Detailed explanations in West Bengal Board Class 10 Life Science Book Solutions Chapter 1C Response and Chemical Coordination in Animal Hormones offer valuable context and analysis.
WBBSE Class 10 Life Science Chapter 1C Question Answer – Response and Chemical Coordination in Animal Hormones
Short Answer Type Questions : 2 Marks
Question 1.
How does chemical coordination takes place in animals?
Answer:
Hormones act as chemical coordinators in animals. Hormone is the chemical messenger that regulates the physiological processes in living organisms. It is secreted by ductless glands into blood stream and reaches their target site.
Question 2.
Why is the use of iodised salt advised?
Answer:
It is advised to use iodised salt to prevent goitre (enlargement of the thyroid gland). Iodine is required for the proper functioning of thyroid. Iodine stimulates the thyroid gland to produce Thyroxine hormone. This hormone regulates carbohydrate, fat, and protein metabolism in our body.
Question 3.
Name the hormone secreted by an endocrine gland during emergency. Vame the gland which secretes this hormone.
Answer:
Adrenaline hormone is secreted by the adrenal glands. It helps to regulate heart beat, blood pressure, metabolism in the time of stress or emergency to cope up with the situation.
Question 4.
Which hormone is injected to a diabetic patient and why?
Answer:
Hormone is released by pancreas gland which regulates the blood sugar level. In diabetic patients, pancreas has stopped releasing insulin hormone. If it is not secreted in proper amount, the sugar level in the blood rises causing many harmful effects. Due to the reason diabetic patients are treated by giving injection of insulin.
Question 5.
How does our body respond when adrenaline is secreted into the bood?
Answer:
During emergency situations, adrenaline hormone is released to blood stream in large quantitie. It increases the heartbeat and hence supplies more Oxygen to the muscles. The increase in breathing rate also increases due to contractions of diaphragm and rib muscles. It raises the blood pressure and thus enables the body to cope up with any stress or emergency.
Question 6.
Which endocrine gland is called master gland? Why?
Answer:
Pituitary gland (pea shape, present in mid-brain) is considered as master endocrine gland. It is said so because it controls almost all other endocrine glands.
Question 7.
Why is pancreas a dual gland?
Answer:
Pancreas is a dual gland because it acts as both endocrine and exocrine gland. As endocrine it secretes hormones like insulin, glucagon. As an exocrine glands, it releases enzymes like Trypsin, Lypase, Amylase etc.
Question 8.
How does our body maintain blood sugar level?
Answer:
The timing and amount of hormone released are regulated by feedback mechanisms. When the sugar levels in blood rise, they are detected by the cells of the pancreas which respond by producing more insulin. As the blood sugar level falls, insulin secretion is reduced.
Question 9.
Where Islet of langerhans is found? Name the secretion of different kind of cells of Islets?
Answer:
Islet of Langerhans is found in the endocrine cells of pancreas.
The secretion of different kinds of cells of Islets are :
- α cells – Glucagon
- β cells – Insulin
- δ cells – Somatostation
Question 10.
Define a neuron and a ganglion?
Answer:
The functional and structural unit of kindey is called neuron.
Ganglion : The cell body of large no. of nerve cells outside the CNS together form a gland like structure is known as ganglion.
Question 11.
Name one mixed endocrine gland. What are their secretion?
Answer:
Pancreas is a mixed endocrine gland. Their secretions from exocrine and endocrine are enzyms and hormones respectively.
Question 12.
What is an endocrine gland? What is the name of its secretion?
Answer:
Endocrine gland is gland from which hormones are secreted and passing through blood and lymph to the all body parts.
Hormones are secreted from endocrine gland.
Question 13.
What are the functions of tropic hormone?
Answer:
Tropic hormone : They are the hormones which are secreted from the glands and control the growth and secretion of another gland.
Functions : It controls the growth and secretion of another gland.
Question 14.
What is meant by flight-or-flight response?
