NCERT Solutions for Class 10 Science Chapter 7
NCERT Solutions for Class 10 Science Chapter 7 Control and Coordination intext questions answers on Page 119 or Page 122 or Page 125 and Exercises answers in English as well as Hindi Medium free to download in PDF file format.All the Offline Apps and NCERT Solutions are based on latest CBSE Syllabus 2020-21. 10th Science Biology solutions of questions given on पेज 132 or पेज 136 or पेज 138 or अभ्यास के प्रश्न उत्तर in हिंदी मीडियम are free to view online or download in PDF format. Download Offline Apps 2020-21 to use it without internet.
NCERT Solutions for Class 10 Science Chapter 7
|Subject:||Science – Biology|
|Chapter 7:||Control and Coordination|
10th Science Chapter 7 Answers in English & Hindi Medium
All Subjects NCERT Solutions for class 10 are in PDF and Free to download. NCERT Solutions for Class 10 Science Chapter 7 Control and Coordination Intext questions and chapter end exercises question answers are given below to free download. All the answers are updated for session 2020-21 based on latest NCERT Books 2020-21 following the current CBSE Syllabus 2020-2021.
10th Science Chapter 7 Answers in English Medium
10th Science Chapter 7 Answers in Hindi Medium
10th Science Chapter 7 Answers in PDF Form
Difference between Voluntary and Involuntary Actions
The actions are under the will or consciousness of the individual. They may or may not involve information from receptors or sense organs. Impulses originate in the brain. Every voluntary action occurs under conscious directions from brain. The actions employ voluntary muscles. Voluntary actions do not occur in the form of an arc. Mainly three parts are involved brain, efferent neuron and effector organ.
Actions occur without consulting the will. Involuntary actions always occur in response to stimuli picked up by receptors. Impulses originate in the region of receptors. Brain is seldom consulted consciously through an involuntary action always involves spinal cord or brain for transfer of information from afferent neurons to efferent neurons. The actions employ involuntary muscles but occasionally voluntary muscles also get involved.
How does over production of hormones controlled? Give one example.
Endocrine glands or ductless glands produce hormones and directly pour their secretion in the blood. These glands do not go on producing hormones. Their secretion is controlled by feedback information system. Thus their over production of hormones is controlled.
For example, a hormone called TSH is secreted by pituitary gland. TSH stimulates the production of thyroxine from the thyroid gland. But if there is over production of thyroxine hormone, this hormone acts on pituitary gland and controls the production of TSH. As a result, the production of thyroxine by the thyroid gland is controlled. Thus, TSH and thyroxine control the level of each other. This mechanism of opposing effect is called feedback mechanism.
Differentiate between sensory neurons and motor neurons.
Sensory neurons carry sensory impulse from receptors to the nerve cell body or to the region which receives sensory impulses. Whereas motor neurons carry information of action to be carried by the conserved voluntary muscles.
How is brain protected in our body?
Human brain is lodged in a bony case, the cranium which protects it from injuries. It is wrapped in three sheets of connective tissue, known as meninges. The space between the meninges is filled with cerebrospinal fluid which helps in absorption of shocks.
Name the part of the brain responsible for precision of voluntary action and maintaining body posture and balance of the body.
Fore-brain is responsible for precision of voluntary action.
Cerebellum is responsible for maintaining the posture and keeping balance of the body.
What is the role of the brain in reflex action?
Reflex actions are controlled by spinal cord, although the information input also goes on to reach the brain. However, conditioned reflexes (based on previous experiences), such as salivation after seeing good food are controlled by cerebral cortex of brain.
How does adrenaline help an athlete to prepare for running?
Adrenaline causes the heart beat faster, resulting in supply of more oxygen. It causes reduction in supply of blood to the digestive system and skin. This diverts the blood to our skeletal muscle. The breathing rate also increases. All these responses together help an athlete to prepare for running.
What is meant by Tropic movement? Why do tropic movements takes place in plants?
The directional (tropic) response of plants shown by the plants towards or away of the stimulus such as light, water, gravity, etc. is known as tropism.
Tropic movements in plants are growth related. Plants respond to stimuli slowly by growing in a particular direction, either towards stimulus or away from. This growth causing tropic movement is regulated by the plant hormone called auxin.
Questions for Practice
State the function of any three of the structural and functional unit of nervous system.
Nervous system: Main parts of nervous system are: (i) Central nervous system, (ii) Peripheral nervous system, (iii) Autonomous System.
(i) Central Nervous System: It consist of
(a) Brain receives information carrying impulses from all the sensory organs (by sensory nerves) of the body and also from the spinal cord. The brain respond to the information by sending its own instructions (through motor nerves) to the muscles and glands to act accordingly. The brain also stores information and act as organ of thought and intelligence.
(b) Spinal cord: It is concerned with spinal reflex actions and the conduction of nerve impulses to and from the brain.
(ii) Peripheral Nervous system: it is composed of cranial nerves (nerves from the brain) and the spinal nerves. Both of these consist of sensory and motor neurons. So, they carry sensations to and messages from the brain and the spinal cord.
(iii) Autonomous Nervous System: It is that part of the peripheral nervous system which controls the activities of the internal organs such as stomach, heart-beat, etc. automatically even without our thinking about them. Its nerves are attached to the smooth muscles and control the activities of internal organs of the body involuntarily, many these nerves are connected with the mid- brain and hind-brain.
Questions from Board Papers
(a) If the cerebellum is not functioning properly, state the activities of our body that are affected.
(b) how do muscles move?
(a) Cerebellum is not functioning properly may affect-
(i)Walking in straight line
(ii)Riding a cycle
(iii)Maintaining the posture and balance of the body
(iv)Movement is very coordinate, the patient sways in walking and tend to fall towards the affected side.
(v)It is responsible for precision of voluntary actions.
(b) When the decision to move is conveyed by a nerve to a muscle, it has to act. In response to nervous electrical impulses. The special proteins of the muscle change both their shape and their arrangement in the cell. This new arrangement of these proteins give the muscle cells a shorter form that causes movement of the muscle.
“Use of iodised salt is essential”. List three reasons to justify this statement.
(i) Iodised salt supplies sufficient amount of iodine through our diet, even in the areas where iodine is not available naturally through water or otherwise in diet.
(ii) Iodine is necessary for the thyroid glands to make thyroxine hormone.
(iii) Proper supply of iodine maintains thyroxine level that regulates carbohydrate, protein, and fat metabolism to provide the best balance for growth.
(iv) Deficiency of iodine causes many diseases such as Goitre.
Important Questions on 10th Science Chapter 7
They sense the external stimuli such as heat or pain.
They also trigger an impulse in the sensory neuron which sends message to the spinal cord. When the receptors are damaged, the external stimuli transferring signals to the brain are not felt. For example, in the case of damaged receptors, if we accidentally touch any hot object, then our hands might get burnt as damaged receptors cannot perceive the external stimuli of heat and pain.
Walking, on the other hand, is a voluntary action. It is under our conscious control.
Reflex arcs are formed in the spinal cord and the information (input) reaches the brain. The brain is only aware of the signal and the response that has taken place. However, the brain has no role to play in the creation of the response.
Gibberellins help in the growth of the stem.
Auxins help in the growth of the stem.
Cytokinins promote cell division.
Abscisic acid is one example of a hormone which inhibits growth.
When secreted in large amounts, it speeds up the heartbeat and hence supplies more oxygen to the muscles. The breathing rate also increases due to contractions of diaphragm and rib muscles. It also increases the blood pressure. All these responses enable the body to deal with any stress or emergency.