Short Answer Type Questions – Topic-wise

1. Adolescence and PubertyBasic Concepts

Understanding the meaning of adolescence and puberty, and their age range.

• Q1. Define adolescence.

  Ans. Adolescence is the period of life between childhood and adulthood during which a child gradually develops into an adult. It involves rapid physical, mental and emotional changes and usually begins around 11 years of age and continues till about 18–19 years.

• Q2. How is puberty related to adolescence?

  Ans. Puberty is a part of adolescence. It is the stage during adolescence when the reproductive organs mature and the body becomes capable of reproduction. Thus puberty marks the beginning of sexual maturity within the broader period of adolescence.

• Q3. Why is adolescence called a “transition period”?

  Ans. Adolescence is called a transition period because it is the stage in which a person moves from childhood to adulthood. During this time, the body, mind, behaviour and social roles change rapidly, preparing the individual for adult life.

• Q4. State the approximate age range of adolescence in humans.

  Ans. In humans, adolescence generally starts around 11 years of age and may continue up to 18–19 years. The exact age can vary slightly from person to person due to differences in health, nutrition and heredity.

• Q5. Why are adolescents often called teenagers?

  Ans. Adolescents are called teenagers because most of the years of adolescence fall between 13 and 19, and these numbers have the word “teen” in their names (thirteen, fourteen, etc.). The term “teenager” therefore refers to children in their adolescent years.

• Q6. Explain why there is variation in the age at which puberty begins.

  Ans. The age at which puberty begins is not the same for all individuals because it depends on factors like nutrition, general health, climate and heredity. For example, well-nourished children often reach puberty earlier than undernourished children, and girls usually reach puberty earlier than boys.

• Q7. How does the onset of puberty differ in boys and girls?

  Ans. In general, girls attain puberty between 10–12 years, whereas boys usually attain puberty between 12–14 years. Thus girls typically show signs of puberty a little earlier than boys, although there are individual differences.

2. Physical Changes at PubertyBody Growth & Appearance

Growth spurt, change in body shape, voice and activity of glands.

• Q8. What is a growth spurt? When does it occur?

  Ans. A growth spurt is a sudden and noticeable increase in height and body size over a short period of time. It usually occurs during puberty when the long bones of the arms and legs grow quickly, making adolescents appear taller within months or a few years.

• Q9. Give two differences in body shape between boys and girls at puberty.

  Ans. At puberty, girls develop broader hips and a more rounded body shape, while boys develop broader shoulders and a wider chest. Additionally, boys show more muscle development as compared to girls, whose body fat distribution changes to prepare for childbearing.

• Q10. Why does the height of some adolescents continue to increase even after 18 years?

  Ans. Height increases as long as the growth plates at the ends of long bones remain open. In some adolescents, these growth plates close a little later, so their bones can continue to lengthen slightly beyond 18 years, causing height to increase for a short period more.

• Q11. What changes occur in the voice of boys at puberty?

  Ans. At puberty, the voice box or larynx in boys grows larger and the vocal cords become longer and thicker. This makes the voice deeper and heavier. During this process the voice may “crack” or break for some time before becoming clear and deep.

• Q12. What is Adam’s apple and why is it more prominent in boys?

  Ans. Adam’s apple is the bulge seen in the front of the throat due to the enlarged larynx. It is more prominent in boys because their larynx enlarges much more during puberty than in girls, causing the front part of the throat to project outward visibly.

• Q13. Why do adolescents tend to sweat more and may suffer from acne?

  Ans. During adolescence, sweat glands and sebaceous (oil) glands become overactive under the influence of hormones. This leads to more sweating and increased oil secretion on the skin. The extra oil can block skin pores, causing pimples or acne, especially on the face.

• Q14. How do the reproductive organs in boys change at puberty?

  Ans. In boys, the testes and penis increase in size at puberty. The testes start producing sperm and the male sex hormone testosterone. These changes make the male reproductive system functional and capable of reproduction.

• Q15. Describe the changes in the reproductive organs of girls at puberty.

  Ans. In girls, the ovaries enlarge and begin to release mature eggs (ova) regularly. The uterus and vagina also grow in size. Breasts develop and the menstrual cycle begins, indicating that the girl’s reproductive system has become functional.

• Q16. Why might adolescents sometimes feel awkward about their changing bodies?

  Ans. Adolescents may feel awkward because the changes in height, body shape, voice and appearance happen quickly and not always at the same rate in everyone. They may compare themselves with friends and worry about looking different, which can cause embarrassment or confusion if they do not understand that these changes are natural and normal.

3. Secondary Sexual Characters and Sex HormonesMale & Female Differences

Features that differentiate adult males and females and the hormones controlling them.

• Q17. What are secondary sexual characters? Give two examples.

  Ans. Secondary sexual characters are physical features that distinguish males from females but are not directly involved in reproduction. Examples include the growth of beard and moustache in boys and the development of breasts in girls.

• Q18. List any three secondary sexual characters that appear in boys at puberty.

