Class 5 Science HOTS Questions - Nervous System

Q1: Situation: Mark was playing soccer when he suddenly tripped and fell. He noticed that his knee started hurting badly. Which part of the nervous system is responsible for making him feel pain in his knee?
(a) Central Nervous System
(b) Peripheral Nervous System
(c) Autonomic Nervous System
(d) Somatic Nervous System
Ans: (b)
The peripheral nervous system (PNS) includes nerves outside of the brain and spinal cord. It carries sensory information from the body's tissues and organs to the central nervous system (CNS) and sends motor commands back to the body. In this situation, the pain signals from Mark's knee are transmitted by sensory nerves (part of the PNS) to the CNS, making him feel pain.

Q2: Situation: Sarah was feeling very scared while watching a horror movie. Her heart was beating fast, and she felt sweaty. Which part of the nervous system is responsible for these physical reactions to fear?
(a) Central Nervous System
(b) Somatic Nervous System
(c) Sympathetic Nervous System
(d) Parasympathetic Nervous System
Ans: (c)
The sympathetic nervous system is a part of the autonomic nervous system that prepares the body for the "fight or flight" response in stressful situations, such as fear. It increases heart rate, dilates pupils, and triggers sweating, among other physical reactions, to prepare the body to deal with the perceived threat.

Q3: Situation: During a science class experiment, the teacher asked the students to touch a hot object briefly and then a cold object immediately afterward. Why did the students feel the cold object even colder than it was?
(a) Due to the activation of cold receptors
(b) Due to the activation of hot receptors
(c) Due to the activation of pain receptors
(d) Due to the activation of pressure receptors
Ans: (a)
The skin contains specialized receptors for temperature sensations, including cold and hot receptors. When the students touched the hot object first, it activated the hot receptors. Subsequently, when they touched the cold object, the cold receptors were more sensitive than usual due to the prior activation of hot receptors. This made the cold object feel even colder than its actual temperature.

Q4: Situation: Timmy had a habit of cracking his knuckles frequently. One day, his friend told him that cracking knuckles too often is bad for the nervous system. Is this statement true or false?
(a) True
(b) False
Ans: (b)
Cracking knuckles does not directly harm the nervous system. The "popping" sound that occurs when knuckles are cracked is due to the sudden release of gas bubbles from the joint fluid. However, it might irritate people around due to the sound and could potentially cause some issues with the joints over time, but it does not harm the nervous system.

Q5: Situation: Lily has been having trouble sleeping at night and feels tired during the day. Her teacher explained that a part of the brain regulates sleep-wake cycles. Which area of the brain is responsible for this?
(a) Cerebellum
(b) Hypothalamus
(c) Medulla Oblongata
(d) Occipital Lobe
Ans: (b)
The hypothalamus, a small but crucial part of the brain, plays a significant role in regulating sleep-wake cycles. It is involved in controlling various physiological functions, including sleep, hunger, body temperature, and hormone regulation.

Q6: Situation: Jackson experienced a severe injury that resulted in temporary paralysis of his legs. Which part of the nervous system is likely to be affected in this case?
(a) Central Nervous System
(b) Peripheral Nervous System
(c) Autonomic Nervous System
(d) Somatic Nervous System
Ans: (d)
The somatic nervous system is responsible for voluntary movements and sensory information between the central nervous system and the muscles, skin, and joints. Temporary paralysis of the legs indicates that there is likely a problem with the somatic nervous system, specifically in the motor neurons that control leg movements.

Q7: Situation: Maria is playing her favorite video game, and she notices that her heart rate and breathing rate increase as she reaches higher levels in the game. Which part of the nervous system is responsible for these changes?
(a) Central Nervous System
(b) Somatic Nervous System
(c) Parasympathetic Nervous System
(d) Sympathetic Nervous System
Ans: (d)
The sympathetic nervous system prepares the body for action and stress, commonly known as the "fight or flight" response. In this situation, as Maria gets more engaged and excited during intense gaming, the sympathetic nervous system activates, leading to increased heart rate and breathing rate to supply oxygen and energy to her body for the gaming challenges.

Q8: Situation: While riding his bicycle, Jack accidentally stepped on the front brake instead of the rear brake, causing the bicycle to stop abruptly and throwing him off balance. Which part of the nervous system was responsible for this quick reaction?
(a) Central Nervous System
(b) Somatic Nervous System
(c) Autonomic Nervous System
(d) Peripheral Nervous System
Ans: (b)
The somatic nervous system controls voluntary movements and reflex actions. When Jack accidentally stepped on the front brake, the somatic nervous system rapidly triggered a reflex action that caused him to lose balance and attempt to regain control.

Q9: Situation: A group of students went on a field trip to a museum. In one exhibit, they were asked to touch various objects and guess their textures while blindfolded. Which part of the nervous system is primarily responsible for their sense of touch?
(a) Central Nervous System
(b) Peripheral Nervous System
(c) Somatic Nervous System
(d) Sensory Nervous System
Ans: (d)
The sensory nervous system, which is part of the peripheral nervous system, is responsible for processing sensory information from the environment and transmitting it to the central nervous system (brain and spinal cord). In this situation, the students' sense of touch is being processed by sensory receptors in their skin and transmitted to the brain to interpret the different textures they feel.

Q10: Situation: Emily was waiting at the bus stop on a chilly winter morning. She noticed that her body shivered involuntarily to generate heat and keep her warm. Which part of the nervous system is responsible for this involuntary response?
(a) Central Nervous System
(b) Somatic Nervous System
(c) Autonomic Nervous System
(d) Sympathetic Nervous System
Ans: (c)
The autonomic nervous system is responsible for regulating involuntary functions of the body, including shivering, sweating, and heart rate. In cold weather, the autonomic nervous system activates shivering as a mechanism to generate heat and maintain body temperature.