Chapter 7: Reaching The Age of Adolescence

1. What is adolescence?

Period between childhood & adulthood with reproductive maturity changes.(Bachpan aur adulthood ke beech ka samay).

2. At what age does puberty generally begin in girls?

Around 10-12 years.

3. What causes the voice to become deep in boys?

Growth of the larynx (voice box).(Larynx ka bada hona).

4. Name the male sex hormone.

Testosterone.

5. Name the female sex hormone.

Estrogen.

6. Which gland produces testosterone?

Testes.

7. What is menarche?

First menstruation.(Pehla maasik dharm).

8. What is menopause?

Stoppage of menstruation.(Maasik dharm ka rukna).

9. How many pairs of chromosomes are in human cells?

23 pairs.

10. Which chromosomes determine a male child?

XY.

11. Which gland is the ‘master gland’?

Pituitary gland.

12. Which hormone controls blood sugar?

Insulin.

13. Name the disease caused by thyroxine deficiency.

Goitre.

14. What controls metamorphosis in insects?

Insect hormones.

15. Name one food item rich in iron.

Leafy vegetables, Jaggery, Amla, Meat.

1. List three changes common in both boys and girls during puberty.

• Increase in height 📏⬆️.
• Growth of hair in underarms and pubic region.
• Increased activity of sweat/oil glands (pimples Pimple ).

2. What are secondary sexual characters?

• Features that distinguish males from females physically.
• Develop during puberty due to sex hormones.
• Examples: Beard in boys 🧔, breast development in girls 🚺.

3. Name the male and female gonads and the hormones they produce.

• Male Gonads: Testes ♂️; Produce Hormone: Testosterone.
• Female Gonads: Ovaries ♀️; Produce Hormone: Estrogen (and Progesterone).

4. Explain menstruation briefly.

• Occurs monthly in females after puberty.
• If egg released by ovary is not fertilized, the thickened uterus lining breaks down.
• This lining, along with blood vessels and the unfertilized egg, is discharged. 🩸
• Called menstruation or periods.

5. Who determines the sex of the baby – mother or father? Explain how.

• The father determines the sex.
• Mother always provides X chromosome (Egg = X).
• Father provides either X or Y chromosome (Sperm = X or Y).
• If X sperm fuses -> XX (Girl 👧).
• If Y sperm fuses -> XY (Boy 👦).

6. Why is Iodine important for our body?

• Iodine is necessary for the thyroid gland to produce Thyroxine hormone.(Thyroid granthi ko Thyroxine banane ke liye Iodine chahiye).
• Thyroxine controls body’s metabolism (rate of chemical reactions).
• Deficiency leads to Goitre (swollen thyroid gland in neck).(Kami se Goitre hota hai).
• It’s also vital for metamorphosis in frogs.

7. Why is a balanced diet needed during adolescence?

• Adolescence is a time of rapid growth.(Tez vikas ka samay hai).
• Body needs proper nutrients for development: Proteins (building blocks), Carbs/Fats (energy), Vitamins/Minerals (functions).
• Prevents nutritional deficiencies.
• Supports overall physical and mental well-being.

8. How are hormones transported to target sites?

• Hormones are secreted by endocrine glands directly into the bloodstream.(Hormones endocrine granthiyon se seedhe khoon mein jaate hain).
• Blood circulates throughout the body.
• Hormones reach specific target organs or tissues via the blood.(Khoon ke jariye hormone apne target organ tak pahunchte hain).
• They then trigger specific actions at the target site. 🎯

9. What role does pituitary gland play during puberty?

• Acts as the master gland 🧠.
• Secretes hormones that stimulate testes (males) and ovaries (females).(Testes aur Ovaries ko stimulate karne wale hormone nikalta hai).
• This triggers the production of sex hormones (testosterone/estrogen).
• Which then cause the physical and reproductive changes of puberty.

10. Why tadpoles growing in iodine-deficient water fail to become frogs?

• Frog metamorphosis is controlled by Thyroxine hormone.(Mendhak ka metamorphosis Thyroxine se control hota hai).
• Thyroid gland needs Iodine to make Thyroxine.
• If water lacks Iodine, no/less Thyroxine is produced.(Agar paani mein Iodine nahi, toh Thyroxine nahi banega).
• Without sufficient Thyroxine, metamorphosis cannot happen, and tadpoles remain tadpoles.

