NCERT Solutions for Class 8 Science Chapter 10
Science is a broad discipline that studies the structure and behaviour of the physical and natural world through observation and experimentation. Biology, chemistry, and physics are the three subjects of science education studied most often. Science is a human undertaking that spans the globe. The scientific process involves people from across the world. And you, unknowingly, are a part of it.
NCERT Class 8 Science Chapter 10 is about Reaching the Age of Adolescence. This chapter help students learn about adolescence, puberty changes, hormones in youth, sexual maturity in males and females, and menstrual cycles. Puberty, sexual characteristics, the roles of hormones in females, sex determination, and reproductive health care are covered in the chapter.
Extramarks NCERT solutions provide detailed and authentic answers to all the textbook questions. Through those, the students can understand, remember and retain answers to NCERT questions and thus, perform well in exams.
Class 8 Science Chapter 10 is built with many concepts, and to grasp each of those, students should go through the NCERT Solutions. As a result, Extramarks has developed Class 8 Science Chapter 10 Solutions. NCERT Solutions Class 8 Science Chapter 10 has been created exclusively by Extramarks experts.
Apart from NCERT Solutions for Class 8 Science Chapter 10, Extramarks is full of study material for all classes. In addition to these, students can use the Extramarks website to access several other study tools. For example, NCERT books, CBSE revision notes, CBSE sample papers, CBSE previous year question papers, and other materials are available to students.
Key Topics Covered in NCERT Solutions for Class 8 Science Chapter 10
To make it convenient for the students, Extramarks has listed below are key topics that are covered in NCERT Solutions for Class 8 Science Chapter 10:
| Introduction to Adolescence and Puberty |
| Changes during Puberty |
| Talking about the Glands |
| Secondary sexual characteristics |
| Menstrual Cycle |
| Reproductive Phase in Human Lives |
| Sex Determination |
| Nutrition, Hygiene and Balanced Diet |
| Saying NO to Drugs |
Let us look at Extramarks in-depth information on each subtopic in NCERT Solutions for Class 8 Science Chapter 10- Reaching the Age of Adolescence.
Introduction to Adolescence and Puberty
Extramarks NCERT Solutions for Class 8 Science Chapter 10 describes adolescence as the stage of life when the body experiences changes that lead to reproductive maturity. This is the period during which a youngster matures into an adult.
- Adolescence starts at the age of 11 and lasts until 18 or 19.
- Teenagers are another term for adolescents.
- Puberty is defined by significant changes in the body that occur throughout this time.
Puberty is when the human body and reproductive systems undergo several changes that ultimately lead to sexual maturity.
- The most notifiable change throughout puberty is that boys and girls become competent reproductively.
- Puberty can start a year or two later in males than in girls.
Changes during Puberty
NCERT Solutions for Class 8 Science Chapter 10 by Extramarks explains the different changes everybody undergoes during puberty:
- Increase in Height: When a child approaches puberty, their height starts increasing. Long bones develop quickly, resulting in a rise in height. By the age of 18, a person has reached their maximum height.
- Change in Body Shape: Boys develop muscularity. Their shoulders expand, and their waist narrows. The girls’ waists broaden, and their shoulders shrink.
- Change in Voice: The boys’ voices become thick and harsh. This occurs as the voice box grows in size. The females’ voices are generally high-pitched.
- Increased activity of Sebaceous and Sweat Glands: Because perspiration and sebaceous gland secretions rise during this period, many teens get acne.
- Development of Sex Organs: The testes and penis of boys grow, and sperm production begins. Girls’ ovaries develop and begin to release mature eggs.
Talking about the Glands
Extramarks NCERT Solutions for Class 8 Science Chapter 10 discusses the types of Glands and their functions in the human body.
Endocrine Gland
An endocrine system can be defined as a collection of ductless glands that secrete chemical molecules called hormones to regulate body processes and functions.
- They immediately push their secretions into circulation.
- Hormones frequently have a long distance between their source and the location of the action.
Hormones
Endocrine glands release hormones, which are chemical messengers. They oversee bodily functions, physiology, and behaviour.
Pituitary Gland
The master of all glands is the pituitary gland. This pea-sized structure is found at the base of the brain. Other glands in the body are controlled and regulated by them. For example, growth hormone, thyroid-stimulating hormone, LH, FSH, and other hormones are secreted by this gland.
