Class 10 Science Chapter 6
Control and Coordination
Important Questions

Here are some critical Chapter 6 Control and Coordination problems for Class 10 Science. These inquiries are intended to aid students in studying for and performing well on the CBSE Class 10 Science Examination 2023–24. Students can clear up their concerns and be ready for the exams by practising different types of questions. By answering these questions, you'll increase your confidence while also sharpening your problem-solving abilities.

Introduction

In Chapter 6, "Control and Coordination," of Class 10 Science, students explore the intricacies of control mechanisms within living organisms. This chapter delves into the nervous system, elucidating its role in coordinating various bodily functions. Additionally, it examines the intriguing concept of coordination in plants and the pivotal role of hormones in animals, unveiling the remarkable ways in which organisms maintain harmony and respond to their environments.

Class 10 Control and Coordination Important Questions and Answers

Q1. The growth of tendrils in pea plants is due to:

Options

(a) Effect of gravity
(b) Effect of chemicals
(c) Rapid cell division in tendrillar cells that are away from the support
(d) Rapid cell division in tendrillar cells in contact with the support

Ans. (C)

Explanation:
‍Tendrils are growths of some plants that resemble hair or extremely fine threads and are seen on the stems and leaves of plants known as climbing plants.Rapid cell division in the tendril cells that are not attached to the support is what causes the tendril to expand in pea plants.Vine and liana (climbing plants) employ tendrils, which are thin stem- or petiole-like structures, to wrap around or hook support.Due to this requirement for support, anytime tendrils come into contact with or touch an item, the side they are touching grows slowly while the side they are touching opposite is shown to grow extremely quickly.Cells on the opposing side rapidly divide as a result.This aids in adhering and prevents the tendril from flowing with the wind, causing it to bend to the side where it meets the item.

Q2. Cretinism results due to:

Options

(a) Excess secretion of growth hormone
(b) Under secretion of thyroxin
(c) Excess secretion of adrenaline
(d) Under secretion of growth hormone

Ans. (b)

Explanation:
‍Cretinism is a disorder in children due to the hyposecretion of thyroid hormone. Cretinism leads to dwarfism with serious mental retardation and the individuals are called cretins.Thyroxine is a major hormone that is produced by the thyroid gland and contains iodine.The deficiency of iodine in the diet causes less secretion of thyroxine causing cretinism.

Q3. Taking the example of heart beat, justify the antagonistic action of the sympathetic and the parasympathetic nerves.

Explanation:
Sympathetic nerves accelerate the heart rate whereas parasympathetic nerves retard the heart rate as both the functions of sympathetic and parasympathetic nerves are antagonistic so we can say that they are opposite to each other in action.

Q4. Why do stem and root show unilateral growth towards light and earth’s gravity respectively?

Explanation:
Stem is positively phototropic and the root is positively geotropic. Plant hormone auxin is synthesised at the root tips as well as by the shoot apex. In stem growth is more at the shaded region due to more accumulation of auxins on that side as a result shoot bends towards light. Whereas in root, growth is more on the light receiving side as auxins get accumulated on the shaded side of the root tip which inhibits the growth of that side. So, there is greater growth in the upper side resulting in growth of root apex towards earth’s gravity.

Q5. Answer the following questions:
(a) Using the following words below, construct a reflex arc. Sensory nerves, receptor, effector, stimulus, brain or spinal cord, response, motor neurons.
(b) Imagine what would happen if your neurons were disc shaped?
(c) Pancreas is both endocrine and exocrine in nature. Suppose the exocrine part becomes damaged then how will it affect your body?
(d) Choose the incorrect word from the following and replace it with the correct word:
(i) Pancreas is called the master gland.
(ii) Iron is needed for production of Thyroxine.

Explanation:
(a) Stimulus → Receptor → Sensory nerves → Brain or spinal cord Motor nerves → Effector → Response.
(b) Transfer of messages with efficiency across a long distance would have been affected if the neurons were disc shaped.
(c) Digestion of food will be hampered as the exocrine part of the pancreas produces digestive juices that help in digestion in the small intestine.
(d) (i) Pancreas is the incorrect word replaced by pituitary gland.
(ii) Iron is the incorrect word replaced by iodine.

CBSE Class 10 Science Chapter wise Important Questions

Conclusion

oswal.io offers a thorough set of questions for learning the topic in a better way if you're looking to further practise and improve your grasp of the concepts covered in the chapter.

Frequently Asked Questions

Q1: What does the "Control and Coordination" chapter in Grade 10 CBSE Science encompass?

Ans: The "Control and Coordination" chapter in Grade 10 CBSE Science explores the mechanisms through which living organisms regulate and synchronize their functions. It delves into topics such as the nervous system, coordination in plants, and the role of hormones in animals, shedding light on how organisms maintain balance and respond to their surroundings.

Q2: Write the main functions of the following :
(a) sensory neuron
(b) cranium
(c) vertebral column
(d) motor neuron.

Ans: (a) Sensory neurons occur in sense organs and receive stimuli through their dendrites. The sensory neurons transmit impulses towards the central nervous system (brain and spinal cord) with the help of their axons.
(b) Cranium : The bones of cranium or brain box protect the brain from mechanical injury.
(c) Vertebral column : Major function of the vertebral column is protection of the spinal cord and carries the weight of the upper body.
(d) Motor neuron: The dendrites of these neurons synapse with axons of interneurons in the central nervous system. They transmit impulses from the central nervous system towards effectors (muscles or glands). The latter respond to stimuli.

Q3: Why does the flow of signals in a synapse from the axonal end of one neuron to the dendritic end of another neuron take place but not in the reverse direction? Explain.

Ans: At the synapse, (functional junction between neurons) axon terminal comes in close proximity to the dendron terminal of the next neuron. Axon terminal is expanded to form a pre-synaptic knob and the other dendrite terminal forms post- synaptic depression.In between the two, lies a narrow fluid filled space called synaptic cleft. As the nerve impulse reaches the presynaptic knob, the synaptic vesicles get stimulated to release neurotransmitters in the synaptic cleft. The neurotransmitter molecules diffuse across the gap to come in contact with the postsynaptic membrane. In this way, nerve impulse passes across the minute gap to stimulate the dendron of other neurons. The synapse acts as a one-way valve to conduct impulse in one direction only. This is so because a chemical substance called neurotransmitter is secreted only on one side of the gap, i.e., on the axon's side. It carries impulse across the synapse and passes it to the dendron of the other neuron. In this way, impulses travel across the neurons only in one direction, i.e., from the axon of one neuron to the dendron of another neuron through a synapse. ‍

Q4: “Reflex arcs continue to be more efficient for quick responses”. Justifying this statement gives reason.

Ans: Reflex action is an automatic and spontaneous response to a stimulus. The pathway taken by nerve impulses and responses in a reflex action is called a reflex arc. It consists of the receptor, sensory nerve (afferent), spinal cord, motor nerve (efferent) and effector (muscles or glands). Reflex arc is evolved in animals because the thinking process of the brain is not fast enough. Reflex arc enables the body to give quick responses to harmful stimuli so that chances of damage to the body are decreased. It also prevents overloading of the brain, so it prevents fatigue. Many animals have very little or none of the complex neuron network needed for thinking. So, it is likely that the reflex arc has evolved as an efficient way of functioning in the absence of true thought processes. However, even after complex neuron networks have come into existence, reflex arcs continue to be more efficient for quick responses.

Q5: State one example of chemotropism.

Ans: Growth of pollen tube towards the ovule due to chemical stimulus during the process of fertilisation in a flower is an example of chemotropism.