CONTROL AND CO-ORDINATION: Short Answer Type Question for Class 10th Chapter 10 JKBOSE/NCERT
Question 1. How do the tendrils help plants to cling to other objects?
Ans: Tendrils help plants cling to other objects by coiling around them. They have a sensitive tip that can detect touch or contact with a support structure. When the tip of a tendril comes into contact with an object, it starts coiling around it, providing support for the plant to climb or attach itself to the object.
Question 2. How many types of movements are shown by plants? Explain with examples.
Ans: Plants exhibit various types of movements, including:
Phototropism: The movement of a plant in response to light. For example, the growth of a plant towards a light source is positive phototropism, while growing away from light is negative phototropism.
Gravitropism: The response of a plant to gravity. Roots show positive gravitropism by growing towards gravity, while stems show negative gravitropism by growing against gravity.
Thigmotropism: The response of a plant to touch or physical contact with an object. Examples include the coiling of tendrils around support structures or the curling of tendrils around a trellis.
Hydrotropism: The movement of a plant in response to water. Roots exhibit positive hydrotropism by growing towards a water source.
Question 3. What are Phototropic movements? Give examples.
Ans: Phototropic movements are the directional responses of plants to light. When a plant perceives light from one direction, it initiates growth or movement towards or away from the light source. Examples of phototropic movements include:
Positive phototropism: The growth of plants shoots towards a light source, enabling them to receive more light for photosynthesis.
Negative phototropism: The growth of roots away from light, helping them to grow deeper into the soil for better nutrient absorption.
Question 4. What are phytohormones? Name any two phytohormones.
Ans: Phytohormones are chemical substances produced by plants that regulate various physiological processes. They act as chemical messengers, controlling growth, development, and responses to environmental stimuli. Two examples of phytohormones are:
Auxins: These hormones regulate plant growth, including cell elongation, apical dominance, and phototropism.
Gibberellins: These hormones are involved in stem elongation, seed germination, and flowering
Question 5. What do the squirrels experience when they are in scary situations?
Ans: When squirrels are in scary situations, they typically experience fear or a heightened state of alertness. They may exhibit behaviours such as freezing in place, increased heart rate, quick movements, or seeking shelter or escape routes to protect themselves from potential threats.
Question 6. Name the disease caused by the deficiency of iodine in our body. Write one of its symptoms.
Ans: The disease caused by the deficiency of iodine in our body is called goitre. One of its symptoms is the enlargement of the thyroid gland, resulting in a visible swelling in the neck area.
Question 7. Write the functions of the hypothalamus.
Ans: The hypothalamus performs several functions, including:
1. Regulation of body temperature
2. Control of hunger and thirst
3. Production and release of hormones that control the pituitary gland
4. Control of the sleep-wake cycle
5. Regulation of emotions and behaviour
6. Coordination of the autonomic nervous system responses, such as the fight-or-flight response.
Question 8. State two functions of auxins and gibberellins.
Ans: Functions of auxins:
1. Stimulating cell elongation and promoting growth in plant shoots.
2. Controlling phototropism by promoting growth towards light and inhibiting growth away from light.
Functions of gibberellins:
1. Promoting stem elongation and cell division.
2. Stimulating seed germination and flowering.
Question 9. Write the role of the nervous system in the body.
Ans: The nervous system plays a crucial role in the body by coordinating and regulating various physiological functions. Its main roles include:
1. Receiving and interpreting sensory information from the environment.
2. Sending motor commands to muscles and glands for movement and response.
3. Facilitating communication between different parts of the body.
4. Controlling and coordinating bodily functions, including heartbeat, digestion, and respiration.
5. Processing and storing information, enabling learning and memory.
Question 10. List the components of the nervous system.
Ans: The components of the nervous system include:
Brain: The central control centre of the nervous system.
Spinal cord: A long, cylindrical bundle of nerves that extends from the brain and transmits signals between the brain and the body.
Nerves: Bundles of specialized cells called neurons that transmit signals throughout the body.
Neurons: Individual nerve cells that transmit electrical signals.
Ganglia: Clusters of nerve cell bodies found outside the brain and spinal cord.
Receptors: Specialized structures that detect sensory stimuli, such as light, sound, or touch.
Question 11. Name five major senses of man.
Ans: The five major senses of humans are:
Vision (sight): The ability to perceive and interpret visual stimuli and light.
Hearing (audition): The ability to perceive and interpret sound vibrations.
Taste (gustation): The ability to perceive and interpret flavours of substances.
Smell (olfaction): The ability to perceive and interpret odours.
Touch (tactile sensation): The ability to perceive and interpret tactile stimuli, including pressure, temperature, and pain.
Question 12. Write two differences between exocrine and endocrine glands.
Ans: Differences between exocrine and endocrine glands:
Exocrine glands secrete their products into ducts that carry them to specific locations (e.g., sweat glands, salivary glands), while endocrine glands release their products (hormones) directly into the bloodstream.
Exocrine glands typically secrete substances with external functions (e.g., enzymes, sweat), while endocrine glands produce hormones that regulate internal bodily functions and target distant organs or tissues.
Question 13. How does chemical coordination take place in animals?
Ans: Chemical coordination in animals occurs through the endocrine system. The endocrine glands secrete hormones into the bloodstream, and these hormones travel to target cells or organs, where they bind to specific receptors. This binding triggers a response in the target cells, coordinating various physiological processes and maintaining homeostasis in the body.
Question 14. What is the difference between a reflex action and walking?
Ans: Reflex action and walking are different in the following ways:
Reflex action is an involuntary and rapid response to a stimulus while walking is a voluntary and coordinated movement.
Reflex actions are typically simple and automatic, controlled by the spinal cord, while walking involves complex motor planning and coordination by the brain.
Question 15. What are the parts of the forebrain?
Ans: The forebrain consists of several important structures, including:
Cerebral cortex: The outer layer of the brain responsible for higher cognitive functions, such as consciousness, perception, memory, and language.
Thalamus: Acts as a relay station for sensory information, directing it to the appropriate areas of the cerebral cortex.
Hypothalamus: Regulates various homeostatic processes, including body temperature, hunger, thirst, and hormone production.
Limbic system: Involved in emotions, memory, and motivation. It includes structures like the amygdala and hippocampus.
Basal ganglia: Plays a role in motor control and movement coordination.