- 1 Class 10 Science Chapter 7 Important Questions with Answers Control and Coordination
- 1.1 Control and Coordination Class 10 Important Questions Very Short Answer Type
- 1.2 Control and Coordination Class 10 Important Questions Short Answer Type I
- 1.3 Control and Coordination Class 10 Important Questions Short Answer Type II
- 1.4 Control and Coordination Class 10 Important Questions Long Answer Type
Solved the very best collection of Control and Coordination Class 10 Science Important Questions and Answers Chapter 7 Pdf from the latest NCERT edition books, It will help you in scoring more marks in CBSE Exams.
Class 10 Science Chapter 7 Important Questions with Answers Control and Coordination
Class 10 Chemistry Chapter 7 Important Questions with Answers Control and Coordination
Control and Coordination Class 10 Important Questions Very Short Answer Type
Name the sensory receptors found in the nose and on the tongue. (2012)
- Nose has olfactory receptors which detect smell.
- Tongue has gustatory receptors which detect taste.
How do the shoot and roots of a plant respond to the pull of earth’s gravity? (2012)
- Shoot of a plant always grows away from the pull of gravity or shows negative geotropism.
- Root of the plant always grows towards the pull of gravity or shows positive geotropism.
Name two tissues which provide control and coordination in animals. (2013)
Nervous tissue and muscular tissue provide control and coordination in animals.
Name two parts which constitute the central nervous system. (2013)
The central nervous system (CNS) consists of the brain and the spinal cord.
Name the two components of peripheral nervous system. (2014)
Two components of peripheral nervous system:
- Autonomic nervous system.
- Voluntary nervous system.
Name one plant hormone which inhibits growth. Write its one more function. (2015)
Abscisic acid is a plant hormone which functions mainly as a growth inhibitor.
- It promotes the dormancy in seeds and buds.
- It promotes the wilting and falling of leaves.
Control and Coordination Class 10 Important Questions Short Answer Type I
Name the gland and the hormone secreted by the gland, which are associated with the following problems:
(i) a girl has grown extremely tall.
(ii) a woman has a swollen neck. (2014)
(i) Pituitary gland → human growth hormone
(ii) Thyroid gland → thyroxine hormone
Name the plant hormones responsible for the following functions: (2015)
(i) growth of the stem
(ii) promotes cell division
(iii) wilting of leaves
(iv) inhibits growth
|(i) growth of the stem||Auxin/ gibberellin|
|(ii) promotes cell division||Cytokinin|
|(iii) wilting of leaves||Abscisic acid|
|(iv) inhibits growth||Abscisic acid|
Control and Coordination Class 10 Important Questions Short Answer Type II
(a) Name the part of brain which controls (2012)
(i) voluntary action,
(ii) involuntary action.
(b) What is the significance of the peripheral nervous system? Name the components of this nervous system and distinguish between the origin of the two.
(a) (i) All the voluntary actions of the body are coordinated by the cerebellum.
(ii) Various involuntary actions are controlled by Medulla.
(b) Peripheral nervous system is extended between central nervous system and body parts. The communication between the central nervous system and the other parts of the body is facilitated by the peripheral nervous system. On the basis of their origin, it is divided into two types of nerves.
(i) Cranial nerves. These nerves extend between the brain and parts of head except 10th cranial nerves which extends up to the abdomen.
(ii) Spinal nerves. There nerves extend between spinal cord and the body parts.
|Character||Cranial nerves||Spinal nerves|
|1. Extension||Between brain and body parts.||Between spinal cord and body parts.|
|2. Number||12 pairs||31 pairs|
|3. Nature||May be sensory or motor or mixed.||Always mixed.|
Describe an activity to illustrate the phenomenon of phototropism and explain why does this occur. (2012)
Experiment. We take a potted plant growing in a transparent glass jar. When this potted plant is kept in the open space, the stem of the plant grows straight up towards the Sun while root of the plant grows straight but in the downward direction.
Now keep this plant near the window in a dark room in such a way that sunlight falls on it from the right side only. After some days, we observe that the stem of the plant bends towards the right side towards the light whereas the root bends to the left side away from the light.
This experimental setup demonstrates phototropism, i.e., the shoot of the plant bends towards light This occurs because the plant stem responds to light and bends towards it due to the action of auxin hormone.
(i) When sunlight comes from above, the auxin hormone present in the tip of the stem spreads uniformly down the stem. So the stem grows straight up.
(ii) When the sunlight falls on one side, the auxin hormone prefers to stay in shade as shown in the diagram.
(iii) Due to uneven distribution of auxin hormone, the side with more auxin will grow faster than the other side. Thus, the stem bends towards the side in the direction of light.
(a) Name the hormone which is secreted when growing plants detect light. Mention its site of secretion in a plant.
(b) Explain why do plants appear to bend towards light? (2012)
(a) Auxin hormone is secreted in the growing plant which detects light.
