These solutions have been prepared by experienced teachers.
.png "RBSE Solutions for Class10 Science Chapter 6 Control and Coordination")
If you are preparing for RBSE class 10 board exams, then these solutions of intext and end exercise questions will help you a lot. These solutions cover a complete syllabus and will let you solve homework and assignments in an easy way. You can also go through MCQs of Control and Coordination.
|
Board |
RBSE |
|
Subject |
Science |
|
Chapter |
Control and Coordination |
|
No. of Intext questions |
14 |
|
No. of End exercise questions |
12 |
|
Prescribed Book |
NCERT Science |
Control and Coordination
Answers of Questions on Page 105
Q.1 What is the difference between a reflex action and walking?
Answer
Difference between Reflex action and walking
|
Reflex Action |
Walking |
|
A reflex action is an automatic and rapid response to a stimulus. |
Walking is a voluntary action. |
|
Spinal cord is involved in it. |
It is a conscious and deliberate action i.e. it is done after a thought is processed |
|
No thinking or feeling involve incontrolling the action. |
we have acquired through learning |
|
Spinal cord is involved in this. |
It is directly controlled by hind-brain |
|
Our eyes close when bright light falls on it, |
Walking in a straight line, riding a bicycle, |
Q.2 What happens at the synapse between the neurons?
Answer
Synapse is a very small gap between the last portion of axon of one neuron and the dendron of the other neuron. At the synapse the two neurons join together. It acts as A one way valve to transmit impulses.
Synapse performs the following tasks:
1. It allows the information to pass from one neuron to another.
2. It ensures the passage of nerve impulse in one direction only.
Q.3Which part of the brain maintains posture equilibrium of the body?
Answer
Cerebellum (a part of hind brain) maintains the posture and equilibrium of the body.
Q.4 How do we detect the smell of an agarbatti (incense sticks)?
Answer
Olfactoreceptors (in nose) send the information about the smell of incense stick to fore-brain where olfactory lobes of fore brain analyse and produce the sensation of smell. The for-brain interprets it along with information received from other receptors as well as with information that is already stored in the brain.
Q.5 What is the role of the brain in reflex action?
Answer
Reflex action is completed by spinal cord. There is no role of brain in reflex action. These involuntary actions are controlled by the spinal cord which takes place immediately without thinking. However impulse or input also goes to the brain.
Answers of Questions on Page 108
Q.1 What are plant hormones?
Answer
Plant hormones are also called phytohormones. They are the chemical substances which help in controlling growth, flowering, height, development of plants and
their response to the environment.
Following are the main phytohormones –
i). auxins,
ii). Gibberllins
iii). Cytokinins
iv). abscisic acid
v).ethylene.
Q.2 How is the movement of leaves of the sensitive plants different from the movement of a shoot towards light?
Answer
|
Movement of leaves in sensitive plant |
Movement of shoot |
|
1 Movement of leaves of sensitive plant is independent of growth |
1. movement of a shoot towards light depends on |
|
2 Touch is the stimulus. |
2Light is the stimulus. |
|
3 This movement is caused by sudden loss of water. |
3 This movement is caused by an unequal growth. |
Q.3 Give an example of a plant hormone that promotes growth.
Answer
Plant hormone auxin and gibberellins promote growth of plant.
Q.4 How do auxin promote the growth of a tendril around a support?
Answer
Auxin plant hormone is found at the tip tendril When the tip of a tendril touches a support, then the auxins present in its tip move to that side of tip which is away from the support and So, due to more auxins in it, the side of tendril away from the support grows faster than the side which is in contact with the support that’s why the tendril bend around the support.
Q.5 Design an experiment to demonstrate hydrotropism.
Answer
The movement of plant parts towards the availability of water is called hydrotropism. Roots always move toward water. we plant tiny seedling in two different trough
A and B. Near them we place a clay pot filled with water. We water the soil in trough A daily but Do not water the soil in trough B. Leave both the troughs for a few days.
After a few days we dig up the seedlings carefully from both the troughs without damaging their roots. We find that the root of seedling in trough A is straight. On the other hand, the root of seedling in trough B got bent towards the clay pot containing water.
This experiment shows that the root of a plant grows towards water.
Answers of Questions on Page 111
Q.1 How does chemical coordinated take place in animals?
Answer
Chemical coordinated takes place in animals by secretinghormones from endocrine glands.
Q.2 Why is the use of iodised salt advisable?
Answer
Iodine is essential for the synthesis of thyroxin. Deficiency of iodine in the body causes swollen neck or through which called goiter.
Q.3 How does our body response when adrenalin is secreted into the blood?
Answer
Adrenalin hormone is secreted by endocrine gland ‘Adrenal’, located on each kidney. When adrenalin hormone is secreted into blood, heart beat become faster to supply more oxygen to muscles, but at the same time blood supply is reduced to digestive system and skin, so breathing rate increases. This leads the animal (human) body to deal with the adverse condition.
Q.4 Why are some patients of diabetes treated by giving injections of insulin?
Answer
Diabetes is caused by deficiency of Insulin hormone. Insulin regulated sugar
metabolism. When amount of insulin decreases in blood, it leads to high sugar
level in blood that’s why, patient of diabetes are treated by giving injections
of insulin.
Answers of End Exercise Questions
Q.1 Which of the following is a plant hormone?
