Chapter – 1 : Control and Coordination in living organisms | Chapter Solution Class 10

Book Name	: Life Science And Environment
Subject	: Life Science
Class	: 10 (Madhyamik)
Publisher	: Santra Publisher Pvt. Ltd
Unit Name	: Control and coordination of living organisms

Multiple Choice Questions

Question 1

Who discovered the sensitivity of plants?

1. Pavlov.
2. J. C. Bose.
3. Darwin.
4. Went

Answer

J. C. Bose.

Explanation

Jagadish Chandra Bose was an Indian physicist and biophysicist who is considered the father of plant physiology. He was the first to discover that plants have a nervous system and can respond to stimuli in a similar way to animals.

Question 2

Which type of movement shows in Volvox?

1. Phototropic.
2. Thermonastic.
3. Prototactic.
4. Geotropic

Answer

Prototactic

Question 3

Chemonastic movement is found in

1. Drosera.
2. Sunflowers.
3. Oxalis.
4. Mimosa

Answer

Drosera

Question 4

Which type of movement is found in Tulips?

1. Seismonasticb.
2. Hydrotropicc.
3. Thermonasticd.
4. Photonastic

Answer

Thermonastic

Explanation

Thermonastic movement is the movement of an organism in response to changes in temperature. Tulips open their flowers in warm weather and close their flowers in cold weather.

Question 5

Which is the natural auxin?

1. 2, -Db
2. NAAE
3. IAA
4. IPA

Answer

IAA

Explanation

IAA stands for indole-3-acetic acid, and it is the most common natural auxin found in plants. It is a plant hormone that is responsible for a variety of growth and development processes, including cell elongation, apical dominance, and root formation.

Question 6

Seed germination is induced by which hormone?

1. Gibberellic acid
2. Auxin
3. Cytokinins
4. ABA

Answer

Gibberellic acid

Explanation

Gibberellic acid (GA) is a plant hormone that is responsible for a variety of growth and development processes, including seed germination.

Question 7

Which hormone delay leaf senescence?

1. Auxin.
2. Gibberellins.
3. Cytokinins.
4. IAA

Answer

Cytokinins

Explanation

Cytokinins are plant hormones that are responsible for a variety of growth and development processes, including cell division, delay of leaf senescence, and apical dominance.

Question 8

Which is the synthetic hormone?

1. IBA
2. ABA
3. Auxind.
4. Cytokinin

Answer

IBA

Explanation

IBA stands for indole-3-butyric acid, and it is a synthetic auxin that is used to promote root growth. It is a colourless, odourless solid that is soluble in water and organic solvents.

Question 9

ACTH is secreted from.

1. Pituitary.
2. Thyroid.
3. Adrenald.
4. Gonads

Answer

Pituitary

Explanation

ACTH stands for adrenocorticotropic hormone, and it is a hormone that is produced by the pituitary gland. The pituitary gland is a small gland that is located at the base of the brain.

Question 10

Diabetes insipidus is caused by the deficiency of

1. Insulin.
2. GTH
3. Thyroxine.
4. ADH

Answer

ADH

Explanation

Diabetes insipidus is a condition in which the body does not produce enough of the hormone antidiuretic hormone (ADH), also known as vasopressin.

Question 11

Thyroxin is secreted from

1. Thyroid.
2. Pituitary.
3. Gonadd.
4. Pancreas

Answer

Thyroid

Explanation

Thyroxine is a hormone that is produced by the thyroid gland. The thyroid gland is a small, butterfly-shaped gland that is located in the neck. Thyroxine is responsible for regulating metabolism, growth, and development.

Question 12

Which of the following is associated with Schwann cells?

1. Dendrite
2. Axon
3. Cell body
4. Synapse

Answer

axon

Explanation

Schwann cells are glial cells that are found in the peripheral nervous system (PNS). They wrap around axons to form myelin sheaths, which insulate the axons and help to speed up the conduction of nerve impulses.

Question 13

Enlargement of thyroid is the symptom a of the disease

1. Dwarfism
2. Goitre
3. Diabetes Mellitus
4. Acromegaly

Answer

Goitre

Explanation

Goitre is a medical term for an enlarged thyroid gland. It can be caused by a number of factors, including iodine deficiency, autoimmune disorders, and certain medications.

