CBSE Class 7 Science Chapter 06 Adolescence A Stage Of Growth And Change MCQs Set 01

Answer: (B) Between 10 and 19 years

Explanation:
The chapter clearly states that adolescence is a period of rapid growth and development typically occurring between the ages of 10–19 years.

Answer: (B) Increase in oily secretions from the skin that can clog pores

Explanation:
Acne occurs due to an increase in oily secretions from the skin during adolescence that can clog the skin pores and lead to infections, as explained in the chapter.

Answer: (B) The growth of the voice box in the throat

Explanation:
The growth of the voice box in adolescent boys may be seen as a bump in the throat region and is called the Adam's apple, which leads to a hoarse-sounding voice.

Answer: (C) Increase in height and bone length

Explanation:
• Secondary sexual characteristics help distinguish males from females but are not directly involved in reproduction
• Changes like facial hair, beard development, and breast development are secondary sexual characteristics
• Increase in height, while a major physical change, is not classified as a secondary sexual characteristic since it affects both sexes similarly and is not specific to distinguishing genders.

Answer: (B) Every 21–35 days

Explanation:
The chapter states that the menstrual cycle recurs generally every 28–30 days, with many healthy girls having cycles ranging from 21–35 days, which is considered normal variation.

Answer: (C) Iron

Explanation:
The chapter notes that adolescents, especially girls, may suffer from blood-related health problems because of deficiency of iron or vitamin B12 in the body.

Answer: (B) Hormones influence mood and behaviour

Explanation:
Hormones play a crucial role in regulating growth and development, and some hormones influence mood and behaviour, which explains why emotions are stronger during adolescence.

Answer: (C) Seeking help from family, friends, parents, or teachers

Explanation:
The first step to overcoming addiction is seeking help and support from family and friends, and talking to trusted people such as parents or teachers, along with counselling and medical advice if needed.

Answer: (C) Development of breasts

Explanation:
The chapter specifically mentions that girls undergo changes in height and weight along with other body changes like development of breasts, which is a characteristic change observed in adolescent girls.

Answer: (C) Hormones

Explanation:
Hormones are certain chemicals produced in the body that play a crucial role in regulating various aspects of growth and development and are responsible for many changes during adolescence.

Answer: (B) To prevent infections and maintain comfort, especially in areas like armpits and pubic region

Explanation:
Maintaining body hygiene, particularly in the armpits and the pubic region, may protect adolescents from potential infections, making it an essential part of health care during this stage.

Answer: (C) Only slight changes in voice

Explanation:
The voice box grows in adolescent girls but it is not as big as in boys, leading to only slight changes in voice compared to the more noticeable changes observed in boys.

Answer: (C) Around 45–55 years

Explanation:
The chapter states that usually by the age of 45–55, menstruation stops naturally, marking the end of the reproductive capability in a woman's life.

Answer: (C) Using digital devices to harass others through misleading messages and false rumours

Explanation:
Cyberbullying involves the use of digital devices such as phones, computers, or online platforms to harass others by sending misleading messages, spreading false rumours, or sharing personal information without consent.

Answer: (B) Adolescence prepares the body for adulthood including development of reproductive capability

Explanation:
• Adolescence is a period when the body prepares for adulthood
• During this stage, the body undergoes external and internal changes
• Maturation of various parts involved in reproduction occurs
• By the end of adolescence, both boys and girls become capable of reproduction.

Answer: (D) Development of breasts

Explanation:
The chapter's opening dialogue specifically highlights Venkatesh noticing Devyani's increased height and Devyani commenting on Venkatesh's thin moustache and voice changes. Breast development is not part of their conversation, making it the correct answer.

Answer: (B) Development of breasts in girls

Explanation:
According to the chapter, secondary sexual characteristics help distinguish males from females but are not directly involved in reproduction. However, breast development in girls supports lactation, which is connected to reproduction. The other options (moustache, beard, shoulder broadening, and general body hair) are explicitly stated as not being directly involved in reproduction, making them true secondary sexual characteristics in the narrow sense, though the question asks what 'directly assists.' The chapter's nuance suggests breast development has a more direct link to reproductive function than purely distinguishing features.

Answer: (C) Height increase becomes most noticeable during adolescence, coinciding with other changes

Explanation:
The chapter states that from birth, body growth including height increase is continuous, but this increase becomes more prominent during adolescence—the same period when other observable and internal changes occur together.

Answer: (D) All boys developing identical patterns of body hair growth

Explanation:
• The chapter explicitly states variations in timing and appearance of hair growth is completely normal
• It notes some boys may have no significant hair growth
• This indicates diversity in patterns is expected
• All boys developing identical growth patterns would contradict the stated normalcy of variations

Answer: (C) Boys' voice box grows considerably, producing noticeable hoarseness; girls' voice box grows but less noticeably

Explanation:
The chapter clearly contrasts the two: in adolescent boys, growth of the voice box leads to noticeably hoarse voices, while in adolescent girls, the voice box also grows but not as much as in boys, resulting in only slight voice changes.

Answer: (B) Understanding emotions can help adolescents make better choices and respond thoughtfully

Explanation:
The chapter explicitly states: "Understanding how our emotions influence our behaviour and actions, can help us make better choices and respond to situations thoughtfully."

Answer: (B) The menstrual cycle is an important natural process and a sign of good reproductive health

Explanation:
The chapter explicitly identifies the menstrual cycle as "an important natural process and is one of the signs of good reproductive health," emphasizing its positive significance rather than viewing it as problematic.