Answer:
The epinephrine and norepinephrine hormones help to increase the flow of blood to the brain and muscles to inprove the ‘flight-or-flight’ response to stress.
Question 15.
State the name and one function of the hormone secreted from Islets of Langerhan’s?
The endocrine cells of pancreas is called Islets of Langerhans:
Answer:
Function (i) Glucogenolysis – Split liver glycogen and convert into glucose.
Question 16.
What is endocrine gland? Give an example.
Answer:
In higher animals including human hormones are secreted by ductless glands known as endocrine glands. Eg-Human.
Question 17.
What is diabetes mellitus?
Answer:
Diabetes mellitus is achronic, lifelong condition that affects body’s ability to use the energy found in food.
Question 18.
From where are thyroid stimulating hormone and Thyrovine secreted?
Answer:
Thyroxin is secreted from the hormone secreted by thyroid gland.
Question 19.
Write three major differences between hormone and enzyme.
Answer:
The differences between hormone and enzyme are :
| Hormone | Enzyme |
| i. Hormone is produced by ductless endocrine glands. | i. Enzyme is produced by ducted endocrine glands. |
| ii. Transmitted through lymph and blood vessels. | ii. Transmitted through ducts. |
Question 20.
What is the full form of IH? State one function of this hormone.
Answer:
The full form of LH is Luteinising Hormone.
One function of Luteinising Hormone is : (i) Luteinising Hormone stimulates the secrete of Progesterone from corpus luteum.
Question 21.
Why edible salt should be iodised. Sate one functional difference between Auxin and Thyroxine.
Answer:
Edible salt should be iodised because :
- Ocean salt is with iodine but iodine is destroyed during the salt preparation.
- Iodine is added to the salt.
- The development of thyroid gland and secretion of T3, T4 increase if iodine is taken.
Question 22.
Which hormone prevents gluconeogenesis from protein and fat?
Answer:
Insulin prevents gluconeogenesis from protein and fat.
Question 23.
Write the name of two tropic hormones.
Answer:
Two tropic hormones are :
(i) Adreno Corticotropic Hormone
(ii) Somato Tropic Hormone.
Question 24.
Name an animal hormone which is lipid base.
Answer:
Thyroxine.
Question 25.
Give a flow chart for feedback mechanism of Thyroxine and TSH
Answer:
Long Answer Type Questions : 5 Marks
Question 1.
Why do humans need endocrinal system?
Answer:
Nervous system in human body works to communicate using nerve impulses which are formed of electrical impulses. Electrical impulses are an excellent means of communication in human body but they have following limitations.
(a) They reach only those cells that are connected by nervous tissue, not each and every cell in the animal body.
(b) Cells cannot continually create and transmit electrical impulses. Once an electrical impulse is generated in a cell and transmitted, the cell will take some time to reset its mechanisms before it can generate and transmit a new impulse.
Due to above said limitations most multicellular organisms use another means of communication between cells namely chemical communication i.e. hormone of endocrine system. It is slower than nerve cells, but potentially reach all cells of the body.
Question 2.
Point out two relevant differences between plant hormones and animal hormones.
Answer:
| Plant hormones | Animal hormones |
| i. Plant hormones are secreted from immature meristematic tissue. | i. Animal hormones are secreted from endocrine glands. |
| ii. Plant hormones are acidic or alkaline in nature. | ii. Animal hormones are protein or steroid in nature. |
Question 3.
Write two differences between exocrine and endocrine glands. Why is pituitary gland called “master gland”?
Answer:
The two differences between exocrine and endocrine glands are –
| Exocrine Glands | Endocrine glands |
| i. The exocrine glands possess ducts. | i. The endocrine glands do not possess ducts. |
| ii. The exocrine glands secrete their secretion either on the surface or a particular region by means of ducts. e.g. salivary glands, mammary glands. | ii. The endocrine glands secrete their secretion through blood one lymph vessels. e.g : pituitary gland, thyroid gland. |
Question 4.
