A recent study by researchers from Basel University and Munich Technical University challenges prior beliefs about the influence of different light colours on the human body’s internal clock and sleep-wake rhythm. Unlike a previous study conducted on mice, this one suggests,
that light colour may be less critical for the internal clock than originally thought.
Vision involves a complex process of perceiving various light wavelengths as colours and brightness in the brain. Photoreceptors in the retina convert light into electrical impulses, transmitted to ganglion cells in the retina and to the visual cortex in the brain. Specialised ganglion cells play a significant role in the internal clock, being sensitive to short-wavelength light at around 490 nanometers, perceived as blue. When activated by short-wavelength light, these cells signal “it’s daytime” to the internal clock.
To explore the influence of light colour on the internal clock, the researchers exposed 16 healthy volunteers to blueish or yellowish light stimuli for one hour in late evening with a white light stimulus as a control condition. The light stimuli were designed to selectively activate the colour-sensitive cones in the retina, while maintaining consistent stimulation of the light-sensitive ganglion cells in all conditions. This allowed the researchers to directly check effects of light on the respective cone stimulation and, the colour of the light.
Contrary to the findings in mice, the study suggests that the colour of light, as encoded by the cones, may not significantly influence the human internal clock and sleep-wake rhythm. The current research contradicts the earlier finding that yellowish light had a stronger influence on the internal clock than blueish light. The results, published in “Nature Human Behaviour”, imply that while light intensity and exposure duration remain crucial factors, the colour of light may not play as significant a role in influencing sleep and circadian rhythms as previously believed.
What does the recent study by researchers from the University of Basel and the Technical University of Munich challenge?
- Sleep-wake rhythms in mice
- The impact of light colour on the internal clock
- Vision complexity in humans
- The effect of sleep-wake cycle
The Correct Option is B
Approach Solution - 1
Approach Solution -2
The study challenges the belief that light colour significantly impacts the internal clock and sleep-wake rhythm.
Context: The study in question examines the widely held belief that the colour of light plays a crucial role in regulating the body’s internal clock, also known as the circadian rhythm, and sleep-wake cycles. Many have assumed that different colours of light, particularly blue light, have significant effects on our sleep patterns.
Challenging the Existing Belief: Contrary to popular assumptions, the study suggests that light colour may not have as significant an effect on the internal clock as previously believed. The findings challenge the conventional understanding of how light interacts with our sleep-wake rhythm, prompting further investigation into other potential factors at play.
Implications of the Findings: If light colour does not significantly impact the circadian rhythm, other environmental or physiological factors may be more influential in regulating our sleep patterns. This could open new avenues for research on improving sleep quality through methods other than light exposure.
Final Thought: The study’s findings encourage a re-examination of current sleep research, emphasizing the need for a broader understanding of the complex mechanisms that govern our internal clocks and sleep-wake cycles.
What is the role of specialized ganglion cells in the internal clock, according to the passage?
- Transmitting electrical impulses to the visual cortex
- Converting light into electrical impulses
- Getting destabilized by the sleep-wake rhythms
- Reacting strongly to short-wavelength light
The Correct Option is D
Approach Solution - 1
Approach Solution -2
Specialised ganglion cells react to short-wavelength light (around 490 nm, perceived as blue), which signals “daytime” to the internal clock.
Context: Specialized ganglion cells in the retina are sensitive to short-wavelength light, particularly light around 490 nm, which is perceived as blue. This sensitivity plays a critical role in regulating the body’s internal clock, or circadian rhythm, signaling when it is "daytime."
Role of Ganglion Cells: These ganglion cells contain a photopigment called melanopsin, which is highly responsive to blue light. When exposed to light of this wavelength, the ganglion cells send signals to the brain, informing it that it is daytime and helping to synchronize the internal clock with the external environment.
Impact on the Internal Clock: The activation of these ganglion cells by short-wavelength light is crucial for maintaining the body’s circadian rhythm, which governs sleep-wake cycles and other biological processes. Exposure to blue light during the day helps keep the internal clock aligned with the natural day-night cycle.