Question 14

Where is the node of Ranvier located?

1. Myelinated axon
2. Dendrite
3. Synapse
4. Cell body

Answer

Myelinated axon

Explanation

Myelin is a fatty sheath that surrounds axons in the peripheral nervous system (PNS). It helps to insulate the axons and speed up the conduction of nerve impulses. The nodes of Ranvier are short gaps in the myelin sheath.

Question 15

Where is the pupil situated?

1. Retina
2. Lens
3. Iris
4. Cornea

Answer

Iris

Explanation

The iris is the coloured part of the eye. It is a muscular diaphragm that controls the amount of light that enters the eye. The pupil is the opening in the centre of the iris. It is surrounded by the iris, which is made up of smooth muscle fibres. These muscles contract and relax to adjust the size of the pupil.

Question 16

The balance organ of the brain is

1. Cerebrum
2. Cerebellum
3. Hypothalamus
4. Pons

Answer

Cerebellum.

Explanation

The cerebellum is located at the back of the brain, below the cerebrum. It is responsible for coordinating movement, balance, and posture. The cerebellum receives information from the inner ear, eyes, and muscles. It then uses this information to make adjustments to the body’s movements.

Question 17

Cerebrum is the part of

1. Forebrain
2. Hindbrain
3. Midbrain
4. Spinal cord

Answer

Forebrain

Explanation

The cerebrum is the largest part of the brain and is responsible for higher-order functions, such as thinking, planning, and language. It is divided into two hemispheres, the left and right hemispheres.

Question 18

Where is an image formed in the eye?

1. Sclera
2. Retina
3. Lens
4. Cornea

Answer

Retina

Explanation

The retina is a light-sensitive tissue that lines the back of the eye. It contains photoreceptor cells that convert light into electrical signals. These signals are then sent to the brain, where they are interpreted as images.

Question 19

Which one is a mixed gland?

1. Pituitary
2. Liver
3. Tear gland
4. Thyroid

Answer

Pancreas

Explanation

A mixed gland is a gland that secretes both hormones and other substances, such as digestive enzymes.

Question 20

The surface area of wings is increased in birds with the help of

1. Pectoralis major
2. Pectoralis minor
3. Remiges
4. Rectrices

Answer

Remiges

Explanation

Remiges are the primary feathers that extend along the leading and trailing edges of the wings. They are responsible for providing lift and thrust during flight.

Fill in the Blanks

Question 1

In ____ ciliary movement is observed.

Answer

Paramoecium

Question 2

____ discovered the sensitivity of plants.

Answer

Acharya Jagadish Chandra Bose

Question 3

Production of seedless fruit is called ____.

Answer

parthenocarpy

Question 4

_____ is the long process of the nerve cell body.

Answer

Axon

Question 5

____ helps to reduce blood sugar.

Answer

Insulin

Mention True or False

Question 1

STH is a proteinaceous animal hormone.

Answer

True

Explanation

STH stands for somatotropin or growth hormone. It is a proteinaceous hormone that is produced by the pituitary gland. It is essential for growth and development in humans and other animals.

Question 2

Cytokinin is present in the liquid endosperm of coconut.

Answer

True

Explanation

Cytokinins are plant hormones that are involved in a variety of processes, including cell division, delay of leaf senescence, and apical dominance. They are present in the liquid endosperm of coconut, which is the white, jelly-like substance that surrounds the embryo.

Question 3

Triceps is a kind of extensor muscle.

Answer

True

Explanation

The triceps is a muscle in the back of the upper arm. It is responsible for extending the elbow joint. When the triceps contracts, it straightens the arm.

Question 4

Closure of leaflets of Mimosa pudica is nutation.

Answer

False

Explanation

The closure of the leaflets of Mimosa pudica is a sleep movement. Sleep movements are rapid, reversible movements that are triggered by touch or other stimuli. Nutation is a slow, rhythmic movement that is caused by the changing position of the sun.

Question 5

TSH plays a major role in a feedback mechanism.