Why is hormone called a chemical coordinator?
Answer:
Hormone is called a chemical coordinator because :
- Hormone transmits chemical message from source organ to the target tissue and chemically coordinate cells, tissues.
- Hormones secreted from endocrine glands contain chemicals controlled by gene.
- Hormones coordinate different body organs by means of chemical messages.
Question 5.
Write the sources and functions of Oestrogen and Progesterone.
Answer:
| Hormone | Source | Functions (one) |
| 1. Oestrogen : | i. Graafian follicles ii. Chorionic villi of placenta iii. Adrenal cortical gland |
i. In pregnancy it induces enlargement of uterus and breasts. |
| 2. Progesterone : | i. Corpus luteum ii. Chorionic villi of placenta iii. Adrenal cortical gland. |
i. In contrals growth and maintenance of endometrium of uterus. |
Question 6.
Name the hormone secreted from Leydig cells and the hormone that activates the Leydig cells. Write any two functions of Oestrogen.
Answer:
The hormone which is secreted from Leydig cells is Testosterone, and the hormone that activates the Leydig cells is intestitial Cell Stimulating Hormone.
The two functions of Oestrogen :
(i) It controls the formation and maintenance of secondary sex characters.
(ii) In pregnancy, it induces enlargement of uterus and breasts.
Question 7.
The urine becomes hypotonic or hypertonic due to the influence of which hormone and how?
Answer:
The urine becomes hypertonic or hypotonic due to the influence of Adrenaline hormone.
By increasing or decreasing the renal circulation, the Adrenaline hormone causes the urine to be hypertonic or hypotonic.
Question 8.
Dite the influence of which hormones dwarfism. myxoedema, diabetes mellitus and acromegally occur? Vame two hormones that increase BMR.
Answer:
Dwarfism occurs due to the influence of somatotropic Hormone (deficiency)
- Mvoedema occurs due to the influence of Thyroxine Hormone (hyposecretion)
- Diabetes mellitus occurs due to the influence of Insulin hormone.
- Acromegally occurs due to the influence of somatotropic Hormone (Excessive secretion)
The two hormones that increase BMR are Thyroxine hormone and Adrenaline hormone.
Question 9.
Nention the places of secretion and one function of each of STH, GTH and Ndrenaline. Write any two differences between Cretinism and Dwarfism.
Answer:
| Hormone | Source | Functions (one) |
| i. STH | Anterior Pituitary | i. STH helps in skeletal growth by stimulating multiplication of ephiphyseal cartilage present at the tip of long bones. |
| ii. GTH | Anterior Pituitary | ii. In females, it causes the growth of ovaries. |
| iii. Adrenaline | Adrenal Medulla | iii. Contraction and relaxation of heart, heart beats and cardiac outputs are increased by the action of adrenaline. |
The two differences between Cretinism and Dwarfism :
| Cretinism | Dwarfism |
| i. Cretinism is caused due to decreased secretion of thyroxine during childhood. | i. Dwarfism is caused due to the deficiency of somatotropic hormone during childhood. |
| ii. Congenital abnormality of thyroid gland. | ii. Abnormal secretion of pituitary gland. |
Question 10.
Mention the source and one function of each of the following : Adrenaline. Thyroxine, Testosterone.
Answer:
| Hormone | Source | Function |
| Adrenaline | Adrenal Medulla | i. Contraction and relaxation of heart, heart beats and cardiac output are increased by the action of Adrenaline. |
| Thyroxine | Thyroid gland | i. Thyroxine helps skeletal; muscular, sexual, mental growth. |
| Testosterone | Interstitial cells of leydig | i. At the time of puberty it causes the development of male secondary sex organs-seminal vesciles, penis, scrotum. |
Question 11.
State three characteristics of hormones.
