These AP 8th Class Biology Important Questions and 5th Lesson Reaching the Age of Adolescence Class 8 Extra Questions will help students prepare well for the exams.
Class 8 Science Reaching the Age of Adolescence Extra Questions
Reaching the Age of Adolescence Class 8 Important Questions
Question 1.
What is adolescence period ?
Answer:
The age between 11 – 19 years is called adolescence.
Question 2.
When does growth in height stop ?
Answer:
Growth stops in boys at the age of 18, in girls at the age of 17.
Question 3.
What is reproduction ?
Answer:
Reproduction is the most important process for continuation of human race.
Question 4.
What is menarche ?
Answer:
The first menstrual cycle begins at adolescence and is termed as menarche.
Question 5.
What is menopause ?
Answer:
At 45 – 50 years of age, the menstrual cycle stops. This is termed as menopause.
Question 6.
When does menstruation occur ?
Answer:
Menstruation occurs once in about 28 – 30 days.
Question 7.
What is the legal age for marriage ?
Answer:
The legal age for marriage is 18 years for girls and 21 years for boys.
Question 8.
What is the function of endocrine glands ?
Answer:
They help in the regulation of the functioning of the human body.
Question 9.
What do endocrine glands release ?
Answer:
They release some chemicals (called hormones) directly into the blood.
Question 10.
What is the name of the male hormone ?
Answer:
The male hormone is ’Testosterone’.
Question 11.
What is the hormone begin to produce in girls ?
Answer:
In girls, the female hormone ’estrogen’ begins to produce in adolescence.
Question 12.
Which hormone controls emotions ?
Answer:
Adrenalin hormone secreted by Adrenal gland.
Question 13.
Why do the hunger levels are high in adolescents ?
Answer:
At this stage there is rapid growth and development.
Question 14.
How do young boys and girls keep the body fit and healthy ?
Answer:
All young boys and girls should take a walk, exercise and play outdoor games.
Question 15.
Why are endocrine glands called ductless glands ? Name them.
Answer:
Since they do not have specialized ducts, endocrine glands are called ductless glands.
Ex : Pituitary gland, Thyroid gland, Adrenal gland etc.
Question 16.
Why is it not good to eat junk foods ?
Answer:
Eating junk foods regularly may cause problems like obesity, mouth and stomach ulcerations, increase in blood sugar levels and blood pressure etc. So adolescents must say no to junk foods.
Question 17.
What are the factors involved in, to reach proper height ?
Answer:
It is influenced primarily by heredity and also environmental factors such as proper nourishment and regular exercise.
Question 18.
What is a balanced diet ?
Answer:
The diet which includes proteins,carbohydrates, fats and vitamins in require proportions is called a balanced diet.
Question 19.
What is target site ?
Answer:
Endocrine glands release hormones into the blood stream to reach a particular body called “target site”.
Question 20.
Give examples for “duct glands”.
Answer:
Sweat glands and salivary glands.
Question 21.
What is Adam’s apple ?
Answer:
The growing voice box in boys can be seen as a protruding part of the throat called Adam’s apple.
Question 22.
What is puberty ?
Answer:
The age in which human body undergoes several changes the boys and girls show their capability to reproduce.
Question 23.
Give two examples for secondary sexual characters in males.
Answer:
Change in voice, development of facial hair, increase in height etc ……..
Question 24.
Give two examples for secondary sexual characters in female.
Answer:
Development in breasts, growth of hair in arm pits, broadening of pubic region etc….
Question 25.
What is the master gland of endocrine system ?
Answer:
Pituitary gland is called master gland of endocrine system.
Question 26.
What are sex chromosomes ?
Answer:
The chromosomes which determine the sex of the unborn baby is called sex chromosomes.
Question 27.
Name the hormone secreted by pancreas.
Answer:
Insulin is the hormone secreted by pancreas.
Question 28.
What is metamorphosis ?
Answer:
The change from larva to adult through drastic changes is called metamorphosis.
Question 29.
Name the food sources of iron.
Answer:
Leafy vegetables, Jaggery, meat, citrus, Indian gooseberry (amla) are good sources of iron.
Question 30.
Name the virus that causes AIDS.
Answer:
HIV virus causes AIDS.
Question 31.
Which chromosome determines the sex of a male child among the X and Y chromosomes ?
Answer:
- All human beings have 23 pairs of chromosomes in the nuclei of their cells. Out of these 23 pairs, one pair of chromosomes are called Sex Chromosomes named X and Y.