Final Thought: The discovery of how ganglion cells react to short-wavelength light emphasizes the importance of light exposure in regulating our internal clocks. This understanding can help inform strategies to improve sleep quality and manage circadian rhythms, especially in the modern era of artificial lighting.
Why were the light stimuli designed to differentially activate colour-sensitive cones in the retina?
- To study the circadian rhythms
- To maintain consistent stimulation of ganglion cells
- To check the effect of light on the cone stimulation
- To explore vision complexity
The Correct Option is C
Approach Solution - 1
Approach Solution -2
The light stimuli were designed to activate cones and check the effect of light on cone stimulation while maintaining consistent ganglion cell activity.
Context: The study was designed to investigate how light stimuli affect cone stimulation in the retina while ensuring that ganglion cell activity remains constant. The aim was to understand the specific role of cones in response to light stimuli, separate from the effects on ganglion cells.
Activation of Cones: Cones are specialized photoreceptor cells in the retina responsible for color vision and visual acuity. By using light stimuli designed to specifically activate these cones, researchers were able to isolate the effects of light on cone function without interference from ganglion cell activity.
Maintaining Consistent Ganglion Cell Activity: Ganglion cells play a crucial role in transmitting visual information from the retina to the brain. In this study, the researchers carefully controlled light exposure to ensure that ganglion cell activity remained consistent, allowing them to focus solely on the cones' response to the stimuli.
Final Thought: This method of isolating cone stimulation while controlling ganglion cell activity helps provide clearer insights into the complex processes of visual perception and how different light stimuli affect various retinal cells.
What did the prior study on mice suggest about the impact of colour of light on the human internal clock and sleep-wake rhythm?
- The colour of light has a significant impact on both.
- The colour of light is not critical for sleep-wake rhythm.
- It has no influence on sleep patterns.
- It is mainly dependent on vision complexity.
The Correct Option is A
Approach Solution - 1
Approach Solution -2
The prior study on mice suggested that the colour of light significantly impacts the internal clock and sleep-wake rhythm.
Context: The previous research conducted on mice indicated that the colour of light plays a crucial role in regulating the internal clock, also known as the circadian rhythm, and the sleep-wake cycles. The study found that different light colours could influence the timing and quality of sleep.
Impact of Light Colour: The study suggested that exposure to specific colours of light, particularly blue light, could have a significant effect on the body’s internal clock. Blue light has been shown to promote alertness and regulate the sleep-wake cycle by influencing the production of melatonin, a hormone responsible for sleep.
Relevance to Sleep-Wake Rhythm: By affecting the internal clock, the colour of light can help align the sleep-wake rhythm with the natural day-night cycle. This has important implications for improving sleep quality and managing sleep disorders, particularly in environments with artificial lighting.
Final Thought: The findings from the prior study on mice underscore the potential significance of light colour in regulating circadian rhythms and improving sleep patterns. These results may lead to new strategies for optimizing light exposure to enhance sleep quality in humans.
What is the key implication of the research study’s results for our understanding of sleep and circadian rhythms?
- Colour of light is the sole determinant of sleep and circadian rhythms.
- Light intensity plays a crucial role in sleep and circadian rhythms.
- Light intensity and exposure duration are the secondary factors.
- Light colour may not play as significant a role as previously believed.
The Correct Option is D
Approach Solution - 1
Approach Solution -2
The study implies that light colour may not significantly impact sleep and circadian rhythms, shifting the focus to light intensity and exposure duration.
Context: Contrary to the common belief that light colour plays a major role in regulating sleep and circadian rhythms, the study suggests that light colour may not have as significant an impact as previously thought. Instead, the study shifts the focus to other factors like light intensity and exposure duration.
Impact of Light Intensity: The study highlights that the intensity of light, rather than its colour, might be a more critical factor in regulating sleep patterns. Brighter light could have a stronger effect on alertness and the suppression of melatonin, influencing the sleep-wake cycle.
Exposure Duration: In addition to intensity, the duration of light exposure plays an essential role in affecting the internal clock. Longer periods of light exposure, especially during the night, may disrupt sleep and circadian rhythms, while proper timing and shorter exposure may help synchronize the body's internal clock.
Final Thought: The study's findings suggest that we should reconsider the emphasis placed on light colour and focus more on managing light intensity and exposure duration to improve sleep quality and regulate circadian rhythms effectively.
