Without specialised equipment, humans would be lost in these deep-sea habitats, so how do fish make it seem so easy? Much of this is due to a biological phenomenon known as electroreception the ability to perceive and act upon electrical stimuli as part of the overall senses. This ability is only found in aquatic and amphibious species because water is an efficient conductor of electricity.
One fascinating use of electroreception has been observed between the weakly electric fish. When two such electric fish meet in the ocean using the same frequency, each fish will then shift the frequency of its discharge so that they are transmitting on different frequencies. Doing so prevents their electroreception faculties from becoming jammed.
Electroreception can also play an important role in animal defences. Rays are one such example. Young ray embryos develop inside egg cases that are attached to the sea bed. The embryos keep their tails in constant motion to pump water and allow them to breathe through the egg’s casing. If the embryo’s electroreceptors detect the presence of a predatory fish in the vicinity, however, the embryo stops moving (and in doing so, ceases transmitting electric currents) until the predator has moved on.
Many people fear swimming in the ocean because of sharks. Sharks hunt with extraordinary precision. They initially lock on to their prey through a keen sense of smell. As the shark reaches the proximity of its prey, it tunes into electrical signals that ensure a precise strike on its target. This sense is so strong that the shark even attacks blind by letting its eyes recede for protection. In areas where shark attacks on humans are likely to occur, scientists are exploring ways to create artificial electroreceptors. These would disorient the sharks and repel them from swimming beaches.
Infer the advantage that aquatic or amphibious species have over human beings. Answer in about 40 words.
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Solution and Explanation
A possible use for electroreception that will benefit humans is to:
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- Use water as it is an efficient conductor of electricity.
- Act on electrical stimuli.
- Change electrical frequency to prevent it from being jammed.
- Jam electrical frequencies.
The Correct Option is B
Solution and Explanation
Explain in about 40 words the use of electroreception between the weakly electric fish.
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Solution and Explanation
Identify a young ray embryo from the following:
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- It fears electric signals.
- It keeps its tail in constant motion.
- It stations itself on land.
- It disorients sharks.
The Correct Option is B
Solution and Explanation
Complete the sentence appropriately: A shark hunts with accuracy because \(\_\_\_\_\_\_\_\).
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Solution and Explanation
Why does a shark recede its eyes when it attacks?
Solution and Explanation
In areas where shark attacks on humans are likely to occur, scientists:
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- suggest putting barriers.
- are exploring ways to create artificial electroreceptors.
- suggest blinding them.
- are exploring ways to warn swimmers.
The Correct Option is B
Solution and Explanation
State True or False.
The title – ‘Understanding Electroreception and its Uses is Significant for Human Beings’ is appropriate for this passage.
The title – ‘Understanding Electroreception and its Uses is Significant for Human Beings’ is appropriate for this passage.
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Solution and Explanation
Top Questions on Reading Comprehension
Read the extract and complete the activities given below:
Family can be classified into two types: joint family and nuclear family. In the joint family along with parents and children other members like grandparents, uncles, aunts, cousins, etc. are included. In such family, socialization of children is quicker. Tasks are shared. Responsibilities are shared.
Establishment of emotional bonds are common leading to mental security. Members learn adjustment. But sometimes there are conflicts and misunderstandings among family members. Children do not get complete attention from their parents.
On the contrary nuclear family consists of parents and their children. So we see flexibility in parental roles. Parents share their responsibilities. Parent child relationships are very intimate. Full attention is paid on children’s personality development. But children lack in making adjustments. Children get too much attention from their parents and so they become demanding and selfish.
Parenting styles do influence children’s behaviour. The best known research on parenting style is Diana Baumrind’s early studies of pre-school children and their parents. She proposed three parenting styles : permissive, authoritarian and authoritative.
Permissive parents are inconsistent in their behaviour. So children of such parents become dependent, immature.
Authoritarian parents are rigid and punitive in nature. Children of such parents become unfriendly, unsocial and uninvolved. Parents provide food and shelter to their children but they neglect them and become emotionally detached. That leads to indifferent, rejecting behaviour on the part of the children.
Authoritative parents encourage independence, they set limits and goals, they are firm in their behaviour. This kind of parenting style makes children self-reliable, independent and develop social skills.- Maharashtra Class XII - 2026
- English
- Reading Comprehension
Read the extract and complete the activities given below:
At length Soapy reached one of the avenues to the east where the glitter and turmoil was but faint. He dragged himself toward Madison Square, for the homing instinct survives even when the home is a park bench.
But, on an unusually quiet corner, Soapy came to a standstill. Here was an old church, quaint and rambling and gabled. Through one violet-stained window a soft light glowed, where, no doubt, the organist loitered over the keys, making sure of his mastery of the coming Sabbath Anthem. For there drifted out to Soapy’s ears sweet music that caught and held him transfixed against the convolutions of the iron fence.
The moon was above, full and radiant; vehicles and pedestrians were few; sparrows twittered sleepily in the eaves or a little while the scene might have been a country churchyard. And the anthem that the organist played cemented Soapy to the iron fence, for he had known it well in the days when his life contained such things as mothers and roses and ambitions and friends and immaculate thoughts and collars.