  Ans. In boys, secondary sexual characters include growth of facial hair such as moustache and beard, broadening of shoulders, growth of hair on chest and in the armpits, and deepening of the voice. Any three of these may be written in the exam.

• Q19. List any three secondary sexual characters that appear in girls at puberty.

  Ans. In girls, secondary sexual characters include development of breasts, broadening of hips, and growth of hair in the armpits and pubic region. These changes give the female body its typical adult shape.

• Q20. What is the role of testosterone in boys?

  Ans. Testosterone is the main male sex hormone secreted by the testes. It stimulates the development of secondary sexual characters in boys such as facial hair, deep voice, and broad shoulders, and also helps in the production of sperms in the testes.

• Q21. What is the role of oestrogen in girls?

  Ans. Oestrogen is the main female sex hormone secreted by the ovaries. It brings about the development of secondary sexual characters in girls, such as development of breasts and broadening of hips, and regulates the menstrual cycle and development of female reproductive organs.

• Q22. How does the pituitary gland control the release of sex hormones?

  Ans. The pituitary gland secretes specific hormones that stimulate the testes in boys to produce testosterone and the ovaries in girls to produce oestrogen. Thus the pituitary acts as a master gland and indirectly controls the onset of puberty and the development of secondary sexual characters through sex hormones.

• Q23. Why are sex hormones produced only after puberty?

  Ans. Sex hormones are produced only after puberty because the pituitary gland starts secreting hormones that activate the reproductive glands at this stage. Before puberty, the gonads are not active enough, so the level of sex hormones is low and the body does not show adult sexual characteristics.

4. Hormones and Endocrine GlandsHormonal Control

Definition of hormones, endocrine glands and their functions.

• Q24. What are endocrine glands? How are they different from other glands?

  Ans. Endocrine glands are ductless glands that secrete hormones directly into the bloodstream. They differ from other glands like sweat or salivary glands, which release their secretions through ducts onto the surface of organs or outside the body.

• Q25. Name any four endocrine glands found in the human body.

  Ans. Four endocrine glands in the human body are: pituitary gland, thyroid gland, pancreas, adrenal glands, testes in males and ovaries in females. Any four of these can be written in the exam answer.

• Q26. What is the function of the thyroid gland?

  Ans. The thyroid gland secretes the hormone thyroxine, which controls the body’s metabolism and influences growth and development. Lack of thyroxine can lead to stunted growth and other health problems, while its excess can also be harmful.

• Q27. How does the pancreas act as an endocrine gland?

  Ans. The pancreas acts as an endocrine gland by secreting the hormone insulin. Insulin helps to control the level of sugar (glucose) in the blood. If insulin is not produced in sufficient quantity, it may lead to a disease called diabetes.

• Q28. What are adrenal glands and what is their main function?

  Ans. Adrenal glands are small glands located above the kidneys. They secrete hormones like adrenaline that help the body to respond quickly to stress or emergency situations by increasing heartbeat, breathing rate and energy supply, preparing the body for “fight or flight”.

• Q29. Why is the pituitary gland called the master gland?

  Ans. The pituitary gland is called the master gland because it secretes hormones that control the activity of other endocrine glands such as thyroid, adrenal glands, testes and ovaries. By regulating these glands, the pituitary indirectly controls growth, reproduction and many other body functions.

• Q30. How do hormones reach their target organs?

  Ans. Hormones are released by endocrine glands into the blood. They travel with the blood throughout the body and act only on specific target organs or tissues that recognise them. In this way, hormones carry messages from the glands to different parts of the body.

• Q31. What may happen if the growth hormone is secreted in less or excess amount?

  Ans. If the growth hormone is secreted in less amount during childhood, it can cause stunted growth or dwarfism. If it is secreted in excess, it can cause abnormal increase in height, leading to gigantism, which may create health problems for the individual.

5. Reproductive Phase and MenstruationHuman Reproduction

Reproductive phase in boys and girls, menstrual cycle and related terms.

• Q32. What is meant by the reproductive phase of life?

  Ans. The reproductive phase of life is the period during which a person is capable of producing offspring. In this phase, the reproductive organs are fully functional and gametes (sperms in males and ova in females) are produced regularly.

• Q33. When does the reproductive phase begin in girls and when does it end?

  Ans. In girls, the reproductive phase begins with the onset of menstruation or menarche, usually around 10–12 years of age. It ends with menopause, when menstruation naturally stops, usually between 45–50 years of age.

• Q34. Define menarche and menopause.

  Ans. Menarche is the first menstrual flow in a girl, marking the beginning of the reproductive phase. Menopause is the natural stoppage of menstrual cycles in a woman, indicating the end of the reproductive phase.

• Q35. Explain briefly what happens in the uterus during one menstrual cycle.

  Ans. During each menstrual cycle, the uterus develops a thick, soft lining rich in blood vessels to receive a fertilised egg. If fertilisation does not occur, this lining breaks down and along with blood and mucus is released through the vagina as menstrual flow. This cycle repeats roughly every 28–30 days.

• Q36. What is menstruation? How long does it normally last?

