Endocrine System and Adolescence Chapter Notes | Home Economics for JSS 1 PDF Download

Introduction

The endocrine system is a special system in our body that helps control many important activities. It has glands that make chemicals called hormones. These hormones travel through the blood and tell different parts of the body what to do, like growing, staying active, or managing stress. Adolescence is the time when a child starts becoming an adult, usually between 10 to 19 years. During this time, the body changes a lot because of hormones, like growing taller, getting stronger, and even feeling new emotions. This chapter will teach us about the endocrine glands, the hormones they make, and how they help us during adolescence.

The Endocrine Glands

• Our body has two types of glands: exocrine glands and endocrine glands.
• Exocrine glands send their secretions through ducts (tubes) to the target organs, like salivary glands, pancreas, and sweat glands.
• Endocrine glands do not have ducts; they release their secretions directly into the blood, called hormones, which are carried to the target organs.
• Endocrine glands are also called ductless glands because they release hormones directly into the blood.
• Hormones are chemical substances made by endocrine glands that travel through the blood and act on specific organs or cells.
• Important endocrine glands in our body are thyroid, adrenal, pancreas, and pituitary glands.

Thyroid Gland

The thyroid gland is a bilobed (two-part) gland located on either side of the windpipe, just below the larynx. It secretes a hormone called thyroxine, which controls the metabolic rate (how fast the body uses energy).

Insufficient Secretion of Thyroxine

A lack of thyroxine hormone can lead to the following three health issues:

• Simple Goitre: This condition occurs when the thyroid gland becomes enlarged, forming a noticeable swelling in the neck. It is mainly caused by a deficiency of iodine in the daily diet.
• Cretinism: This disorder affects children and leads to improper physical and mental development. It may result in both mental and physical disabilities.
• Myxoedema: Seen in adults, this condition arises when too little thyroxine is produced. It causes symptoms such as fatigue, puffiness in the face and hands, and overall sluggishness.

Oversecretion of Thyroxine

When too much thyroxine is produced, it causes the thyroid gland to enlarge. This leads to a faster metabolism, rapid heartbeat, and a feeling of restlessness.

Adrenal Glands

• Adrenal glands are like caps over the two kidneys; each gland has a central medulla and outer cortex.
• The adrenal medulla secretes adrenaline hormone when a person is under severe stress, either physical (like injury) or emotional (like fear or anger).
• Adrenaline is called the "fight or flight" hormone because it prepares the body to either fight the danger or run away from it.
• Adrenaline increases the heart rate, raises blood pressure, increases blood supply to muscles, and releases more glucose into the blood to give the body extra energy and strength to handle the stressful situation.

Pancreas

The pancreas is located behind the stomach and is a mixed gland (it acts as both exocrine and endocrine). It has clusters of hormone-secreting cells called islets of Langerhans.

Insulin helps reduce the amount of glucose in the bloodstream in three main ways:

• It transforms excess glucose into glycogen, which is then stored in the liver and muscles.
• It encourages body cells to use up extra glucose for producing energy and heat.
• It also helps convert the surplus sugar into fat.
• When the body doesn’t produce enough insulin, it leads to diabetes mellitus. People with this condition have high blood sugar levels. They often urinate more, lose a lot of water, feel excessively thirsty, and may experience weight loss and weakness.
• In some cases, the body produces too much insulin, which causes the blood sugar level to drop too low — a condition that can be dangerous and harmful.
• Glucagon, another hormone, works opposite to insulin. It breaks down glycogen stored in the liver into glucose, thereby increasing blood sugar levels.

Pituitary Gland

The pituitary gland is a pea-sized gland located below the brain. It secretes several hormones that control the activity of other endocrine glands in the body. The pituitary gland is also called the "master gland" because it controls other glands.
The pituitary gland produces several important hormones with key functions:

• The growth hormone helps control body growth, especially during teenage years. If the body makes too little of it, it can lead to dwarfism, while too much can cause gigantism.
• Another hormone from the pituitary supports sperm production in males and the formation of eggs (ova) in females.
• During childbirth, the pituitary gland releases hormones that trigger contractions in the uterus, helping with the delivery process.

Adolescence

Hormones play an important role in growth and how the body works during adolescence. Adolescence is the time when a child starts becoming an adult, usually between 10 to 19 years. During adolescence, the body goes through many physical and emotional changes because of hormones. These changes show that a child is growing up and is no longer a child but becoming an adult. The pituitary gland plays an important role in the birth process as it produces hormones that cause contraction of the muscles of the uterus during childbirth. Another hormone stimulates the breasts to produce milk after childbirth for feeding the baby. Table 5.1 below gives an account of four major hormones, their secreting glands, and their main functions.

Physical Changes

During adolescence, the body goes through many changes as it grows from a child to an adult. These changes happen because of hormones.