Find a word from the passage that is similar in meaning to CATALYST.
- Stimuli
- Complex
- Encoded
- Internal
The Correct Option is A
Approach Solution - 1
Approach Solution -2
The word “stimuli” refers to something that triggers or initiates a response, similar in meaning to “catalyst.”
Context: The term "stimuli" refers to any factor or event that triggers a physiological or psychological response. It plays a critical role in initiating reactions in the body, similar to how a "catalyst" accelerates or facilitates a chemical reaction.
Meaning of Stimuli: Stimuli can be anything from light, sound, temperature, or even emotional triggers that cause a response in an organism. For example, the presence of light can stimulate the human eye, leading to visual perception.
Similarities with Catalyst: Just as a catalyst speeds up a chemical reaction without being consumed, a stimuli triggers a response or reaction without being permanently changed by it. Both words imply the initiation of a process or reaction.
Final Thought: The word “stimuli” closely aligns with “catalyst” in its meaning, as both involve triggering or initiating a response or reaction, whether in biological systems or chemical processes.
Top Questions on Reading Comprehension
“Why do they pull down and do away with crooked streets, I wonder, which are my delight, and hurt no man living? Every day the wealthier nations are pulling down one or another in their capitals and their great towns: they do not know why they do it; neither do I. It ought to be enough, surely, to drive the great broad ways which commerce needs and which are the life-channels of a modern city, without destroying all history and all the humanity in between: the islands of the past.”
(From Hilaire Belloc’s “The Crooked Streets”)
Based only on the information provided in the above passage, which one of the following statements is true?- GATE PH - 2025
- General Aptitude
- Reading Comprehension
“Why do they pull down and do away with crooked streets, I wonder, which are my delight, and hurt no man living? Every day the wealthier nations are pulling down one or another in their capitals and their great towns: they do not know why they do it; neither do I. It ought to be enough, surely, to drive the great broad ways which commerce needs and which are the life-channels of a modern city, without destroying all history and all the humanity in between: the islands of the past.” (From Hilaire Belloc’s “The Crooked Streets”)
Based only on the information provided in the above passage, which one of the following statements is true?
- GATE CE - 2025
- General Aptitude
- Reading Comprehension
- “His life was divided between the books, his friends, and long walks. A solitary man, he worked at all hours without much method, and probably courted his fatal illness in this way. To his own name there is not much to show; but such was his liberality that he was continually helping others, and fruits of his erudition are widely scattered, and have gone to increase many a comparative stranger’s reputation.”
(From E.V. Lucas’s “A Funeral”)
Based only on the information provided in the above passage, which one of the following statements is true?- GATE CE - 2025
- General Aptitude
- Reading Comprehension
- Read the excerpt from a Handicrafts Manual: ‘Advanced Knitting Techniques’ and answer the following questions by choosing the most appropriate answer.
THE FAIR ISLE METHOD: Fair Isle knitting is a traditional technique that involves using two or more colours of yarn in a single row to create intricate patterns and designs. This method requires careful tension management to ensure even stitches and prevent puckering. To begin, select your colours and cast on the desired number of stitches. As you knit, alternate between colours every few stitches, carrying the unused yarn along the back of the work. Mastering the Fair Isle technique allows you to create stunning visual effects in garments, accessories, and home textiles.
THE CONTINENTAL STYLE: The Continental knitting style, often referred to as “picking,” involves holding the yarn in the left hand while the right hand manipulates the needles. This method allows for greater speed and efficiency, particularly when working with complex patterns or multiple colours. To practice this style, start by casting on your stitches and using your left hand to tension the yarn. With each stitch, simply “pick” the yarn with your right needle, forming a quick and fluid motion. As you become comfortable with this technique, you may find that your overall knitting speed and comfort improve significantly.