Answer:
The three characteristics of hormones are :
- Hormones are complex organic compounds of low molecular weight and secreted from cells and glands.
- Hormones are protein or steriod in nature and never stored in any other place for future use except the secreting glands or tissues.
- Most hormones are highly soluble in nature and are conducted easily through cell sap or blood stream.
Question 12.
State the site of secretion and function of Insulin and Glucagon. In which endocrine disease BMR is low?
Answer:
Insulin :
Site of secretion : B cells of Islet of Langerhans of the pancreas.
Function :
- Insulin increases the activity of hexokinase enzyme in the cells and thus increases the oxidation of glucose in the cell.
- Insulin stimulates the formation and storage of glycogen in the liver and muscle taking glucose from blood.
- The process of formation of glucose from protein, fats (gluconeogenesis)
Question 13.
What is emergency hormone? Mention its source. Why is it named so?
Answer:
Adrenaline is known as emergency hormone.
Source : The Adrenal Medulla secretes Ardrenaline.
Adrenaline is named emergency hormone because, the rate of secretion from Adrenal Medulla increases during emergent conditions such as-fear, anxiety, emotional conditions to cause widespread responses by which a subject is able to fight out the situation successfully.
Question 14.
State one function of each Oxytocin, Oestrogen, Testosterone, Secretin, Thyroxine.
Answer:
Function of Oxytocin : Oxytocin plays an important role in lactation and stimulates the contraction of pregnant uterus.
Function of Oestrogen : In pregnancy, it induces the enlargement of uterus and breasts.
Function of Testosterone : At the time of puberty, it causes the development of secondary sex organs-penis, seminal vesciles, scrotum.
Secretin : Stimulates the secretion of intestinal gland present in the inner wall of intestine.
Thyroxine : It increases the utilisation of O2 and formation of CO2 thus increases the rate and depth of respiration.
Question 15.
List the function of each of the following :
Answer:
(a) Growth hormone : Growth hormone helps in skeletal growth by stimulating multiplication of epiphyseal cartilage present at the tips of the long bones.
(b) Prolactin : It stimulates the development of mammary glands during pregnancy and following childbirth, the production of milk is originated by them.
(c) Follicle Stimulating Hormone : In females it helps in the maturation of immature follicles into mature follicles called Graaffian follicles.
Question 16.
Mention one functional similarity and two functional dissimilarities between nervous system and hormones in animal body.
Answer:
| Nervous System | Hormones |
| i. Nerve acts as a coordinator in animal body. | i. Hormone acts as a coordinator in animal body. |
Functional similarity between nervous system and hormones :
| Nervous System | Hormones |
| i. Nerve acts as a physical coordinator in animal body. | i. Hormone acts as a chemical coordinator in all living bodies. |
| ii. Action of nervous system is very faster. | ii. Action of hormone is slow. |
Question 17.
Explain the source and function of Progesterone and Testosterone in man.
Answer:
Question 18.
Why are gonads called mixed gland?
Answer:
The gonads are called mixed gland because :
(i) It has both exocrine and endocrine secretion.
(ii) It has metabolic and cytogenic activities.
Exocrine secretion : The gonads secrete sucrose, fructose and maltose.
Endocrinal secretion : The gonads secrete hormones like Testosterone by testis and Progestron, Oestrogen by Overy.
Question 19.
State the full name of ACTH, its site of secretion, function.
Answer:
The full name of ACTH is Adreno Cortico Tropic Hormone.
Site of Secretion of ACTH : Anterior Pituitary.
Functions of ACTH : (i) It stimulates the growth of adrenal cortex (ii) It stimulates the secretion of hormone from adrenal cortex.
Question 20.
State the name and two functions of the hormones secreted from Islets of Langerhans.
Answer:
Insulin is secreted from the β cells of Islets of langerhans.
Furretions of Insulin :
(i) Insulin increases the activity of the hexokinase enzyme in the cells and thus increases oxidation of glucose in the cell.
