MCQ(Solution) - Reaching The Age of Adolescence | Science Class 8 PDF Download

Q1: What is the primary physical change during puberty?

(a) Increased intellectual development
(b) Broadening of shoulders and chest in boys
(c) Voice box enlargement in girls
(d) Decrease in height

Correct Answer is Option (b)

• The primary physical change during puberty is the broadening of shoulders and chest in boys.
• This change occurs due to growth and increased muscle development.
• It is one of the most noticeable transformations that signify the onset of puberty.

Q2: What triggers the increased secretion of sweat and oil glands during puberty? 

(a)  Intellectual development
(b) Hormones
(c) Height growth
(d)  Muscle development 

Correct Answer is Option (b)

The increased secretion of sweat and oil glands during puberty is primarily triggered by hormones. These chemical substances play a crucial role in regulating various changes in the body, including:

• Activation of sweat glands
• Increased oil production in sebaceous glands
• Development of acne and pimples due to heightened gland activity

Overall, hormones are essential for the physical changes that occur during this stage of development.

Q3:  Which hormone is responsible for the development of facial hair in boys during puberty? 

(a)  Estrogen
(b)  Thyroxine
(c)  Testosterone
(d)  Insulin 

Correct Answer is Option (c)

• Testosterone is the hormone that triggers the growth of facial hair in boys during puberty.
• This hormone is produced by the testes and plays a key role in developing male characteristics.

Q4:  When does the menstrual cycle typically begin for females? 

(a) 6-8 years
(b)  10-12 years
(c) 14-16 years
(d) 18-20 years 

Correct Answer is Option (b)

The menstrual cycle, which starts with menarche, usually begins for females between the ages of:

10 to 12 years
During this time, the body undergoes significant changes, marking the start of reproductive capability.

Q5:  What is the role of the pituitary gland in puberty-related changes? 

(a) It regulates the production of sex hormones
(b)  It controls voice box growth
(c)  It influences muscle development
(d) It triggers height spurts 

Correct Answer is Option (a)

The pituitary gland is vital during puberty as it:

• Regulates the production of sex hormones.
• Stimulates the growth of reproductive organs.
• Influences physical changes such as height and muscle development.
• Controls the development of secondary sexual characteristics.

Overall, it triggers significant changes that prepare the body for reproduction.

Q6: Which hormone is produced by the ovaries and contributes to breast development in girls? 

(a) Testosterone
(b) Insulin
(c) Estrogen
(d) Thyroxine 

Correct Answer is Option (c)

• Estrogen is the primary female hormone produced by the ovaries.
• It plays a crucial role in breast development during puberty in girls.
• This hormone helps in the formation of mammary glands within the breasts.

Q7:  What is the term for the period when menstrual cycles cease, typically around 45 to 50 years of age? 

(a) Menarche
(b) Menstruation
(c) Menopause
(d)  Metamorphosis 

Correct Answer is Option (c)

• The term menopause refers to the time when menstrual cycles stop.
• This typically occurs between the ages of 45 and 50.
• During menopause, a woman no longer experiences monthly periods.

Q8:How is the sex of the baby determined? 

(a) Mother's hormones
(b)  Father's hormones
(c)  Random genetic factors
(d) Combination of X and Y chromosomes 

Correct Answer is Option (d)

The sex of the baby is determined by the combination of X and Y chromosomes:

• Females have two X chromosomes (XX).
• Males have one X and one Y chromosome (XY).
• The egg always carries an X chromosome.
• Sperms can carry either an X or a Y chromosome.

If a sperm with an X chromosome fertilises the egg, the baby will be female. If a sperm with a Y chromosome fertilises the egg, the baby will be male.

Q9:  What hormone, produced by the thyroid gland, is necessary for tadpole growth into adults during frog metamorphosis? 

(a) Testosterone
(b) Estrogen
(c) Thyroxine
(d) Insulin 

Correct Answer is Option (c)

Thyroxine Thyroxine is a hormone produced by the thyroid gland. It plays a crucial role in the growth of tadpoles into adult frogs during metamorphosis. Key points include:

• Essential for metamorphosis from tadpole to adult frog.
• Requires iodine in the water for proper production.
• Without sufficient thyroxine, tadpoles cannot mature.

Q10:Why is saying "NO" to drugs emphasized during adolescence? 

(a)Drugs hinder intellectual development
(b) Drugs are addictive and harmful to health
(c) Drugs promote muscle development
(d) Drugs enhance height growth 

Correct Answer is Option (b)

Saying 'NO' to drugs is crucial during adolescence for several reasons:

• Addiction: Drugs can lead to addiction, making it hard to stop once you start.
• Health Risks: They can cause serious harm to both physical and mental health.
• Impact on Well-being: Drug use can negatively affect happiness and overall quality of life.