It is present in the tip of the growing stem.
(b) Plants appear to bend towards light. As more auxin is produced on the shaded side than on the lighted side of the stem, so stem grows faster on the shaded side than on the lighted side.
Name the diseases by which a person is likely to suffer due to the deficiency of:
(i) Iodine; (ii) Insulin
(b) How the timing of secretion and amount of hormone secretion are regulated in human system. Explain with example.
(a) Diseases due to the deficiency of
(i) Iodine – Goitre
(ii) Insulin – Diabetes.
(b) The timing and amount of hormones released by various glands are controlled by the ‘feed back mechanism’ which is in-built in the body.
For example, if the sugar level in the blood rises too much, they are detected by the cells of pancreas which respond by producing and secreting more insulin into blood. And as the blood sugar falls to a certain level, the secretion of insulin is reduced automatically.
Define the following: (2013)
(a) Reflex action
(a) Reflex action. A reflex action is defined as a spontaneous, automatic and mechanical response to a stimuli without the will of an animal. In such actions there is no involvement of the brain. All reflex actions are conveyed through the spinal cord by a path called reflex arc.
(b) Synapse. A microscopic gap between a pair of adjacent neurons over which nerve impulses pass when going from one neuron to the next is called a synapse.
(c) Phototropism. It is the response of the plant parts to the external stimulus of light. The stem shows positive phototropism as the stem of the plant grows in the direction of light while root shows negative phototropism as the root of the plant grows away from the light. This growth is controlled by the auxin hormone.
Mention three characteristic features of hormonal secretions in human beings. (2014)
- A group of endocrine glands which produces various hormones is called an endocrine system. The endocrine system is also called hormonal system.
- The endocrine system also helps in coordinating the activities of our body. The endocrine system in our body consists of a number of glands (or tissues) which make, store, and release chemicals called hormones.
- The working of endocrine glands is controlled by our nervous system. The hormones produced by endocrine glands act as messengers between the nervous system and the organs of our body.
Explain how the movement of leaves of a sensitive plant is different from movement of shoots towards light? (2014)
The movement of plant shoot towards light is called phototropism. It is a directional movement in which there is growth movement of a plant part (shoot) in response to an external stimulus (light). The plant stem responds to light and bends towards it due to the action of ‘auxin hormone’.
The movement of the leaves of a sensitive plant is called Nastic movement. It is also called Thigmonasty. It is a non-directional movement of plant part (leaves) in response to touch or vibration. The folding up of leaves of a sensitive plant (like mimosa) on touching is due to the sudden loss of water from pad like swellings called pulvini present at the base of all leaves.
Name the system which facilitates communication between central nervous system and the other parts of the body. Mention two types of nerves it consists of along with their organs of origin. (2015)
Peripheral nervous system facilitates communication between central nervous system and the other parts of the body.
Two types of nerves:
- Cranial nerves arise from the brain and spread throughout the head.
- Spinal nerves arise from the spinal cord along most of the length of the spinal cord and spread throughout the body except the head.
State the function of receptors in our body. Think of any three situations where receptors in the body do not work properly. Mention the problems which are likely to arise. (2015)
Receptors are present in all parts of our body, for example, in the skin, eyes, nose, tongue, etc.
A receptor is a cell (or a group of cells) in a sense organ which is sensitive to a particular type of stimulus such as light, sound, smell, taste, heat, pressure, etc. The different sense organs contain receptors for detecting different stimuli.
- The eyes have light receptors called photoreceptors (which can detect light).
- Ears have sound receptors called phonoreceptors (which can detect the sounds).
- The nose has smell receptors called olfactory receptors which can detect the smell.
- Tongue has taste receptors which are called gustatory receptors which detect taste.
- Skin has receptors called thermoreceptors which detect touch, pressure, hotness, coldness.
When receptors do not work properly, the environmental stimuli are not able to create nerve impluses and the body does not respond.
When receptors are damaged, the external stimuli transferring signals to the brain are not felt.
- During fever, taste buds do not work properly and as a result, taste of the food eaten is not felt properly thus enzyme secretion is also affected.
- When a person is suffering from a cold, the nostrils are filled with mucus. Then smell of the surrounding is not felt properly. This is due to interruption in reacting to the sense of smell by the olfactory receptor.
- When skin receptors are damaged, and we accidentally touch a hot object, then our hands might get burnt as the damaged receptor cannot perceive the external stimuli of heat and pain.
Compare and contrast nervous and hormonal mechanisms for control and coordination in the animals. (2017 D)
- Nervous mechanism involves the movement of stimulus and response information in the form of chemical and electrical impulses through specialised neuron cells.
- Nerve impulses are fast in their actions.
- Response is immediate in nervous control.
- Hormones are special chemicals produced by specialised organs. Information reaches the target organs through the blood stream.