• Increase in height: The most noticeable change is growing taller. Height increases a lot during adolescence because the bones in the arms and legs become longer. The weight of the body also increases. Girls grow faster than boys at first, but boys catch up later. By the end of adolescence, boys are usually taller than girls. The height a person reaches depends on their parents’ height.
• Change in body shape: Boys and girls have different body shapes during adolescence. Boys get broader shoulders and a stronger body. Girls develop wider hips and a curvier body shape.
• Change in voice: During adolescence, the voice box (larynx) grows in both boys and girls. In boys, the voice box grows a lot and becomes noticeable, called Adam’s apple. Boys’ voices become deep and low. Girls’ voices also change but become high-pitched and softer. At first, the voice may sound rough because it takes time to adjust to the changes. This rough voice may last for a few months, but it becomes normal after some time.
• Increased activity of sweat and sebaceous glands: During adolescence, sweat glands and oil glands (sebaceous glands) become more active. This causes more sweating and oily skin. Many young people get pimples and acne on their face because of the extra oil on the skin.

Development of Sexual and Secondary Sexual Characters

During adolescence, the body starts preparing to become an adult. This includes changes that help boys and girls become capable of having children in the future.

• When adolescence starts, the testes in boys and ovaries in girls become active.
• Testes in boys start making sperms, and ovaries in girls start making eggs.
• This means the person is now capable of having children, which is called puberty.
• Puberty happens because of special chemicals called sex hormones.
• In boys, the testes make a hormone called testosterone.
• In girls, the ovaries make a hormone called oestrogen.
• These hormones are controlled by another hormone from the pituitary gland in the brain.
• Sex hormones cause many changes in the body.
• In boys, the voice becomes deep, hair grows on the face and chest, and hair grows on legs.
• Boys start shaving because of facial hair growth.
• In girls, breasts start developing, and the hips become wider.
• Fat increases in the thighs, giving girls a curvier body shape.
• These changes are called secondary sexual characters.
• During this time, boys and girls also start feeling more interested in the opposite sex.

Adolescence and the Related Problems

Adolescence is an important but challenging time. The body and mind go through many changes, which can cause some problems.

• Adolescence is a time of fast physical growth, but also emotional and mental changes.
• Some changes that happen during adolescence are:
• Boys and girls start worrying a lot about how their body looks.
• They feel shy about the changes in their body and compare themselves with others.
• Boys who don’t release semen during sleep may have a “wet dream.”
• Boys who release semen during sleep don’t have a “wet dream”; they just find semen when they wake up.
• Girls start having periods, which means bleeding from the vagina.
• This bleeding is caused by the lining of the womb (uterus) breaking down, and it is called menstruation.
• Periods may not be regular at first, but they happen every 28 days after some time.
• Bleeding lasts for about 5 days.
• During periods, girls use a sanitary pad or tampon to absorb the blood.
• These changes during adolescence are normal, but some people feel worried.
• If you are worried, you should talk to your parents or a counsellor at school.
• Sometimes, the changes in hormones can cause sadness or mood swings, but this is a normal part of growing up.

Adulthood

• Adulthood is the stage after adolescence when a person becomes fully grown.
• During adulthood, the body stops growing physically.
• A person gains a lot of emotional strength during this time.
• The values and lessons learned during childhood and adolescence help shape a person’s life.
• Adults focus on building a strong career, good relationships, and taking on responsibilities.

Importance of Personal Hygiene

Keeping the body clean is very important during adolescence because the body goes through many changes.

• During adolescence, the body produces more sweat and oil because of active glands.
• Stress can make this worse because stress causes the body to release chemicals that increase sweat and oil.
• If you don’t keep your body clean, it can lead to health problems like pimples or infections.
• Stress affects how your body works, like making your heart beat faster or making you breathe faster.
• Stress also causes mental health problems like sadness or anxiety.
• Managing stress is one of the most important things for a happy and healthy life.

Managing Stress

Effectively managing stress involves taking control of your habits, mindset, emotions, and how you respond to challenges. Even if life feels overwhelming, there are practical steps to help reduce pressure and regain balance. Stress management techniques can help you stay calm, reduce anxiety, and maintain mental and physical wellness. Many self-care strategies are available to prevent and cope with stress.

Helpful Stress Management Techniques

• Yoga: This practice unites the body and mind through poses, controlled breathing, and relaxation. Benefits of yoga include:
  • Better flexibility
  • Stronger and toned muscles
  • Improved breathing, energy, and vitality
  • Weight management
  • Enhanced sports performance
• Regular Exercise: Engaging in physical activity for 30–45 minutes at least three times a week can boost your health and sense of control. Activities like jogging, swimming, or team sports (e.g., cricket, football, or hockey) are great options.
• Healthy Sleep Habits: Sticking to a consistent and restful sleep schedule is essential for reducing stress and feeling refreshed.
• Reading: A calming and enriching activity that relaxes the mind and enhances knowledge.
• Positive Thinking: Adopting an optimistic outlook helps you enjoy daily life more and handle challenges better.
• Laughter: Laughing lifts your mood and increases happiness.
• Deep Breathing: Practicing slow, deep breaths can activate your body’s natural relaxation response.
• Meditation: Set aside 15–20 minutes daily in a quiet place. Sit comfortably with closed eyes, focus on your breathing, and try to clear your mind of worries while counting your breaths.
• Get Organized: Staying organized helps you manage your time and responsibilities more effectively, reducing feelings of chaos.
• Pursue Hobbies: Spend time on activities you love, such as reading, writing, listening to music, playing instruments, or solving puzzles — they bring joy and relaxation.