The conjunction of Soapy’s receptive state of mind and the influences about the old church brought a sudden and wonderful change in his soul. He viewed with rising horror the pit into which he had tumbled, the degraded days,
unworthy desires, dead hopes, wrecked faculties and base motives that made up his existence. And also in a moment his heart responded thrillingly to this strange mood. A strong impulse moved him to battle with his desperate fate. He would pull himself out of the mire and would make a man of himself again; he would conquer the evil that had enslaved him. There was time; he was young yet; he would resurrect his old eager ambitions and pursue them without faltering. Those solemn but sweet organ notes had set up a revolution in him. Tomorrow he would go into the roaring downtown district and find work. A fur importer had once offered him a place as driver. He would be somebody in the world. He would .....
Soapy felt a hand laid on his arm. He looked quickly around into the impassive face of a policeman.
“What are you doin’ here?” asked the officer.
“Nothin’,” said Soapy.
“Then come along,” said the policeman.
“Three months on the island,” said the Magistrate in the Police Court the next morning.- Maharashtra Class XII - 2026
- English
- Reading Comprehension
Read the following passage carefully:
(1) A recent survey conducted by an independent research firm sought to measure levels of happiness among youth aged 16–24 years in seven countries. The findings revealed some intriguing insights into what makes today’s youth happiest, as well as which factors influence their overall well-being. In India, an overwhelming majority of the youth reported feeling satisfied with their lives, with 87% rating their overall happiness as ‘high’ or ‘very high.’ Financial security was identified as the primary source of happiness for 66%, followed by family support (89%), having a purpose in life (50%), and work or studies (40%). Unfortunately, 65% reported feeling stress related to academic performance or workload, while 25% reported feeling lonely. These figures point to a need for increased mental health support among India’s youth.
(2) These surveys also revealed that family support is an important source of contentment for young people across countries. In Europe, 59% of respondents said that their families were a major source of happiness; in France this figure was 67%, and 63% in Germany. In North America, 64% rated family as an important factor for well-being in Canada, while 61% did so in the United States. Similarly, 89% of survey respondents in India named family support as a major contributor to their overall contentment level.
(3) It is clear that stress has a significant impact on the happiness of today’s youth. The findings suggest that young people need better resources to manage their mental health and well-being. This may include access to counselling services, mindfulness activities and support groups to help them cope with challenging circumstances. It is also important to provide financial support so as to reduce some of the economic pressures.
(4) In India, 65% of youth surveyed reported feeling anxious about their academic performance or workload, while 25% felt lonely. These figures are especially significant given how important family support is for young people’s overall contentment.
Answer the following question, based on the above passage:- CBSE Class XII - 2024
- English
- Reading Comprehension
- Read the following passage carefully:
(1) As a young adult, life can be stressful and overwhelming at times. Juggling among school, work, social life, and other responsibilities, it can be easy to feel alone and disconnected from the world around us. Dogs are the ultimate companions for anyone looking to alleviate stress and loneliness. We’ll explore many reasons why dogs make the best companions for young adults.
(2) Unconditional love: Dogs are known for their loyalty and love for their owners, no matter what. They don’t judge us, criticize us, or hold grudges against us. No matter how flawed or imperfect we may be, our dogs will always love us unconditionally. This kind of unwavering support and affection can be incredibly comforting for young adults struggling to find their place in the world.
(3) Social connection: Dogs are great ice-breakers and conversation starters. Whether you’re walking them in the park, taking them to the dog beach, or simply hanging out at home, dogs have a way of bringing people together. For young adults who may feel isolated or disconnected from their peers, having a dog by their side can be a great way to connect with others and form new friendships.
(4) Increase physical activity: Dogs require regular exercise in order to stay healthy and happy. This means that young adults who own dogs are more likely to engage in physical activity themselves. Whether it’s going for a run, playing frisbee, or simply taking a leisurely stroll, getting out with your dog can be a great way to boost your mood and energy levels.
(5) Emotional support: Dogs are also great emotional support animals for those struggling with mental health issues such as anxiety and depression. Their presence alone can provide a sense of calm and comfort, and their ability to sense their owner’s emotions can be incredibly comforting. For young adults dealing with mental health challenges, having a dog as a companion can be a life-changing experience.
(6) Improve responsibility and self-care: Owning a dog also comes with a great deal of responsibility and self-care. Dogs require regular feeding, grooming, exercise, and attention, which can be a great way for young adults to develop a sense of responsibility and self-discipline. Additionally, having a dog as a companion can encourage young adults to take better care of themselves, such as making sure they get enough sleep, eat healthy, and engage in regular exercise.
(7) For all these reasons and more, dogs make fantastic companions for young adults. Whether you’re looking for emotional support, social connection, increased physical activity, or simply someone to love and be loved by, a dog can provide all these things and more. So the next time you’re feeling stressed or overwhelmed, consider finding a furry friend to take on the world with you.
Answer the following questions, based on the above passage:
- CBSE Class XII - 2024
- English
- Reading Comprehension
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