- Hormones are slow in their actions.
- Response is usually slow.
What is reflex arc? Draw a labelled diagram to show reflex arc on touching a very hot object. (2017 OD)
Reflex Arc. The path followed during a reflex action is called reflex arc.
Control and Coordination Class 10 Important Questions Long Answer Type
(a) Write three main functions of the nervous system.
(b) In the absence of muscle cells, how do plant cells show movement? (2014)
(a) Main functions of the nervous system:
- Coordinate the activities of the body.
- Helps all other systems of the body to work together.
- The nervous system receives information from the surroundings, processes it, interprets it and then responds accordingly.
(b) The movement in any part of a plant is usually a growth movement or change in shape of body parts.
- The movements of the plant part are usually caused by an unequal growth in its two regions by the action of plant hormones, under the influence of the stimuli like light, force of gravity, chemical substances, water, touch etc.
- The change in shape occurs by changing the amount of water in the body part. Water causes swelling and shrinking which causes movement.
Explain feed back mechanism for regulation of hormonal secretion with the help of one example.
State two different types of movement in plants. Mention two points of difference between them. (2014)
(a) The timing and amount of hormones released by various glands are controlled by the ‘feedback mechanism’ which is in-built in our body.
Example, if the sugar level in the blood rises too much, it is detected by the cells of pancreas which responds by producing anci secreting more insulin into the blood; and as the blood sugar falls to a certain level, the secretion of insulin is reduced automatically.
(b) The plant movements made in response to external stimuli fall into two main categories (i) tropism and (ii) nasties.
(i) Tropisms: A growth movement of a plant part in response to an external stimuli in which the direction of stimulus determines the direction of response is called tropism. So it is a directional movement.
(ii) Nasties: The movement of a plant part in response to an external stimulus in which the direction of response is not determined by the direction of stimulus is called nastic movement.
- The direction of stimulus determines the direction of movement of the plant part.
- All the tropisms are growth movements.
- The direction of movement is not determined by the direction of stimulus.
- Nasties are growth independent movements.
(a) Define reftex action. State its significance.
(b) How do plants respond to external stimuli? (2015)
(a) A reflex action is an automatic response to a stimulus. The simplest form of response in the nervous system is reflex action. This is a rapid, automatic response to a stimulus which is not under the voluntary control of the brain. It is described as an involuntary action. The pathway taken by nerve impulses in a reflex action is called the reflex arc.
Reflex actions are the actions which we perform without thinking to protect ourselves. For example, coughing is a reflex action which clears our windpipe. The pupils of our eyes get smaller in bright light. This reflex action protects the retina of our eyes from damage due to much light. The pupils of our eyes get bigger in dim light so as to help us see properly even in dim light.
(b) Plants respond to external stimuli such as light, touch, etc. A growth movement of a plant part in response to an external stimulus in which the direction of stimuli determines the direction of response in called tropism.
- If the growth of a plant part is towards the stimuli, it is called positive tropism.
- If the growth of a plant part is away from the stimulus, then it is called negative tropism.
Types of tropism:
- The movement of a plant part in response to light is called phototropism.
- The movement of a plant part in response to gravity is called geotropism.
- The movement of a plant part in response to chemicals is called chemotropism.
- The movement of a plant part in response to water is called hydrotropism.
- The directional growth movement of a plant part in response to the touch of an object is called thigmotropism.
Nasties (or Nastic Movements). The movement of a plant part in response to an external stimulus in which the direction of response is not determined by the direction of stimulus is called nastic movement.
- The folding up of a the leaves of a sensitive plant on touching is an example of nastic movement. Here the stimulus is touch.
- The opening up of the petals of dandelion flowers in morning in bright light and closing in the evening when the light fades is an example of nastic movement. In this case the stimulus is light.
Draw the structure of Neuron and explain its function.
How does Phototropism occur in Plants? (2017 OD)
Nerve cell or neuron is a functional unit of the nervous system.
Function. The information acquired at the end of the dendritic tip of a neuron sets off a chemical reaction which creates an electrical impulse. This impulse travels from the dendrite to the cell body along the axon at its end. At the end of axon, the electrical impulse sets off the release of some chemicals, which cross the synapse and start a similar electrical impulse in a dendrite of the next neuron.
In this way nerve impulses travel in the body, from one neuron to another till it reaches the brain or the target organ. Thus, a nervous tissue is made up of an organised network of nerve cells or neurons which are specialised in conducting information via electrical impulses from one part of the body to another.
(b) Phototropism is the response of the plant parts to the external stimulus of light. The stem of the plant grows in the direction of light while root grows away from the direction of light. This growth is controlled by the auxin hormone of the plant. The concentration of auxin stimulates the cells to grow longer on the side of the shoot (stem and branches) which is away from the light. Thus, the plant appears to bend towards light.