- Female has two X chromosomes (XX) while a male has one X and one Y (XY) chromosomes.
- When a sperm containing X chromosome fertilises the
egg the zygote would have two X chromosomes (XX) and develop into a female child. - If the sperm containing Y chromosome to the egg (ovum) at fertilization the zygote would develop into a male child.
Hence the sex of a male child among X and Y, Y chromosome would determine the sex of a boy child.
Reaching the Age of Adolescence Extra Questions
Question 1.
What is menstrual cycle ? When does it begin ? What happens during this period ?
Answer:
Menstrual cycle :
- The cycle of changes takes place in the female reproductive system is called menstrual cycle. It occurs once in 28 to 30 days.
- It is termed as “menarche”.
- The first menstrual cycle begins at around 10 – 12 years of age and lasts till the age of 45 – 50 years.
Question 2.
What are endocrine glands ? What do they release ?
Answer:
Endocrine Glands :
- The glands which help in the regulation of the functioning of the human body are called endocrine glands.
- They release some chemicals directly into the blood which are called hormones.
Question 3.
How is physical exercise good for young boys and girls ?
Answer:
- Walking and playing in fresh air keeps the body fit and healthy.
- All young boys and girls should take a walk, exercise and play out door games.
- The physical activity leads to conditions of better health, sound sleep and there by mental peace.
- It promotes happiness in day to day life.
Question 4.
Write how child marriages cause damage to her health.
(OR)
Child marriage is a social evil. What problems would occur due to early marriage?
Answer:
- Teenage mothers are not prepared mentally for motherhood.
- Early marriage and motherhood cause health problems in the mother and child.
- It also curtails employment opportunities for the young woman and may cause mental agony as she is not ready for responsibilities of motherhood.
Question 5.
Why do adolescents get pimples on their face ?
Answer:
- Pimples are common in adolescents.
- It is because during adolescence the secretions of sweat and sebaceous glands become active. Because of their activity, boys and girls get pimples.
Question 6.
What do you suggest to your Mends to keep them clean and healthy ?
Answer:
I would suggest my friends.
- Take bath atleast twice in a day.
- Girls should take special care of cleanliness during the time of menstrual cycle.
- All parts of the body should be washed and cleaned everyday.
- If cleanliness is not maintained, there are chances of having fungal, bacterial and other wanted infections.
Question 7.
Write some slogans to create awareness among people about child marriages are social evil ?
Answer:
- Avoid child marriage – Protect childhood.
- Stop child marriage – stop child abuse.
- Childhood is not for motherhood.
- Let girls be girls but not brides.
Question 8.
Draw a neat sketch of Adam’s apple.
Answer:
Question 9.
Draw a neat diagram showing sex determination in humans.
Answer:
Question 10.
Draw a schematic diagram of menstrual cycle and reproduction.
Answer:
Question 11.
Write the modes of transmission of HIV.
Answer:
- The virus can pass on to a normal person from an infected person by sharing the syringes used for injecting drugs.
- It can also be transmitted to an infant from an infected mother through her milk.
- It can also be transmitted through sexual contact with a person infected with HIV.
Question 12.
Write some myths and taboos regarding bodily changes that adolescents experience.
Answer:
- Something is wrong if kids don’t grow taller soon after puberty hits.
- The mother is responsible for sex of her child.
- A girl should not be allowed to work in the kitchen during menstruation.
Extra Questions of Reaching the Age of Adolescence Class 8
Question 1.
Draw a neat and labelled diagram showing the position of endocrine glands in the human body.
Answer:
Question 2.
Complete the following table.
SI.No. | Name of the endocrine gland | Hormone secreted | Location | Disease caused |
1. | Pituitary gland | |||
2. | Thyroid | |||
3. | Pancreas | |||
4. | Adrenal |
Answer:
SI.No. | Name of the endocrine gland | Hormone secreted | Location | Disease caused |
1. | Pituitary gland | Pituitary hormone | Brain | Dwarfism |
2. | Thyroid | Thyroxine | Neck | Goitre |
3. | Pancreas | Insulin | Stomach | Diabetes |
4. | Adrenal | Adrenalin | over kidneys | Emotions are not controlled |
Question 3.
Mallika was 15 years old. Her parents decided to get her married. Is this correct ? Why?
Answer:
- The decision taken by the parents of Mallika is wrong.