THE SHORT-ROW TECHNIQUE: Short-row knitting is an advanced technique that allows for the creation of shaped garments, such as sleeves and shoulders, without the need for complex shaping. To make a sleeve using this technique, begin by casting on the required number of stitches. Work a portion of the row, then turn your work and return without completing the full row to create the “short rows” that shape the curves of the sleeve. To prevent holes at the turn, wrap the stitch before you turn your work. Repeat this process as needed to achieve the desired shaping and dimension of the sleeve. Once you have shaped the sleeve, you can then sew the side seams to connect the pieces of your garment and finally, complete the edges to ensure a clean finish. This method not only helps shape curves but also adds dimension to your piece, allowing you to enhance fit and style.- AILET BALLB (Hons.) - 2025
- English
- Reading Comprehension
- Read the following passage and answer the following questions by choosing the most appropriate answer.
The Story of Coffee
Coffee, a beloved beverage enjoyed by millions around the globe, has a rich and captivating history that spans centuries. The story of coffee begins in the ancient highlands of Ethiopia, where, according to legend, a goat herder named Kaldi discovered the stimulating effects of coffee beans. One day, Kaldi noticed his goats frolicking with unusual energy after eating red berries from a certain tree. Curious, he tried the berries himself and experienced a newfound alertness. This discovery soon spread to monasteries, where monks used it to stay awake during long hours of prayer. From Ethiopia, coffee cultivation and consumption spread to the Arabian Peninsula, particularly in Yemen, where the practice of roasting coffee beans and brewing the drink began to take shape. By the 15th century, coffee had become a popular beverage in the Islamic world, with coffee houses known as ‘qahveh khaneh’ emerging as social hubs for conversation, music, and intellectual exchange. These coffee houses became centers of culture and commerce, influencing the spread of coffee to Turkey and beyond, eventually reaching Europe. In Europe, coffee initially faced resistance from religious authorities who considered it a ‘Muslim drink’ and tried to ban it. However, its popularity persisted, and by the 17th century, coffee houses had sprung up in major European cities, becoming important gathering places for artists, writers, and thinkers. The stimulating effects of coffee were embraced during the Age of Enlightenment, where it was seen as a catalyst for intellectual discussion and innovation. The journey of coffee continued with the establishment of colonial plantations in tropical regions such as the Caribbean, Central and South America, and Southeast Asia. These plantations fuelled the global demand for coffee, transforming it from a regional specialty to a major commodity. The industrial revolution further accelerated coffee production and consumption, leading to innovations in coffee brewing methods and the development of instant coffee. In the modern era, coffee has evolved into a deeply ingrained part of daily life for people worldwide. Its cultural significance spans from the bustling cafes of Paris to the quiet coffee farms of Colombia. Today, coffee remains not only a popular beverage but also a symbol of social interaction, productivity, and enjoyment. Whether sipped slowly over a conversation with friends or grabbed hastily on the way to work, the story of coffee continues to unfold, intertwining with the histories and cultures of countless societies across the globe.- AILET BALLB (Hons.) - 2025
- English
- Reading Comprehension
Questions Asked in CUET exam
- Two resistances of 100 \(\Omega\) and 200 \(\Omega\) are connected in series across a 20 V battery as shown in the figure below. The reading in a 200 \(\Omega\) voltmeter connected across the 200 \(\Omega\) esistance is _______.
Fill in the blank with the correct answer from the options given below- CUET (UG) - 2024
- Current electricity
- A molecule X associates in a given solvent as per the following equation:
X ⇌ (X)n
For a given concentration of X, the van’t Hoff factor was found to be 0.80 and the
fraction of associated molecules was 0.3. The correct value of ‘n’ is:- CUET (UG) - 2024
- Solutions
- If $t = e^{2x}$ and $y = \ln(t^2)$, then $\frac{d^2 y}{dx^2}$ is:
- CUET (UG) - 2024
- Second Order Derivative
- The corner points of the feasible region determined by $x + y \leq 8$, $2x + y \geq 8$, $x \geq 0$, $y \geq 0$ are $A(0, 8)$, $B(4, 0)$, and $C(8, 0)$. If the objective function $Z = ax + by$ has its maximum value on the line segment $AB$, then the relation between $a$ and $b$ is:
- CUET (UG) - 2024
- Linear Programmig Problem
- If 75$\%$ of a first-order reaction gets completed in 32 minutes, the time taken for 50$\%$ completion of this reaction is:
- CUET (UG) - 2024
- Order of reaction