Answer

True

Explanation

TSH stands for thyroid-stimulating hormone. It is a hormone that is produced by the pituitary gland. It stimulates the thyroid gland to produce thyroid hormones, which are essential for metabolism. TSH plays a major role in the feedback mechanism that regulates the production of thyroid hormones.

Column Matching

Question 

Left Column	Right Column
A. Placenta formation	(i) Auxin
B. Exocrine gland	(ii) Progesterone
C. Coleoptile	(iii) Gastrin
D. Local hormone	(iv) Salivary gland

Answer

Left Column	Right Column
A. Placenta formation	(ii) Progesterone
B. Exocrine gland	(iv) Salivary gland
C. Coleoptile	(i) Auxin
D. Local hormone	(iii) Gastrin

Question 

Left Column	Right Column
A. Myotome muscle	(i) Pelvic fin
B. Flagellar movement	(ii) Anal fin
C. Paired fin	(iii) Fish
D. Unpaired fin	(iv) Euglena

Answer

Left Column	Right Column
A. Myotome muscle	(iii) Fish
B. Flagellar movement	(iv) Euglena
C. Paired fin	(i) Pelvic fin
D. Unpaired fin	(ii) Anal fin

Very Short Answer (VSA) Type Questions

Question 1

Give an example of seismonastic movement in plants.

Answer

Touch-me-not (Mimosa pudica)

Question 2

Name the secondary plant organs where transversely geotropic movement is found.

Answer

Roots

Question 3

Write the types of tropic movement.

Answer

Phototropism, geotropism, hydrotropism, thigmotropism, chemotropism.

Question 4

Flowers of Tulip shows what type of nastic movement?

Answer

Nyctinasty

Question 5

Which hormone helps to produce seedless fruits?

Answer

Gibberellins

Question 6

Give the full name of IAA.

Answer

Indole-3-acetic acid

Question 7

What is a synthetic hormone?

Answer

A hormone that is produced artificially.

Question 8

Which hormones help in apical dormancy in the plant?

Answer

Auxin

Question 9

What do you mean by natural auxin?

Answer

An auxin that is produced naturally by plants.

Question 10

Name the precursor of IAA synthesis.

Answer

Tryptophan

Question 11

From which gland GTH is secreted?

Answer

Anterior lobe of the pituitary gland.

Question 12

Give the full name of STH.

Answer

Somato Tropic Hormone.

Question 13

From which gland prolactin is secreted?

Answer

Anterior pituitary gland.

Question 14

Write the full form of ADH.

Answer

Antidiuretic hormone.

Question 15

Write one symptom of dwarfism.

Answer

Short arms and legs, with particularly short upper arms and upper legs.

Question 16

What is Schwann’s cell?

Answer

Schwann cell: A type of glial cell that surrounds and insulates axons in the peripheral nervous system.

Short Answer (SA) Type Questions

Question 1

What is nastic movement?

Answer

A plant’s non-directional response to a stimulus, such as light, touch, or temperature. For example, a Venus flytrap’s leaves snap shut when stimulated by an insect.

Question 2

What is geotropic movement?

Answer

A directional movement of a plant part in response to gravity is called geotropic movement.

• Example: Roots exhibit positive geotropism, meaning they grow downwards towards the ground. This helps them to anchor themselves in the soil and absorb water and nutrients.
• Example: Stems exhibit negative geotropism, meaning they grow upwards away from the ground. This helps them to reach for sunlight and carry out photosynthesis.

Question 3

What is a hydrotropic movement for example?

Answer

A directional movement of a plant part in response to water is called hydrotropic movement. For example, the roots of a plant will grow towards a source of water.

Question 4

Write two differences between tropic and nastic movement.

Answer

Differences between tropic and nastic movement:

• Tropic movements are directional, while nastic movements are not.
• Tropic movements are caused by a stimulus that is external to the plant, while nastic movements can be caused by internal or external stimuli.

Question 5

Give two examples of auxin which are used in agriculture.

Answer

Examples of auxin that are used in agriculture:

• Indole-3-acetic acid (IAA)
• 2,4-Dichlorophenoxyacetic acid (2,4-D)
• 4-chlorophenoxyacetic acid (4-CPA)

Question 6

Write two functions of cytokinin.