- In our country the legal age for marriage is 18 years for girls and 21 years for boys.
- Teenage mothers are not prepared mentally or physically for motherhood.
- Early marriage and motherhood cause health problems for the mother and the child.
- It also curtails employment opportunities for the young woman and may cause mental agony as she is not ready for responsibilities of motherhood.
Question 4.
To know more details about given picture what questions do you ask your biology teacher ?
Answer:
- Name the structure shown in the above picture.
- How does this structure grow ?
- In whom do you observe this structure ?
- What changes do you observe in boys after the development of the above structure?
Question 5.
Write the impacts of drugs in adolescents.
Answer:
- Drugs are addictive, If you take them once, you feel like taking them again and again.
- They harm the body in long run.
- They ruin health and happiness.
- If anybody suggests that you will get relief if you take some drugs just say ‘no’ unless prescribed by the doctor.
Question 6.
Write a short note on balanced diet ?
Answer:
- The meals which include proteins, carbohydrates, fats and vitamins in requisite proportions.
- Our Indian meal of roti / rice, dal (pulses) and vegetables is a balanced meal.
- Milk is a balanced food in itself.
- Fruits also provide nourishment.
- For infants, mother’s milk provides all the nourishment that they need.
Question 7.
Abhijith observes the tadpole larvae of frog in a pond near his house. But he observed that even after 28 days, these larvae still remained as larvae. What might be the reason for that ?
Answer:
- Generally, tadpole larvae undergo metamorphosis and develop as adult frogs.
- In frog, it is controlled by thyroxine.
- Thyroxine production requires the presence of iodine in water.
- If the water in which the tadpoles are growing does not contain sufficient iodine the tadpole cannot become adults.
Question 8.
What are sex hormones ? Write the names of the glands that secrete them. Write a note on their effects.
Answer:
- Testosterone and Estrogen are called sex hormones.
- In males, testosterone is secreted by a pair of testes.
- It is helpful to produce sperm cells and brings secondary sexual characters in males.
- In females estrogen is secreted by a pair of ovaries.
- Estrogen regulates the release of ovum and menstruation.
Question 9.
What hygienic steps you would follow as an adolescent to keep yourself clean and healthy ?
Answer:
- I would take balanced diet daily.
- I would bath twice a day to avoid bacterial and fungal infections.
- I would prefer regular walking and cycling.
- I would play outdoor games regularly.
- I would say no to drugs, alcohol and tobacco.
- I would practice life skills, which can make me free from all hazards and become a good citizen.
Question 10.
What is the effect of sex hormones on the human body ?
Answer:
Testes secrete male hormone or testosterone and ovaries produce estrogen hormones. Sex hormones bring about changes in the body which are called the secondary sexual characters.
In boys the effects of hormones are :
- Growth of beard, moustaches and pubic hair.
- Voice becoming deep.
- Sudden increase in height.
- Development of muscles.
In girls, some changes takes place due to the effect of sex hormones :
- Pimples and acne problems.
- Growth of pubic hair.
- Development of breasts.
- Voice becoming high pitch type.
- Change of body shape.
Question 11.
What are the changes in the shape of the body of boys and girls at puberty ?
Answer:
At puberty the changes in shape of the body of boys are :
- the shoulders become broad and chest widen.
- the muscle development in boys will be more prominent than the girls.
- sudden increase in height as the bones of the arms and the legs elongate and make a person tall.
The changed in the shape of the body of girls are :
- the region below the waist becomes wider.
- development of breast.
- the girls tend to gain weight on their hips.
Question 12.
Nature prepares female human body to reproduce her generations. What do you think of it ?
Answer:
- In females the reproductive phase of life begins at puberty (10 to 12 years of age) and generally lasts till the age of (45 to 50).
- The ova begin to mature with the onset of puberty.
- One ovum matures and is released by one of the ovaries once in about 28 to 30 days.
- During this period the wall of the uterus becomes thick to receive the egg (ova).
- 5) In case if it is fertilized and begins to develop. This results pregnancy.
- The fertilised egg begins to divide embedded in the uterus for further development and leads to child’s birth.
- If fertilisation does not occur, the released egg and the thickened lining of the uterus along with its blood vessels are shed off.
- This causes bleeding in woman which is called menstrual cycle.
- Thus nature prepares the female human body to reproduce generation after generation to continue human life on the earth.
- This is the secret of nature and is nature’s wonderful phenomena.