The Class 8 biology chapter 5- Endocrine System and Adolescence, deal with how a body changes from being a kid to a grown-up. It briefs about the endocrine system and how its effect during adolescence. Go through the chapter thoroughly and solve the questions given in Selina’s textbook. Once done with solving them, evaluate your performance by comparing it with the ICSE Selina Class 8 Biology Chapter 5- Endocrine System and Adolescence Solutions by Flash Education.
Book Name | : Concise (Selina) |
Subject | : Biology |
Class | : 8 |
Publisher | : Selina |
Chapter Name | : Endocrine System and Adolescence |
Multiple Choice Questions:
1. Put a tick mark against the correct alternative in the following statements:
Question 1 :
Cortisone hormone is secreted by:
(a) Medulla of adrenal
(b) Cortex of adrenal
(c) Pancreas
(d) Thyroid
Answer :
(b) Cortex of the adrenal
Question 2 :
Which one of the following hormones stimulates the breakdown of glycogen in the liver into glucose:
(a) Insulin
(b) Adrenaline
(c) Glucagon
(d) Thyroxine
Answer :
(c) Glucagon
Question 3 :
Which one of the following hormones converts excess of glucose into glycogen:
(a) Glucagon
(b) Thyroxine
(c) Insulin
(d) Adrenaline
Answer :
(c) Insulin
Question 4 :
Which one of the following glands is also called master gland:
(a) Pituitary gland
(b) Adrenal gland
(c) Thyroid gland
(d) Ovary
Answer :
(a) Pituitary gland
Question 5 :
The emergency hormone to face danger or to fight is secreted by:
(a) Islets of Langerhans
(b) Adrenal cortex
(c) Pituitary
(d) Adrenal medulla
Answer:
(d) Adrenal medulla
Question 6 :
Which one of the following endocrine glands produce its hormone in large quantities as a result of emotional stimulation?
(a) Thyroid
(b) Islets of Langerhans
(c) Adrenal medulla
(d) Adrenal cortex
Answer:
(c) Adrenal medulla
The adrenal medulla produces its hormone in large quantities as a result of emotional stimulation.
Question 7 :
In humans, increased thyroxine production results in (tick the correct Solution):
(a) Increased metabolism
(b) Decreased metabolism
(c) Dwarfism
(d) Cretinism
Answer :
1. Increased metabolism
Question 1 :
What is a hormone?
Answer :
The secretions of the endocrine glands are called Hormones, they are mixed directly into the blood and are transferred to the target organs.
Question 2 :
In the table given below, fill in the blanks by naming endocrine glands, the hormones they secrete, and the function they perform, in a normal person.
Answer :
S.No | Name of the gland | produced | Function |
1. | Thyroid | Thyroxine | Control of the metabolic rate |
2. | Pancreas | Insulin | Regulation of sugar in the blood |
3. | Adrenal | Adrenaline and cortisone | Preparing the body for action |
4. | Pituitary | (i) Growth hormone
(ii) Thyroid stimulating hormone |
(i) for growth
(ii) stimulates the thyroid gland to secrete thyroxine |
Question 3 :
Match the items in Column A with those in Column B.
Column A Column B
(a) Cretinism (i) Insufficient insulin in the blood.
(b) Diabetes mellitus (ii) Over secretion of thyroxine
(c) Increased metabolic rate (iii) Under development
(d) Simple goitre (iv) Insufficient iodine in
(e) Growth hormone (v) Insufficient insulin in the blood.
Answer :
Column A Column B
(a) Cretinism (iii) Under development
(b) Diabetes mellitus (i) Insufficient insulin in the blood.
(c) Increased metabolic rate (ii) Over secretion of thyroxine
(d) Simple goitre (iv) Insufficient iodine in
(e) Growth hormone (v) Insufficient insulin in the blood.
Question 4 :
Name the source and the function of each of the following hormones:
Hormone | Source | Function |
(a) Glucagon | ||
(b) Thyroxine | ||
(c) Adrenaline | ||
(d) Insulin | ||
(e) Cortisone |
Answer :
Hormone | Source | Function |
(a) Glucagon | Pancreas | Glycogen is broken down to glucose. Raises sugar in the blood. |
(b) Thyroxine | Thyroid gland | Control of the metabolic rate |
(c) Adrenaline | Adrenal gland | Prepare the body to face emergency, stress |
(d) Insulin | Pancreas | Regulation of sugar in the blood |
(e)Cortisone | Adrenal cortex | Regulates carbohydrate metabolism. Its deficiency causes Addison’s disease |
Question 5 :
What is the difference between an exocrine gland and an endocrine gland?
Answer :
Exocrine glands are salivary glands, pancreas, etc. they send their secretions through ducts directly to the target or On the other hand, the endocrine glands are ductless glands.
Their secretions are called hormones, which are poured directly into the blood and are thus carried to the target organs.
Question 6 :
Why is a pituitary gland called “master gland”?
Answer :
A “master gland” that produces hormones that control other glands and many body functions including growth (growth hormone, Thyroid, and Gonad stimulating hormone) is called the pituitary gland.
Question 7 :
Briefly write about the importance of physical hygiene during adolescence.
Answer :
Physical hygiene also named Personal hygiene plays a crucial role in maintaining health during adolescence. Teenagers should follow the below-mentioned activities to promote their health:
1. Proper and Safe Food: The stage of rapid growth and development is called adolescence. Hence, a teenager should take proper care of their diet. They should take a properly balanced diet that provides proteins, carbohydrates, fats, minerals, and vitamins. They should take freshly prepared food and avoid stale food. They should take milk, fruits, and fresh vegetables.
2. Proper lifestyle: Regular Exercise and sleep are necessary for maintaining good health. A teenager should avoid long hours of continuous table work and television watching. A teenager should not consume alcohol, drugs, or smoke.
3. Cleanliness: Teenagers should take baths regularly. Before and after having meals they should always wash their hands. Brushing up teeth after every meal. They should always change and wear washed clothes, especially undergarments. Regular toilet habits should be adopted for maintaining good health. Must keep their feet cleaned and protected. Injuries due to bacteria like tetanus, hookworms, and insects may be issued if a barefoot walk is undertaken. They must wash and comb their hair regularly. All body parts must be washed and cleaned every day. If cleanliness is not maintained there may occur chances of catching a bacterial infection. Girls should take special care of cleanliness during the time of the menstrual period.
4. Physical Exercise: In order to keep the body fit and healthy, teenagers should walk, exercise and play outdoor games regularly in the fresh air. Playing Outdoor games reduces the stress and strain of adolescence.
Question 8 :
Briefly discuss any four activities which can be practiced to overcome stress.
Solution:
Stress is a state of mental or emotional strain and in simple terms, it is called tension.
The stress can be controlled or reduced by following the below-mentioned steps:
1. Yoga: Physical poses, controlled breathing, and meditation or relaxation is a combined mind practice called yoga. Yoga helps in reducing steps by:
(a) Increasing Flexibility
(b) Increasing muscle strength and tone.
(c) Improving respiration, energy, and vitality.
2. Exercise: Exercising or Running for 30 to 45 minutes at least three times a week reduce stress and keeps the body much healthier.
3. Proper sleep schedule: Improving your sleep schedule also helps in reducing stress.
4. Reading is a great way to calm your mind and gain more knowledge.
5. Practice Hobbies of your interest: One should keep practicing their hobbies as it helps in reducing stress. Enjoy playing the guitar, piano or listening to music, or doing riddles.