Answer

Functions of cytokinin:[

• Promote cell division
• Delay leaf senescence
• Stimulate the production of lateral buds

Question 7

What is parthenocarpy?

Answer

The development of fruit without fertilization is called parthenocarpy.

Question 8

Mention two differences between plant and animal hormones.

Answer

Differences between plant and animal hormones:

• Plant hormones are produced in the plant, while animal hormones are produced in the endocrine glands.
• Plant hormones are transported through the xylem and phloem, while animal hormones are transported through the blood.

Question 9

What is an endocrine gland? Give an example.

Answer

Endocrine gland: A gland that secretes hormones directly into the bloodstream.

• Example: Pituitary gland

Question 10

What is diabetes mellitus?

Answer

Diabetes mellitus:  A serious disease in which a person’s body cannot control the level of sugar in the blood.

Question 11

From where are thyroid-stimulating hormones and thyroxine secreted?

Answer

Thyroid-stimulating hormone (TSH): Pituitary gland

Thyroxine: Thyroid gland

Question 12

State the name and one function of the hormone secreted from ‘Islets of Langerhans’. 

Answer

Insulin: A hormone that is produced by the pancreas and that helps to regulate blood sugar levels.

Question 13

Write any one function of each of the cerebrum, cerebellum and medulla oblongata. 

Answer

Functions of cerebrum, cerebellum, and medulla oblongata:

• Cerebrum: Controls higher-order functions, such as thinking, planning, and language.
• Cerebellum: Controls balance, coordination, and movement.
• Medulla oblongata: Controls involuntary functions, such as breathing, heart rate, and digestion.

Question 14

What is a synapse? What is its function?

Answer

Synapse: The junction between two neurons where a nerve impulse is transmitted from one neuron to another.

Function: Synapses allow neurons to communicate with each other and transmit information throughout the nervous system.

Question 15

What is blind spot?

Answer

A blind spot is an area of the retina where there are no photoreceptor cells.

Question 16

What is a reflex arc?

Answer

A reflex arc is a neural pathway that mediates a reflex action. It is the basic functional unit of the nervous system that allows for rapid, involuntary responses to stimuli.

Long Answer (LA) Type Question

Question 1

What are the tropic, tactic and nastic movements? Describe with an example.

Answer

1. Tropic movements are directional movements of plant parts in response to external stimuli. They are caused by hormones called auxins. Examples of tropic movements are phototropism (movement towards light), geotropism (movement towards gravity), and hydrotropism (movement towards water).
2. Tactic movements are directional movements of motile cells or organisms in response to external stimuli. They are caused by taxis, which is a type of movement that is directed towards or away from a stimulus. Examples of tactic movements are phototaxis (movement towards light), chemotaxis (movement towards chemicals), and thigmotaxis (movement towards touch).
3. Nastic movements are non-directional movements of plant parts in response to external or internal stimuli. They are not caused by hormones. Examples of nastic movements are photonasty (movement of leaves in response to light), thigmonasty (movement in response to touch), and nyctinasty (movement in response to changes in light).

Question 2

Describe two types of tropic movements in plants.

Answer

Here are two types of tropic movements in plants:

Phototropism is the directional growth of a plant part in response to light. The shoots of plants grow towards the light, while the roots grow away from the light. This is because of a hormone called auxin, which is produced in the tips of the shoots. Auxin accumulates on the side of the shoot that is shaded, causing the cells on that side to grow faster. This causes the shoot to bend towards the light.

Geotropism is the directional growth of a plant part in response to gravity. The roots of plants grow downwards, while the shoots grow upwards. This is because of a hormone called auxin, which is produced in the tips of the shoots and roots. Auxin accumulates on the side of the roots that is facing down, causing the cells on that side to grow faster. This causes the roots to bend downwards.

Question 3

Discuss the types of nastic movements with examples.

