Kerala SSLC · Biology · Class 10
Sensations and Responses: Important Questions with Answers
These are 10 important multiple-choice questions from the Kerala SSLC Biology chapter “Sensations and Responses” (Kerala SCERT syllabus). Each one shows the correct answer and a short explanation of why it is right. Try answering before you read the answer. ExamSummary has 10 practice questions on this chapter in total.
Q1.In a typical neuron, in which direction does the nerve impulse travel?
- A)From axon to dendrite
- B)From cell body to axon
- C)From dendrite to cell body to axon
- D)From axon to cell body to dendrite
Answer: C) From dendrite to cell body to axon
The nerve impulse travels from the dendrites, which receive signals, to the cell body where processing occurs, and finally down the axon to transmit the signal to the next neuron or effector.
Q2.Which part of the brain is primarily responsible for maintaining posture and balance?
- A)Cerebrum
- B)Medulla Oblongata
- C)Cerebellum
- D)Thalamus
Answer: C) Cerebellum
The cerebellum is located at the back of the brain and controls voluntary movements, coordination, and balance, ensuring smooth muscle activity.
Q3.What is the correct sequence of events in a reflex action?
- A)Effector -> Sensory Neuron -> Spinal Cord -> Motor Neuron
- B)Receptor -> Sensory Neuron -> Spinal Cord -> Motor Neuron -> Effector
- C)Motor Neuron -> Spinal Cord -> Sensory Neuron -> Effector
- D)Receptor -> Motor Neuron -> Spinal Cord -> Effector
Answer: B) Receptor -> Sensory Neuron -> Spinal Cord -> Motor Neuron -> Effector
A reflex action begins when a receptor detects a stimulus, sending a signal via a sensory neuron to the spinal cord, which then activates a motor neuron to stimulate the effector.
Q4.Which cells in the retina are responsible for vision in dim light?
- A)Cone cells
- B)Rod cells
- C)Ganglion cells
- D)Optic nerve cells
Answer: B) Rod cells
Rod cells are highly sensitive to light and allow us to see in low-light conditions, whereas cone cells are responsible for color vision and detail in bright light.
Q5.In the human ear, which structure converts sound vibrations into electrical impulses?
- A)Eardrum
- B)Ossicles
- C)Cochlea
- D)Auditory Nerve
Answer: C) Cochlea
The cochlea contains hair cells that transform mechanical sound vibrations into electrical nerve impulses, which are then sent to the brain via the auditory nerve.
Q6.Which part of the brain controls involuntary actions like heart rate and breathing?
- A)Cerebrum
- B)Cerebellum
- C)Medulla Oblongata
- D)Hypothalamus
Answer: C) Medulla Oblongata
The medulla oblongata regulates vital involuntary functions such as heartbeat, respiration, and blood pressure to maintain homeostasis.
Q7.What is the small gap between two neurons called where chemical transmission occurs?
- A)Synapse
- B)Node of Ranvier
- C)Myelin Sheath
- D)Axon Terminal
Answer: A) Synapse
A synapse is the junction between two neurons where neurotransmitters are released to transmit signals across the tiny gap known as the synaptic cleft.
Q8.Which part of the eye adjusts the size of the pupil to control light entry?
- A)Cornea
- B)Iris
- C)Lens
- D)Retina
Answer: B) Iris
The iris is the colored part of the eye containing muscles that contract or relax to change the pupil size, regulating the amount of light entering the eye.
Q9.Voluntary actions are primarily controlled by which part of the central nervous system?
- A)Spinal Cord
- B)Cerebrum
- C)Medulla
- D)Cranial Nerves
Answer: B) Cerebrum
The cerebrum is the largest part of the brain and is responsible for higher functions including voluntary muscle movement, thinking, and reasoning.
Q10.If you touch a hot object, which receptors in your skin detect the heat first?
- A)Mechanoreceptors
- B)Thermoreceptors
- C)Photoreceptors
- D)Chemoreceptors
Answer: B) Thermoreceptors
Thermoreceptors are specialized sensory receptors located in the skin that respond to changes in temperature, allowing the body to detect heat or cold.