Colour Blindness Reading Answers

Jan 20, 2023

Colour Blindness Reading Answers comprises 13 questions. Colour Blindness Reading Answers is taken from the book - Complete IELTS Bands 6.5-7.5 Student's Book with Answers. Colour Blindness Reading Answers comprises three types of questions: choose the suitable heading, write appropriate letters and match a phrase. Candidates are required to read the IELTS Reading passage to choose the suitable heading from the given list. Candidates need to thoroughly go through each paragraph to answer the statement given with the correct option that matches with it. For the last set of questions, candidates are supposed to match a phrase A, B or C in the box with the writer’s opinions. Candidates can gain proficiency on diverse topics like - Colour Blindness Reading Answers and more by undertaking IELTS Reading practice papers.

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Section 1

Read the Passage to Answer the Following Questions

Colour Blindness Reading Answers

Colour Blindness

Colour blindness results from an absence or malfunction of certain colour-sensitive cells in the retina. The retina is a neuro-membrane lining the inside back of the eye, behind the lens. The retina contains both rod cells (active in low light or night vision but which cannot distinguish colour) and cone cells (active in normal daylight, sensitive to colour). Cone cells, also called photoreceptors, are concentrated mostly in the central part of the retina, in an area called the macula. Cone cells provide clear, sharp colour vision. The cones contain light-sensitive pigments that are sensitive to the range of wavelengths. There are three different types of cones with one sensitive to short wavelengths, or the colour blue, one sensitive to medium wavelengths, or the colour green, and the other sensitive to higher wavelengths, or the colour red. All of these cells send information about colour to the brain via the optic nerve which connects to the1 retina at a point very close to the macula. Normal persons, referred to as trichromats, are able to match all colours of the spectrum by using a combination of these three fundamental colour sensitivities. Hence, the huge variety of colours we perceive stems from the cone cells' response to different compositions of wavelengths of light.

There are many types of colour blindness. When there are deficiencies in the cones, either at birth or acquired in other ways, the cones are not able to distinguish the particular wavelengths and thus, that colour range is seen differently. Those with defective colour vision have a deficiency or absence in one or more of the pigments. People with a deficiency in one of the pigments (the most common type of colour vision problem) are called anomalous trichromats. When one of the cone pigments is absent and colour is reduced to two dimensions, dichromacy occurs. These individuals normally know they have a colour vision problem and it can affect their lives on a daily basis. They see no perceptible difference between red, orange, yellow, and green. All these colours that seem so different to the normal viewer appear to them to be the same colour. Missing the cones responsible for green and red hues can also affect the sensitivity to brightness.

Most cases of colour blindness, about 99%, are inherited, resulting from partial or complete loss of function in one or more of the different cone systems and affect both eyes without worsening over time. The most common are red-green hereditary (genetic) photoreceptor disorders collectively referred to as "red-green colour blindness". It affects 8% of all males of European origin and 0.4% of all females. The gene for this is carried in the X chromosome. Since males have an X-Y pairing and females have X-X, colour blindness can occur much more easily in males and is typically passed to them by their mothers. In other words, females may be carriers of colour blindness, but males are more commonly affected. People with this disorder cannot identify red or green by itself but can if among a coloured group. Other forms of colour blindness are much more rare. They include problems in discriminating blues from yellows. Both colours are seen as white or grey. This disorder occurs with equal frequency in men and women and usually accompanies certain other physical disorders, such as liver disease or diabetes.

The rarest form of all is total colour blindness, monochromacy, where one can only see grey or shades of black, grey and white as in a black-and-white film or photograph. Monochromacy occurs when two or all three of the cone pigments are missing and colour and lightness vision is reduced to one dimension. Another term for total colour blindness is achromatopsia, the inability to see colour.

Inherited colour vision problems cannot be treated or corrected. Some acquired colour vision problems can be treated with surgery, such as the removal of a cataract, depending on the cause. Certain types of tinted filters and contact lenses may also help an individual to distinguish different colours better. Additionally, computer software has been developed to assist those with visual colour difficulties and those with mild colour deficiencies to learn to associate colours with certain objects and are usually able to identify colour in the same way as everyone else. One frequent problem encountered is with traffic lights, and worst of all, warning lights: colour-blind people always know the position of the colours on the traffic light - in most situations; red on top, yellow in the centre, green on the bottom. But warning lights present an entirely different problem. In this situation there is only one light; no top or bottom, no right or left, just one light that is either red or yellow.