Answer

1. Photonasty is a nastic movement that is caused by light. The most common example of photonasty is the closing of the leaves of the Mimosa pudica plant (also known as the touch-me-not plant).
2. Thigmonasty is a nastic movement that is caused by touch. The most common example of thigmonasty is the closing of the Venus flytrap plant’s leaves. When an insect lands on the leaves of this plant, the leaves close up quickly and trap the insect.
3. Chemotaxis is a nastic movement that is caused by chemicals. The most common example of chemotaxis is the opening of the Rafflesia flower.
4. Nyctinasty is a nastic movement that is caused by changes in light. The most common example of nyctinasty is the opening and closing of the sunflower flower. During the day, the sunflower flower opens up to face the sun. At night, the flower closes up.
5. Nastic movements are important for plants because they help them to respond to their environment. For example, photonasty helps plants track the sun, which ensures that they get enough sunlight for photosynthesis.

Question 4

Write three differences among tactic, tropic and nastic movement.

Answer

Here are three differences between tactic, tropic, and nastic movement:

Directionality:

• Tactic movements are directional, meaning that they always move towards or away from a stimulus.
• Tropic movements are also directional, but they always move in a specific direction, such as towards the light or towards the ground.
• Nastic movements are non-directional, meaning that they do not always move in a specific direction.

Stimulus:

• Tactic movements are caused by external stimuli, such as light, chemicals, or touch.
• Tropic movements are also caused by external stimuli, but they are specifically caused by gravity or light.
• Nastic movements can be caused by either internal or external stimuli.

Hormones:

• Tactic movements are not involved in hormones.
• Tropic movements are involved in hormones, specifically auxin.
• Nastic movements are not involved in hormones.

Question 5

Define hormone. State the characteristics of the hormone.

Answer

Hormone: Chemical messengers secreted by glands into the bloodstream to regulate various physiological processes.

Characteristics of Hormones:

1. Chemical nature: Usually proteins or steroids.
2. Mode of transport: Circulate through the bloodstream.
3. Target specificity: Act on specific target cells or organs.
4. Regulation: Controlled by feedback mechanisms.
5. Effects: Regulate growth, development, metabolism, and other bodily functions.

Question 6

Describe the sources and functions of auxin.

Answer

Sources of Auxin:

1. Apical meristems of shoot and root tips.
2. Young leaves.
3. Developing seeds and fruits.
4. Vascular tissues.

Functions of Auxin:

1. Stem elongation: Promotes cell elongation, resulting in the elongation of stems and shoots.
2. Apical dominance: Inhibits the growth of lateral buds, directing growth towards the apex.
3. Root development: Stimulates root growth and differentiation.
4. Phototropism: Influences the bending of plant parts towards a light source.
5. Gravitropism: Regulates the orientation of plant growth in response to gravity.
6. Fruit development: Promotes the development and ripening of fruits.

Question 7

State the sources and function of gibberellins and cytokinin. 

Answer

Sources of Gibberellins:

1. Apical meristems of shoot and root tips.
2. Young leaves.
3. Developing seeds and fruits.
4. Embryos.

Functions of Gibberellins:

1. Promotes cell elongation, resulting in the elongation of stems and shoots.
2. Stimulates seed germination by breaking dormancy and promoting the synthesis of hydrolytic enzymes.

Sources of Cytokinins:

1. Root tips.
2. Developing fruits and seeds.
3. Young leaves.
4. Apical meristems.

Functions of Cytokinins:

1. Promotes cell division and differentiation, especially in meristematic tissues.
2. Induces the formation and growth of new shoots from lateral buds.

Question 8

State the function of synthetic hormones.

Answer

The functions of synthetic hormones are:

1. Hormone replacement: Supplement or replace naturally occurring hormones.
2. Contraception: Prevent pregnancy.
3. Fertility treatments: Stimulate ovulation.
4. Manage hormone-related conditions: Treat menopause symptoms, endometriosis, etc.
5. Growth promotion: Stimulate growth in cases of deficiency or certain conditions.

Question 9

What are the endocrine glands of man and where are they located? What are the hormones secreted from them?

Answer

Question 10

Write the function of ADH. Where from it secreted?

