CBSE TEST PAPER-01 SCIENCE and TECHNOLOGY (Class-10) Chapter 7 : Control and Coordination Ch. 7 - Control and Coordination class 10 Trend setter solved CBSE Test paper-03 VERY VERY SHORT ANSWER QUESTIONS (1 Mark) 1. Mention one example of chemotropism. [2010 (T-I)] Ans: Growth of pollen tube towards the ovule 2. Mention the function of hind brain in humans. [2010 (T-I)] Ans: Main function of hind brain in humans is to maintain the posture and balance of the body. It is responsible for the precision of voluntary actions like walking in straight line, riding a bicycle. 3. Name and explain the function of the hormone secreted by the pituitary gland in humans.[2010 (T-I)] Ans: Growth hormone is secreted by the pituitary gland. This hormone regulates growth and development of the body. If there is a deficiency of this hormone in childhood, it leads to dwarfism and excess of this hormone leads to giant body size 4. State the main function of abscisic acid in plants.[2010 (T-I)] Ans: Abscieic acid is the plant hormones which stop plant growth Abscieic acid also perform following functions in plants: · It promotes seed dormancy by inhibiting cell growth. · It is involved in the opening and closing of stomata. · It is also responsible for the shedding of leaves. 5. Name the hormone the secretion of which is responsible for dramatic change in appearance in girls when they approach 10-12 years of age. [2008] Ans: Oestrogen from ovaries 5. Name the hormone that helps in regulating level of sugar in our blood. Name the gland that secrets it. Ans: Hormone : Insulin Gland : Pancreas VERY SHORT ANSWER QUESTIONS (2 Mark) 6. What are the end products formed during fermentation in yeast. Under what condition a similar process takes place in our body that leads to muscle cramps? [2010 (T-I)] Ans: Yeast breakdown glucose (food) into ethyl alcohol and carbon dioxide and release energy during fermentation. Under anaerobic (no oxygen) a similar process takes place in our body that leads to muscle cramps. 7. Differentiate between tropic and nastic movements in plants. Give one example of each. [2009] Ans: Nastic movements are non directional responses to stimuli such as temperature and heat. These are kind of movements do not depend on direction of stimulus such as seismonastic, chemonastic, etc. Example of seismonastic movement is movement of Venus fly trap. Tropic movement is the response to stimuli that comes from one direction. It is a directional movement. If the movement of the plant part is towards the stimulus, then it is known as positive tropism. If the movement of the plant part is away from the stimulus, then it is known as negative tropism. For example phototropism, Geotropism etc. 8. Name the hormone secreted by human testes. State its functions. Ans. Hormone secreted by human testes. Testosterone function of testosterone is the development of secondary sexual characters in males like growth of hair, hoarse voice, moustaches etc. 9. Write the name and the functions of any two parts of the hind brain. Ans: Hindbrain: It consists of three regions, namely, a) Cerebellum: It is present at the posterior part of the brain. It is responsible for precise and accurate voluntary actions as well as for maintaining the posture and balance of the body. It is considered as the seat of equilibrium of the body. b) Pons : It lies above the medulla oblongata and acts as a bridge carrying sensory and motor impulses between the brain and the spinal cord. c) Medulla oblongata : It is the posterior most part of the brain and is called the brain stem. It has reflex centres to control involuntary actions like heart beat, blood pressure, breathing movements, coughing, sneezing, salivation, vomiting, etc. 10. How does our body maintain blood sugar level? [2010 (T-I) Ans: Pancreas is just below the stomach. They secrete insulin which helps to regulate blood sugar levels when there is deficiency of sugar in blood the cells send information to the pancreas then it secretes more enzymes which regulates it.When insulin is not secreted properly we get diabetes and we take injections of insulin.