11. Name the hormone produced by adrenal glands and state its function.

• Hormone: Adrenaline.
• Function: Helps body cope with stress, anger, excitement (‘fight or flight’ response). Maintains salt balance in blood. (Tanav/gusse se nipatne mein madad. Namak santulan banaye rakhta hai).

1. Explain the changes that occur during puberty.

Puberty brings significant physical & hormonal changes:

• Height Increase: Rapid growth spurt.
• Body Shape Change: Boys: broader shoulders, muscles develop. Girls: wider hips.
• Voice Change: Boys: voice deepens (Adam’s apple grows). Girls: high-pitched.
• Gland Activity: Increased sweat/oil -> acne/pimples common.
• Sex Organ Development: Testes produce sperm; Ovaries release eggs.
• Secondary Sexual Characters: Boys: facial/body hair. Girls: breast development, body hair.
• Mental/Emotional Maturity: Changes in thinking, self-consciousness, mood swings.

2. Describe the role of hormones in human reproduction.

Hormones orchestrate the entire reproductive process:

• Initiation (Puberty): Pituitary hormones stimulate testes (produce Testosterone) & ovaries (produce Estrogen).
• Testosterone (Male): Drives development of male organs, secondary characters (beard etc.), sperm production.
• Estrogen (Female): Drives development of female organs, secondary characters (breasts), egg maturation, menstrual cycle.
• Progesterone (Female): Also from ovaries, helps regulate cycle & pregnancy.
• Menstrual Cycle Control: Complex interplay of pituitary hormones (FSH, LH) and ovarian hormones (Estrogen, Progesterone) controls ovulation and uterine changes.
• Pregnancy Maintenance: Hormones like Progesterone are crucial.

3. Explain the menstrual cycle.

It’s a monthly cycle in females after puberty, preparing body for potential pregnancy:

1. Egg Maturation: An egg matures in one of the ovaries.
2. Uterus Lining Thickens: Uterus prepares a thick lining rich in blood vessels to receive a fertilized egg.
3. Ovulation: The mature egg is released from the ovary (around day 14).
4. Possibility 1 (Fertilization): If sperm fertilizes the egg, the zygote implants in the uterine lining, pregnancy begins, menstruation stops temporarily.
5. Possibility 2 (No Fertilization): If egg is not fertilized, the thick uterine lining is no longer needed.
6. Menstruation 🩸: The unfertilized egg and the uterine lining break down and are shed along with blood through the vagina (lasts ~3-5 days).

This cycle repeats approximately every 28-30 days until menopause.

4. Write short notes on: (a) Adam’s apple (b) Secondary sexual characters (c) Sex determination in unborn baby.

(a) Adam’s apple:

• The protruding part in the front of the neck, more prominent in boys. (Gale ke saamne ka ubhra hissa, ladkon mein zyada dikhta hai).
• It is the enlarged Larynx (voice box) due to growth during puberty.
• Causes the voice to become deep in boys.

(b) Secondary Sexual Characters:

• Physical features distinguishing males and females, developing at puberty.
• Not directly involved in reproduction process itself.
• Caused by sex hormones (Testosterone/Estrogen).
• Ex: Beard in males 🧔, Breast development in females 🚺.

(c) Sex Determination in Baby:

• Depends on sex chromosomes from parents.
• Female = XX (Eggs have X). Male = XY (Sperm have X or Y).
• Egg (X) + Sperm (X) = XX (Girl 👧).
• Egg (X) + Sperm (Y) = XY (Boy 👦).
• Father’s sperm determines the sex.

5. Discuss the importance of reproductive health and necessary measures during adolescence.

Maintaining health is vital during adolescent changes.