  Ans. Menstruation is the monthly discharge of blood and tissue from the uterus through the vagina when fertilisation does not occur. It usually lasts for about 3–5 days in most girls and women, though the exact duration may vary slightly from person to person.

• Q37. Why is it important for girls to maintain good hygiene during menstruation?

  Ans. It is important to maintain good hygiene during menstruation because the moist environment and presence of blood can allow harmful germs to grow, leading to infections of the reproductive tract. Using clean sanitary pads, changing them regularly and keeping the genital area clean helps prevent infection and ensures good health.

• Q38. How is the reproductive phase in boys different from that in girls?

  Ans. In boys, the reproductive phase begins when the testes start producing sperms at puberty and may continue for a longer time, sometimes even into old age. In girls, the reproductive phase is more clearly defined and lasts from menarche to menopause, usually between 10–12 years and 45–50 years of age.

6. Sex Determination in HumansChromosomes & Inheritance

Chromosomes, sex chromosomes and how they decide boy or girl.

• Q39. What are chromosomes? How many chromosomes are present in human body cells?

  Ans. Chromosomes are thread-like structures present in the nucleus of cells that carry hereditary information in the form of genes. In humans, each body cell (except gametes) contains 46 chromosomes arranged in 23 pairs.

• Q40. What are sex chromosomes? Name the sex chromosomes in males and females.

  Ans. Sex chromosomes are a pair of chromosomes that determine the sex of an individual. Females have two X chromosomes (XX), whereas males have one X and one Y chromosome (XY).

• Q41. How do sex chromosomes determine whether a child will be a boy or a girl?

  Ans. All eggs from the mother carry an X chromosome. Half of the sperms from the father carry an X chromosome and the other half carry a Y chromosome. If a sperm with X fertilises the egg (X), the zygote becomes XX – a girl; if a sperm with Y fertilises the egg, the zygote becomes XY – a boy.

• Q42. Why is the father responsible for determining the sex of the child?

  Ans. The father is responsible because he produces two kinds of sperms – one with X and one with Y chromosome, while the mother produces only one kind of egg with X chromosome. Whether the child is a boy or a girl depends on whether an X-bearing or Y-bearing sperm fertilises the egg.

• Q43. Why is it scientifically wrong to blame the mother for the birth of a girl child?

  Ans. It is wrong to blame the mother because she always contributes only an X chromosome through her egg. The sex of the child is decided by the father’s sperm, which may carry either X or Y. Thus, scientifically, both parents contribute equally and the mother cannot be held responsible for the baby’s sex.

• Q44. What values are promoted by understanding the scientific basis of sex determination?

  Ans. Understanding sex determination promotes values like gender equality, respect for girls, and freedom from superstitions and discrimination. It helps society realise that the birth of a girl or boy is a natural and scientific process, not something to be blamed on either parent.

7. Health, Hygiene and Emotional Changes in AdolescenceHealthy Growing Up

Balanced diet, personal hygiene, exercise, emotions and harmful habits.

• Q45. Why do adolescents need a balanced diet? Name its main components.

  Ans. Adolescents grow very rapidly, so they need a balanced diet to provide all the nutrients required for healthy growth and development. A balanced diet includes proper amounts of carbohydrates, proteins, fats, vitamins, minerals, water and roughage, taken through a variety of wholesome foods like cereals, pulses, milk, fruits and vegetables.

• Q46. Suggest any four healthy food habits for adolescents.

  Ans. Four healthy food habits for adolescents are: eating regular meals without skipping breakfast, including plenty of fruits and green vegetables, taking adequate milk or other protein sources, drinking enough water, and limiting junk food, soft drinks and very oily snacks. These habits support proper growth and prevent lifestyle diseases.

• Q47. Give reasons why personal hygiene is very important for adolescents.

  Ans. Personal hygiene is very important because sweat and oil secretion increase during adolescence, which can lead to body odour, skin problems and infections if cleanliness is ignored. Regular bathing, clean clothes and proper care during menstruation help prevent bacterial growth and keep adolescents healthy and confident.

• Q48. How does regular physical exercise benefit adolescents physically and mentally?

  Ans. Regular physical exercise strengthens bones and muscles, improves blood circulation and lung capacity, and maintains a healthy body weight. Mentally, it helps reduce stress, improves mood and concentration, and builds self-confidence, which is very useful during the emotionally sensitive adolescent years.

• Q49. What emotional changes are commonly seen during adolescence? How should they be handled?

  Ans. During adolescence, children may experience mood swings, sensitivity, curiosity about their identity and strong emotions like anger or sadness. These changes should be handled by talking openly with parents and teachers, seeking guidance, choosing good friends and practising self-control and positive thinking instead of acting impulsively.

• Q50. Why should adolescents firmly say “No” to smoking, alcohol and drugs?

  Ans. Adolescents should say “No” because smoking, alcohol and drugs harm the brain, lungs, liver and heart, reduce concentration and academic performance and can lead to addiction and serious diseases. Avoiding these substances protects their health and future and reflects responsible behaviour.