Answer

Function of ADH (Antidiuretic Hormone):

1. ADH, also known as vasopressin, regulates water balance in the body by controlling the reabsorption of water in the kidneys.
2. Its main function is to decrease urine output and prevent excessive water loss from the body.
3. ADH acts on the collecting ducts of the kidneys, increasing their permeability to water and allowing more water to be reabsorbed back into the bloodstream.
4. By regulating water reabsorption, ADH helps maintain proper fluid balance, blood pressure, and electrolyte concentrations in the body.

Source of ADH secretion:

ADH is primarily secreted by the posterior pituitary gland, which is located at the base of the brain.

Question 11

Where from GTH and STH secreted? Mention any two functions of each STH and GTH.

Answer

GTH (Gonadotropin Hormones): Secreted from the anterior pituitary gland.

Functions of GTHs:

• Stimulates follicle development.
• Promotes sperm production.

STH (Somatotropin Hormone): Secreted from the anterior pituitary gland.

Functions of STH:

• Promotes overall body growth.
• Stimulates bone and muscle growth.

Question 12

Write the hormone’s name secreted from the pituitary. Write one of the functions of each hormone.

Answer

Hormones secreted from the pituitary gland:

1. Function of  Growth Hormone (GH): Promotes growth and development of bones and tissues.
2. Function of  Prolactin (PRL): Stimulates milk production and breastfeeding.
3. Function of  Adrenocorticotropic Hormone (ACTH): Stimulates the production and release of cortisol from the adrenal glands.
4. Function of  Thyroid-Stimulating Hormone (TSH): Stimulates the thyroid gland to produce and release thyroid hormones.
5. Function of   Follicle-Stimulating Hormone (FSH): Stimulates follicle development in females and sperm production in males.
6. Function of   Luteinizing Hormone (LH): Triggers ovulation in females and stimulates testosterone production in males.
7. Function of  Antidiuretic Hormone (ADH): Regulates water balance by controlling water reabsorption in the kidneys.

Question 13

Draw a diagram of the vertical section of the human eye and label any six points.

Answer

Question 14

What is a neurone? Describe the structure of the neurone with a diagram.

Answer

A neuron is the basic unit of the nervous system. It is a specialized cell that receives, processes and transmits information. Neurons are made up of three main parts: the dendrites, the cell body, and the axon.

Here are some additional details about the structure of a neuron:

• Dendrites: Dendrites are typically short and branched, and they receive signals from other neurons.
• Cell body: The cell body contains the nucleus and other organelles of the neuron. It is also where protein synthesis takes place.
• Axon: The axon is a long, thin extension of the cell body that transmits signals to other neurons.
• Myelin sheath: The myelin sheath is a fatty layer that surrounds the axon and insulates it. This helps to speed up the transmission of signals.
• Nodes of Ranvier: Nodes of Ranvier are gaps in the myelin sheath. These gaps allow the electrical signals to jump from node to node, which further speeds up the transmission of signals.

Question 15

What is reflex action? Explain it with an example.

Answer

A reflex action is an involuntary response to a stimulus. It is a quick, automatic response that does not require conscious thought. An example of a reflex action is the knee-jerk reflex. When the doctor taps your knee with a rubber hammer, your leg kicks out involuntarily. This is because the tap on your knee sends a signal to your spinal cord, which then sends a signal to your leg muscles to contract.

Reflex actions are important for our survival. They allow us to react quickly to danger or to other unexpected stimuli. For example, if you touch a hot stove, you will automatically pull your hand away. This reflex action helps to protect you from being burned.

Question 16

What is locomotion? Mention the role of the cerebellum and inner ear in human locomotion.

Answer

Locomotion is a directional movement that enables someone or something to move from one location to another.

Here are some of the specific roles of the cerebellum and inner ear in human locomotion:

• Cerebellum: The cerebellum helps to coordinate the movements of the limbs and maintain balance. It does this by receiving input from the muscles, joints, and vestibular system (inner ear). The cerebellum then sends signals to the muscles to help them move smoothly and accurately.
• Inner ear: The inner ear helps to sense the body’s position in space and provides information about movement. It does this by containing three semicircular canals and two otolith organs. The semicircular canals sense angular acceleration, while the otolith organs sense linear acceleration and gravity. The information from the inner ear is sent to the brain, which then uses it to coordinate movement and maintain balance.