(ii) The process of formation of glucose from protein, fats, carbohydrate sources (gluoneogenesis) is inhibited by Insulin.
Question 21.
Name the antidiabetogenic hormone. Which hormone is called calorigenic hormone and why? What cause acromegally?
Answer:
The anidiabetogenic hormone is Insulin.
(i) Thyroxine hormone is called calorigenic hormone because it increases oxygen uptake and metabolism by the tissues and thus accelerates energy production i.e. B.M.R.
(ii) As Thyroxine increases the body temperature, it is known as calorigenic hormone.
Multiple Choice Questions : 1 Mark
Question 1.
Which of the following hormones is released by thyroid?
(a) Insulin
(b) Thyroxine
(c) Trypsin
(d) Pepsin
Answer:
(b) Thyroxine
Question 2.
Which of the following hormones contains iodine?
(a) Adrenaline
(b) Testosterone
(c) Thyroxine
(D) Insulin
Answer:
(c) Thyroxine
Question 3.
Which of the following is a mixed gland?
(a) Pancreas
(b) Silvery gland
(c) Liver
(d) Thyroid gland.
Answer:
(a) Pancreas
Question 4.
_______ is not secreted by an endocrine gland.
(a) Insulin
(b) Thyroxine
(c) Pepsin
(d) Adrenaline
Answer:
(c) Pepsin
Question 5.
From which endocrine gland is ACTH secreted?
(a) Adrenal
(b) Isletes of Langerhans
(c) Thyroid
(d) Insulin
Answer:
(d) Insulin
Question 6.
Which of the following hormone is a local hormone?
(a) Thyroxine
(b) Insulin
(c) Testosterone
(d) Adrenaline
Answer:
(c) Testosterone
Question 7.
Name the hormone that regulate the metamorphosis of tadpole larvae
(a) Thyroxine
(b) Insulin
(c) ADH
(d) Adrenaline
Answer:
(a) Thyroxine
Question 8.
Secretion of thyroid gland is controlled by
(a) TSH
(b) STH
(c) ACTH
(d) GTH
Answer:
(a) TSH
Question 9.
Dwarfism is due to the deficiency of
(a) ACTH
(b) Insulin
(c) GTH
(d) STH
Answer:
(d) STH
Question 10.
Which of the following endocrine gland secretes TSH
(a) Thyroid
(b) Testis
(c) Adrenal
(d) Pituitary
Answer:
(d) Pituitary
Question 11.
Which of the following endocrine gland secretes STH
(a) Thyroid
(b) Adrenal
(c) Testis
(d) Pituitary
Answer:
(d) Pituitary
Very Short Answer Type Questions : 1 Mark
Question 1.
Who coined the term hormone?
Answer:
Bayliss and Starling coined the term hormone. Both of them discovered the peptide hormone called secretin in human intestine.
Question 2.
Where are adrenal glands located?
Answer:
Adrenal glands are like caps just above the kidneys.
Question 3.
What is hyperglycemia?
Answer:
Hyperglycemia refers to high sugar level in blood. In general diabetic patients has hyperglycemia due to insufficient release of insulin hormone.
Question 4.
Where is thyroid gland located?
Answer:
Thyroid gland is situated in front of the neck below larynx.
Question 5.
From which gland is GHT secreted?
Answer:
The basophil cells of anterior pituitary.
Question 6.
Give the full name of STH?
Answer:
Somatotropic Hormone.
Question 7.
From which gland is pholactin secreted?
Answer:
Mammary gland.
Question 8.
Write the full form of ADH.
Answer:
Antidiuretic hormone.
Question 9.
Write one symptom of dwarfism.
Answer:
Below average growth, although body proportion will be normal.
Question 10.
TRH is produced from
Answer:
Thyroid gland.
Question 11.
Diabetes insipidus is caused by hyposecretion of
Answer:
ADH
Question 12.