- The pituitary gland produces growth hormones, regulating a person’s general growth.
- Growth hormone secretion is at its peak throughout adolescence.
Testosterone
- The predominant male sex hormone is testosterone.
- This is also one of the key hormones responsible for the development of male secondary sexual traits as well as for the development of male reproductive organs and sperm production.
- Only during puberty do the testes begin secreting testosterone.
Oestrogen
- The predominant female sex hormone is estrogen/oestrogen.
- Oestrogen oversees the development of female reproductive organs, creating female gametes (ova), secondary sexual traits, and the menstrual cycle.
- After puberty, the ovaries release this hormone.
Thyroid Gland
- In the neck, it is a butterfly-shaped gland.
- It produces the hormone thyroxine.
- This hormone is essential because it keeps all metabolic functions in control.
- A lack of this hormone can cause thyroid gland enlargement, resulting in goitre.
Pancreas
Insulin is a hormone produced by the pancreas that controls blood sugar levels. Diabetes is caused by insulin deficiency.
Adrenal Glands
- The adrenal glands reside just above the kidneys.
- They change form during a person’s life and shrink as they get older.
- They emit the hormone adrenaline and regulate salt and pH levels.
- Because it acts in emergency conditions, the hormone adrenaline is sometimes known as the “fight or flight” hormone.
Secondary sexual characteristics
NCERT Solutions for Class 8 Science Chapter 10 describes Sexual characteristics are physical or behavioural features identifying a living being’s biological sex. These are the characters:
- Primary Sexual Characteristics: The sex organs utilised for reproduction with which a person is born are known as primary sexual characteristics. Testes in men and ovaries in females, for example.
- Secondary Sexual Characteristics: Secondary sexual characteristics are traits that distinguish the sexes of a group of organisms that emerge throughout puberty.
The following are some of the sexual characteristics that males and females develop:
Boys grow beards, moustaches, and hair beneath their armpits, chests, and genital areas. They gain muscular mass and broaden their shoulders. They gain weight, and their voices become hushed.
In girls, the size of breasts grows. Their hips expand, and their vaginal region expands. Girls’ voices rise high-pitched throughout their menstrual cycle. They grow hair in their armpits and pubic areas as well.
Extramarks NCERT Solutions have defined secondary Sexual Characteristics for Class 8 Science Chapter 10 in the above passage. To get more details on it, refer to the Extramarks website.
Menstrual Cycle
NCERT Solutions for Class 8 Science Chapter 10 by Extramarks describes all aspects of the Menstrual cycle in females in the following:
- Menstruation is a female-only reproductive cycle.
- Menarche, also known as the start of the menstrual cycle, occurs during puberty.
- Both the ovaries and the uterus go through cyclic alterations during the process.
- An ovum grows and develops in the ovaries before being moved out.
- A thick spongy inner lining extends inside the uterus in preparation for pregnancy.
- Pregnancy happens when the egg is fertilised. If fertilisation does not occur, the free egg and the thicker uterine lining and blood vessels are lost if fertilisation does not occur.
- In women, this results in menstruation or bleeding. Women’s menstrual cycles tend to end between 45 and 52.
- Menopause is the stoppage of the menstrual cycle.
- Between menarche and menopause, a woman’s reproductive age can be determined by her ability to have children.
Reproductive Phase in Human Lives
NCERT Solutions for Class 8 Science Chapter 10 highlights that the Adolescents’ testes and ovaries begin to create gametes after they enter puberty, therefore capable of reproduction.
When a girl hits puberty, usually between the ages of 10 and 12, she enters the reproductive period of her life. It lasts until a female is 45-50 years old.
The ova in a woman’s ovaries begin to develop at the start of adolescence, and one mature ovum is discharged once every 28-30 days. When an ovary releases an egg, this process is called ovulation. The uterine wall thickens currently to receive the fertilised egg. After fertilisation, the fertilised egg is implanted in the thick uterine wall, resulting in pregnancy.
For the cycles when fertilisation does not occur, the released egg and the uterine wall lining are released through the blood flow known as menstruation.
