelings properly. Need to control your emotions before expressing it. Say’No’ if the situation demand. We often fear if we say ‘no’ it will harm our relationship but if saying ‘no’ is good to solve the problem then it is right.

Life skills:

Life skills include psycho-social competence and interpersonal skills that help people make informed decisions solve problems, think critically and creatively communicate effectively build healthy relationships empathize with others and cope with managing their lives in a healthy and productive manner.

Why Life Skills Education?

Life Skills Education Because Of

1. Early identification of problems early intervention and support at key moments in the lives of young people is vital. Development of psycho-social abilities.
2. To build different dimensions of well-being by building self-image and self-worth which in turn help individuals to be less vulnerable to the variations within a given context.