Milk releasing hormone is
Answer:
Prolactin/Lactrotrophic hormone.
Question 13.
Which hormone is secreted from Adrenal gland?
Answer:
Adrenaline, Non-Adrenaline.
Question 14.
From where is testosterone secreted?
Answer:
Intorstitial cells of lydiag of Testes in male human.
Question 15.
Which is the synthetic hormone?
Answer:
Auxin.
Question 16.
АCTH is secreted from
Answer:
Pituitary.
Question 17.
Diabetes insipidus is caused by the deficiency of
Answer:
Insulin.
Question 18.
Glucagon is secreted from
Answer:
Islets of Langerhans.
Question 19.
Name the gland from where tropic hormones are produced
Answer:
Thyroid gland.
Question 20.
Which gland produced TSH hormone?
Answer:
Pituitary gland.
Question 21.
Enlargement of thyroid is the symptom of the disease
Answer:
Goiter.
Question 22.
Which one is mixed gland?
Answer:
Pancreas.
Question 23.
FSH is secreted from
Answer:
Graafian follicles.
Question 24.
Name the master gland of human body.
Answer:
The master gland of human body is pituitary gland.
Question 25.
Give an example of local hormone.
Answer:
An example of Local hormone is Secretin.
Question 26.
What is the source of insulin?
Answer:
The source of insulin is B cell of the Islets of langerhans of pancreas.
Question 27.
What is the source of Progesterone?
Answer:
Progesterone is secreted from corpus luteum of ovary.
Question 28.
List two symptons of myxoedema.
Answer:
Two symptoms of myxoedema are :
(i) Low Basal Metabolic Rate
(ii) Low Body temperature.
Question 29.
From where is Adrenaline secreted?
Answer:
Adrenaline is secreted from adrenal medulla.
Question 30.
Name one calorigenic hormone.
Answer:
One calorigenic hormone is Thyroxine.
Question 31.
Name the hormone secreted from Graafian Follicle of ovary in adult female.
Answer:
The hormone which is secreted from the Graafian Follicle of ovary in adult female is oestrogen.
Question 32.
Why is pancreas called a mixed gland?
Answer:
Pancreas is a mixed gland because it contains both exocrine and endocrine parts. Pancreas produces hormones besides having metabolic and cytogenic activities.
Question 33.
Which hormone helps in elongation of internodes of plant stem?
Answer:
Auxin helps in the elongation of internodes of plant stem.
Question 34.
Iodine is essential for which animal hormone?
Answer:
Iodine is essential for thyroid hormone (Thyroxine)
Question 35.
Which hormone helps in the formation of placenta in women?
Answer:
Oxytocin helps in the formation of placenta in women.
Question 36.
Name two hormones secreted from posterior pituitary. Give the full form of ICSH.
Answer:
The two hormones which are secreted from posterior pituitary are :
(i) Antidiuretic hormone or Vasopressin
(ii)-Oxytocin.
The Full from of ICSH – Interstitial Cell Stimulation Hormone.
Question 37.
Why does hypofunction of thyroid cause anaemia?
Answer:
Thyroid hormone helps in the development of R.B.C. That is why the hypofunction of thyroid causes aneamia.
Question 38.
Which hormone helps in the production of sperms?
Answer:
Follicle Stimulating Hormone helps in the production of sperms.
Question 39.
Write the position of pituitary gland in human.
Answer:
The pituitary gland is located under the brain, within the small bony cavity, sella turcica of the sphenoid bone. Inside bony cavity, sella turcica and hanged with infundibulum of anterior part of human brain.
Question 40.
State the effects of-
Answer:
(a) Hypofunction of STH in children : Causes Dwarfism.
(b) Hyperfunction of STH in children : Causes Gigantism.
(c) Hyposecretion of Insulin : Cauces Diabetes mellitus.
Question 41.
From which gland is the Testosterone hormone secreted?
Ins.
Testosterone is secreted from the Testis.