A woman’s reproductive life begins with menarche (her first menstrual flow) and concludes with menopause (when the menstrual cycle stops at 45-50 years of age).
Sex Determination
To comprehend how sex is determined, we must first understand the following procedure:
- Humans have 23 chromosome pairs. Out of these 23 pairs, all 22 are Autosomes, and only one is what we refer to as the ‘Sex Chromosome,’ which is majorly involved in the sex determination process.
- Both genders have two-sex chromosomal sets.
- Males have one chromosome each of the X and Y chromosome (XY), both active.
- Females have two X (XX) chromosomes, one of which is active.
- Humans, mammals, insects, and a few plant species have the XY sex-determination mechanism.
- Whether they are boys or girls, all children get one X chromosome from their mother. The kind of chromosome acquired from their father will decide the sex of the offspring.
- A male will inherit the Y chromosome, whereas a girl will receive the X chromosome.
Balanced Diet, Hygiene and Physical Exercise
Balanced Diet
Adolescence is a period of rapid physical growth. As a result, all the nutrients are required by a developing person. As a result, all teens should eat a well-balanced diet rather than junk food.
A balanced diet contains the right amounts of proteins, carbs, fats, and vitamins. Junk food hurts a person’s development.
Personal Hygiene
Aside from consuming a healthy diet, it’s critical to keep our bodies and surroundings clean to avoid infections and illness. Adolescents must embrace personal hygiene practices such as bathing every day, washing hands before and after meals, avoiding defecating in the open, and girls keeping cleanliness during their menstrual cycle.
If teenage males and girls do not maintain personal hygiene, they risk contracting bacterial diseases.
Physical Exercise
Extramarks NCERT Solutions for Class 8 Science Chapter 10 highlights that Exercise can be the primary reason that keeps the body and mind in good shape. Physical activity can be of numerous forms, including walking, playing, and practicing yoga.
NCERT Solutions have briefly described the concept of a Balanced Diet, Hygiene, and Physical Exercises for Class 8 Science Chapter 10. To get more information about the same, refer to the Extramarks website. The website is home to numerous study materials.
Saying NO to Drugs
- Drugs are addictive and cause long-term damage to the body.
- Drugs can sometimes cause irreparable damage.
- All youngsters should avoid drugs.
- By sharing syringes used to inject drugs, HIV can be transmitted from an infected person to a healthy person.
- It can also be passed on to a newborn through the mother’s milk if she is infected.
- The virus could also be spread due to sexual contact with an HIV-positive individual.
- People who are addicted to drugs have a higher risk of contracting HIV.
NCERT Solutions for Class 8 Science Chapter 10 Exercise and Solutions
Extramarks is a hub of quality study material. Students can use the study material prepared exclusively by Extramarks experts to excel in their examinations. Resources such as Past Year’s Question Paper, extra Notes, Question Answers, and many more are abundant. Click on the below links to view NCERT Solutions for Class 8 Science Chapter 10:
- Class 8 Civics Chapter 10: Very Short Answer Type Questions
- Class 8 Civics Chapter 10: Short Answer Type Questions
- Class 8 Civics Chapter 10: Long Answer Type Questions
Students can access NCERT Solutions for Class 8 Science Chapter 10 and other chapters by clicking here. In addition, students can also explore NCERT Solutions for other classes below.
By getting access to NCERT Solutions for Class 8 Chapter 10, students can easily understand all the concepts relating to adolescence.
NCERT Solutions Class 8 Science Chapter-wise List
Key Features of NCERT Solutions for Class 8 Science Chapter 10
NCERT solutions provide detailed and authentic answers to all the textbook questions. Through those, the students can understand, remember and retain answers to NCERT questions and thus, perform well in exams
Extramarks NCERT Solutions are popular among students, as these help them achieve their goal of getting better grades. Based on the benefits, it is advised for students to go through the Extramarks NCERT Solutions for Class 8 Science Chapter 10 to obtain good results. Extramarks has done a commendable job by creating these NCERT Solutions. But why choose Extramarks? Here’s why:
- Extramarks experts have exclusively created the NCERT Solutions after careful research and as per the needs of the students.
- The language in these Solutions has been made is straightforward and easy to understand.
- Based on the NCERT standards, Extramarks has compiled the most important material on this topic.