Importance:

Measures:

• Balanced Diet 🍎: For growth needs (Iron important).
• Personal Hygiene 🧼🚿: Regular bathing, cleanliness prevents infections.
• Physical Exercise 🏃: Keeps body fit, manages stress.
• Adequate Rest 😴: For growth and recovery.
• Mental Well-being 🧘🫂: Understand changes, manage emotions, seek support if needed.
• Avoid Drugs 🚫: Say NO to drugs/alcohol.

6. List different Endocrine glands and the hormones they secrete.

Major Endocrine Glands & Hormones:

• Pituitary Gland 🧠: Growth Hormone, Gonadotropins (FSH, LH), TSH, ACTH etc. (Controls other glands).
• Thyroid Gland: Thyroxine (needs Iodine).
• Adrenal Glands: Adrenaline.
• Pancreas: Insulin (and Glucagon).
• Testes ♂️ (Gonads): Testosterone.
• Ovaries ♀️ (Gonads): Estrogen, Progesterone.

7. Why do boys develop a deeper voice than girls during puberty?

• During puberty, under the influence of testosterone, the larynx (voice box) grows significantly larger in boys compared to girls.
• This enlarged larynx protrudes in the front of the neck and is often visible as the Adam’s apple.
• The vocal cords inside the larynx also grow longer and thicker in boys.
• Longer and thicker vocal cords vibrate at a lower frequency, resulting in a deeper, lower-pitched voice characteristic of adult males.
• In girls, the larynx grows much less, so their vocal cords remain shorter and thinner, leading to a higher-pitched voice.

8. Define hormones. Why are they called chemical messengers?

• Hormones: Hormones are non-nutrient chemical substances produced in trace amounts by endocrine glands in the body.
• Chemical Messengers: They are called chemical messengers because:
  • They are secreted directly into the bloodstream by endocrine glands.
  • Blood circulates them throughout the body.
  • They travel to specific target cells or organs located far from the gland where they were produced.
  • At the target site, they bind to specific receptors and deliver a “message” or instruction, triggering a specific physiological response or change (like growth, metabolism changes, puberty developments etc.).
• They essentially act as signals, coordinating various activities between different parts of the body.

9. What physical changes occur during the menstrual cycle in females?

The main physical changes directly related to the cycle are internal, but lead to menstruation:

• Ovarian Changes: Inside the ovary, an egg follicle develops and matures, eventually releasing the mature egg (ovulation). After ovulation, the remnant follicle (corpus luteum) forms and produces hormones. (Ovary ke andar anda vikasit hota hai aur release hota hai).
• Uterine Changes: The inner lining of the uterus (endometrium) becomes thicker, softer, and rich in blood vessels throughout the cycle in preparation to receive and nourish a fertilized egg. (Uterus ki andar ki parat moti, narm aur khoon ki naliyon se bharpur ho jaati hai).
• Menstruation 🩸: If fertilization doesn’t happen, the hormone levels drop, causing the thickened uterine lining to break down and shed. This shedding of the lining along with blood and the unfertilized egg is discharged as menstrual flow. (Agar fertilization nahi hota, toh moti uterine lining toot kar khoon aur ande ke saath bahar nikal jaati hai).

Other associated physical changes like cramps, bloating etc. can also occur but vary between individuals.

10. Write a note on the importance of a balanced diet and physical exercise during adolescence.

Adolescence requires special attention to diet and exercise:

Balanced Diet 🍎🥕🥛:

• Supports Rapid Growth: Provides energy (carbs/fats), building materials (proteins), and regulators (vitamins/minerals) needed for the growth spurt and development of muscles, bones, organs.
• Prevents Deficiencies: Ensures adequate intake of all essential nutrients like calcium (for bones) and iron (for blood, esp. girls).
• Overall Health: Builds a strong foundation for adult health. Junk food lacks essential nutrients and should be limited.

Physical Exercise 🏃🤸:

• Keeps Body Fit: Builds strong muscles and bones, improves cardiovascular health.
• Weight Management: Helps maintain a healthy weight.
• Stress Relief & Mood Boost: Reduces stress and improves mood, important during emotional changes of adolescence.
• Better Sleep: Promotes good sleep patterns.

Combining a balanced diet with regular physical activity is crucial for healthy physical and mental development during the demanding phase of adolescence.