(a) Insulin
(b) thyroxin
(c) Oestrogen
(d) cytokinin
Answer. (d) cytokinin
Q.2 The gap between two neurons is called a
(a) Dendrite
(b) synapse
(c) Axon
(d) impulse
Answer (b) synapse
Q.3 The brain is responsible for
(a) Thinking
(b) regulating the heart beat
(c) Balancing the body
(d) all of the above
Answer (d) all of the above
Q.4 What is the function of receptors in our body? Think of situations where receptors don’t work properly. What problems are likely to arise?
Answer
Receptors – These are the nerve cells which receive information from surrounding environment, are called receptors.
|
Stimulus/information |
Receptors |
|
Smell |
Olfactoreceptors |
|
Taste |
Tangoreceptors |
|
Light |
Photo receptors |
|
Pain |
Algesireceptors |
|
Sound |
Phono receptors |
When any receptor does not work properly, we will not be able to respond any stimulus or changes in our surrounding.
For example – In cold, our nose does not work properly, we are not able to detect any smell and taste of food properly because our olfactory receptors do not work
properly at this time.
Q.5 Draw the structure of neuron and explain its function?
Answer
Structure of Neuron
.webp "Structure of Neuron")
Function of a neuron :-
The information passing through neurons is in the form of chemical and electrical signals are called nerve impulse. Dentrite receive information of change
(stimuli) in surrounding and sensory neuron transmit this information to the
central nervous system. This information travels in form of an electrical impulse. This impulse travels from dentrite to the cell body and then along the axon to its end.
At the end the electrical impulse changes into chemicals which reach the dentrites of other nerve cell where they create electrical impulse. The gap between two nerve cells is called synapse. In this way impulse travel in body.
Q.6 How does phototropism occur in plants?
Answer
We take a conical flask filled half with water and cover the neck of the flask a wire mesh. Now we keep two – three germinated been seeds on the wire mesh in such a way that water is in contact of germinated seeds.
Now we keep the flask in a cardboard in such a manner that the open side of the box faces light from window. After two or three days we see that shoot turns towards the light and roots moves away from the light.
Now we turn the flask away from the sun and roots towards the sun and keep it for four to five days.After that we see the flask the shoot turns again towards the
light and roots moves again away from light. This shows the phototropism.
Q.7 Which signals will get disrupted in case of spinal cord injury?
Answer
Spinal cord carries messages to brain and from brain to effector organs. In case of spinal cord injury the signals for reflex action and motor nerves connected to the
receptor and this part will get disrupted.
Q.8 How does chemical coordination occur in plants?
Answer
Plants do not have any nervous system so all the coordination are conducted by chemicals. These chemicals are called plant hormone. Plants respond to light, water, gravity and other chemicals. Auxins, gebberellins, cytokinins and abscisic acid etc
Q.9 What is the need for a system of control and co-ordination in an organism?
Answer
Our body performs different kinds of activities and during these activities different organs work in coordination. For example, when we take food, our eyes locate the food, our nose detects the smell, our hand brings the food to our mouth, the teeth and jaw muscles chew the food and saliva starts the digestive process.
Q.10How are involuntary actions and reflex actions different from each other?
Answer
Involuntary actions: – The actions which are performed without the will of organism but controlled by the brain are called involuntary actions such as salivation, heart function, blood pressure breathing etc.
Reflex action: – The action which is spontaneous and automatic without the response of brain and the will of organism such removing of hand when a pin is pierced to it.
Q.11Compare and contrast nervous and hormonal mechanisms for control and coordination in animals.
Answer
Comparison and contrast between nervous and hormonal mechanism
|
Nervous mechanism |
Hormonal mechanism |
|
(i)This is performed by nervous system. (ii) Information (impulses) is received by (iii) Chemical change occurs in the cellular composition of muscular cells. (iv) It is related to control and coordinate the functions. |
This is a performed by chemical substances called hormones. These hormones are secreted by endocrine glands.
Hormones produced in on part of the organism, move to other part of body. It is also related to control and coordination. |
Q.12 What is the difference between the manner in which movement in the sensitive plant and movement in our legs takes place?
Answer
When a part sensitive plant is touched. The information that the plant has been touched is communicated from cell to cell using electrical and chemical means, but plants have no specialized tissue for the conduction of information. Finally the cells should change their shape. It is performed by change in amount of water.
In animals, movement of legs is controlled by nervous system. Movement in legs is a voluntary action. When we think to move our legs, the brain takes action
based on thinking. Forebrain is associated where the sensory information is interpreted by putting it together with information from other receptors as
well as the information already stored in the brain. On this basis decision is taken and information already stored in the brain. On this basis decision is
taken and information is passed to motor area which controls the movement of voluntary muscles.
|
Movement in a sensitive plant |
Movement in legs of a human |
|
1. The leaves of a sensitive plant like are sensitive to touch. Eg. |
1. Our leg is in control of nerve muscles. |
|
2. This is not controlled by any part of the plant. |
2. This is controlled by brain and spinal cord. |
|
3. In this, cells change their shape on changing the amount of water |
3. Amount of water has no effect on the movement of muscles. |
RBSE Class 10 Science Questions Answers
|
Chapter |
Chapter Name |
|
1 |
|
|
2 |
|
|
3 |
|
|
4 |
|
|
5 |
|
|
6 |
|
|
7 |
|
|
8 |
|
|
9 |
|
|
10 |
|
|
11 |
|
|
12 |
|
|
13 |
Related Topics