SHORT ANSWER QUESTIONS (3 Marks) 11. A compound of iodine is compulsorily added to common salt in small quantity. (a) Why is it important for us to have iodised salt in our diet. (b) Name the disease caused by its deficiency. (c) Write symptom of the disease. [2010 (T-I)] Ans: (a) It is important to have iodized salt in our diet because iodine is required for the synthesis of a hormone called thyroxin. Thyroxin is a very important hormone required metabolism, growth and development of body and brain. Iodine deficiency can result in various disorders like goitre, so it is necessary to consume iodized salt. (b)Goitor is caused by its deficiency (c) The neck of person appear to be swellen. 12. What is reflex action? Describe the steps involved in reflex action. [2009] Ans: Reflex Action is defined as an unconscious, automatic and involuntary response of efforts, i.e., muscles and glands, to a stimulus, which is monitored through the spinal cord. Mechanism of Reflex Action: It involves the following steps: (i)Receptor organ like skin perceives the stimulus and activates a sensory nerve impulse. (ii)Sensory organ carries message in the form of sensory impulse to the spinal cord. (iii)The spinal cord acts as modulator. The neurons of spinal cord transmit the sensory nerve impulse to motor neuron. (iv) Motor nerve conducts these impulses to the effectors like leg muscles which responds by pulling back the organ away from the harmful stimulus. 13. What is âhydrotropismâ? Describe an experiment to demonstrate âhydrotropismâ? [2009] Ans: The growth of the root of plant in response to water or moisture Experiment: 1. Take two plastic troughs say A and B Fill each one of them with two-thirds of soil 3. Place the seedling in the soil in trough A 4 Place the similar seedling in trough B, place a small clay pot inside the soil. 5. Water the soil in the trough A daily and uniformly 6. Do not water the soil in trough B, but put some water in the clay pot placed in the soil. 7. Leave both the troughs for a few days. On examining the roots later, it will be found that the root in trough B has bent towards the clay pot that is source of water. Roots in trough A grew normally straight. Thus roots show the hydrotropism. 14. What is âphototropismâ? How does it occur in plants? Describe an activity to demonstrate phototropism. [2009] Ans: The growth movements in plants in response to light as stimulus is said to be phototropism Activity: To demonstrate phototropism in plants. Requirements: A potted plant, Procedure: Take a potted plant and keep it in the sunlight in a horizontal position and observe the growth of roots and shoots. Observation: The shoots of the plant grow towards sunlight and roots away from sunlight Conclusion: Roots are negatively phototropic and shoots are positively phototropic 15. Name a hormone secreted by :a) pancreas b)pituitary c)thyroid. state one function of each of the hormone. Ans: Thyroxin (secreted by thyroid gland) The hormone called thyroxin helps in coordinated growth. It regulates carbohydrate, fat, and protein metabolism in our body. The deficiency of this hormone results in the enlargement of the thyroid gland or goitre. Growth hormone (GH) (secreted by the pituitary gland) Growth hormone (GH) is involved in the growth and development of the human body. The secretion of this hormone should be properly maintained in the body. Over secretion of this hormone results in abnormal growth of the body known as gigantism. On the other hand, its low secretion results in dwarfism. Insulin (secreted by pancreas) The pancreas secretes a hormone called insulin, which regulates the blood sugar level in the human body. It increases the permeability of the cell membrane for glucose and accelerates the passage of glucose into the cells from the bloodstream. LONG ANSWER QUESTIONS (5 Marks) 16. (a) Name two hormones secreted by pancreas. Write one function of each hormone. (b) How does our body respond when adrenalin is secreted into the blood. (c) Write an example to explain feedback mechanism for regulation of hormonal secretion. [2010 (T-I)] Ans: (a) Two hormones secreted by pancreas are insulin and glucagon. Both regulate the levels of glucose in our body.Glucagon helps in elevating the amount of glucose in the blood while insulin decreases the level of glucose in the blood stream. (b) When someone is in danger or in emergency then adrenal gland secrete adrenaline hormone. It is secreted directly into the blood and is transported to different parts of the body. It speeds up the heartbeat and hence supplies more oxygen to the muscles. This results in increasing breathing rate and blood pressure which enable them to fight with such urgent situation. (c) Feedback means that some element in the physiological response to a hormone feeds back to the endocrine gland either directly or indirectly and affects its secretion rate. The feedback may be negative or positive. For example insulin regulates the amount of blood glucose. When the level of blood glucose is high, insulin secretion is turned on by the pancreas which acts on target tissues like liver to convert excess sugar into glycogen. When the blood glucose concentration is normal the insulin secretion is stopped. 17. (a) Draw the structure of a neuron and label the following on it.Nucleus, Dendrite, Cell body and Axon (b) Name the part of neuron: (i) where information is acquired. (ii) through which information travels as an electrical impulse. [2008] Ans: (b) The information that is acquired is received by the neuron at the dendrites and then the information travels in the form of impulse to cell body and then to Axon. Later when it reaches to synapse it is converted to chemical form. 18. Name the two main organs of our central nervous system. Which one of them plays a major role in sending command to muscles to act without involving thinking process? Name the phenomenon involved. Ans. Two main organs of our central nervous system are: Brain and spinal cord. Spinal cord sends the command to muscles to act without involving thinking process. This phenomenon is known as reflex action. 19. Name the hormone secreted by human testes. State its functions. Ans. Hormone secreted by human testes. Testosterone function of testosterone is the development of secondary sexual characters in males like growth of hair, hoarse voice, moustaches etc. 20. Name the plant growth hormone which is synthesised at the shoot tip.Explain breifly why does a plant bend towards light during its growth. Ans: The plant growth hormone that is synthesized is the shoot tip is Auxin. The growth of a plant towards the light source is known as phototropism. It occurs in plants due to the hormone auxin which is highly light sensitive. As sunlight falls on one side of the shoot, auxin gets stimulated and generally it diffuses to the shaded portion of the plant. It starts elongating the cells of the shaded portion. Thus the shaded portion grows and elongates more than the illuminated part. As a result the curvature of the plant stem tip bends towards the light. Ch. 7 - Control and Coordination class 10 Trendsetter solved CBSE Test paper-01 Ch. 7 - Control and Coordination class 10 Trendsetter solved CBSE Test paper-02 Ch. 7 - Control and Coordination class 10 Trendsetter solved CBSE Test paper-03
6 Comments
anita
15/8/2015 12:04:37 pm
Really very helpful!
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Saksham
3/9/2017 03:04:15 pm
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Shein
10/9/2017 04:50:53 pm
Tq so much it is really helpful
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