Colour vision problems can have a significant impact on a person's life, learning abilities and career choices. On an everyday basis, there are some annoyances and frustrations: not being able to differentiate between green or ripe tomatoes when preparing food, for example, or buying clothes that to the 'normal' eye seem positively garish. However, people with colour vision problems usually learn to compensate for their inability to see colours. Although there is little or no treatment for colour blindness, most colour deficient persons compensate well for their defect and may even discover instances in which they can discern details and images that would escape normal-sighted persons. At one time the US Army found that colour-blind persons can spot camouflage colours in cases where those with normal colour vision are typically fooled.

Section 2

Solution and Explanation

Questions 14-20

Complete each sentence with the correct ending A - K from the box below.

Write the correct letter A - K in spaces 14-20 below.

A	can see better at night than during the day
B	cannot be treated by surgery
C	can affect men much more easily than women
D	can affect their sensitivity to bright lights
E	can see no colour at all, other than shades of black, grey and white
F	can see things that people with normal vision cannot
G	can have very dangerous consequences for colour-blind people.
H	can be acquired or inherited
I	can mean having to wear contact lenses.
J	cannot distinguish certain colours if they stand alone
K	can match all colours of the spectrum

Colour blindness can be caused by a birth defect, or

Answer: H- can be acquired or inherited
Supporting Sentence: the cones are not able to distinguish the particular wavelengths and thus, that colour range is seen differently.
Keywords: particular wavelengths, colour range
Keyword Location: Paragraph 2
Explanation: In paragraph 2, it mentions that when there are defects in the cones, either acquired via other means or present at birth. The cones are unable to discriminate between the specific wavelengths, and as a result, that colour spectrum is seen differently.

Surprisingly, some people who are colour blind

Answer: F- can see things that people with normal vision cannot
Supporting Sentence At one time the US Army found that colour-blind persons can spot camouflage colours in cases where those with normal colour vision are typically fooled.
Keywords: colour-blind persons, camouflage colours
Keyword Location: last paragraph
Explanation: In the last paragraph, it mentions that the majority of color-blind people adjust effectively for their deficiency. It may even find situations where they can make out details and visuals that would escape normal-sighted others, despite the fact that there is little to no therapy available. The US Army once discovered that color-blind people may recognise camouflage colours when individuals with normal colour vision are often misled.

People with hereditary colour blindness

Answer: B- cannot be treated by surgery
Supporting Sentence: The most common are red-green hereditary (genetic) photoreceptor disorders collectively referred to as "red-green colour blindness".
Keywords: red-green hereditary, photoreceptor disorders, "red-green colour blindness".
Keyword Location: Paragraph 3
Explanation: The most prevalent are red-green inherited (genetic) photoreceptor abnormalities, sometimes known as "red-green colour blindness," according to paragraph 3.

Because of our genetic make-up, colour blindness

Answer: C- can affect men much more easily than women
Supporting Sentence: females may be carriers of colour blindness, but males are more commonly affected.
Keywords: colour blindness
Keyword Location: Paragraph 4
Explanation: According to paragraph 4, boys are more likely than females to have colour blindness, which is normally passed on to them by their mothers. In other words, while women may have the gene for colour blindness, men are more likely to be afflicted.

Red-green genetic photoreceptor disorders mean that people

Answer: J- cannot distinguish certain colours if they stand alone
Supporting Sentence: People with this disorder cannot identify red or green by itself but can if among a coloured group.
Keywords: disorder cannot identify red or green
Keyword Location: Paragraph 4
Explanation: According to paragraph 4, individuals with this disease may recognise red or green when they are amid other colours but not on their own.

People with monochromacy

Answer: E- can see no colour at all, other than shades of black, grey and white
Supporting Sentence: can see no colour at all, other than shades of black, grey and white
Keywords: The rarest form of all is total colour blindness, monochromacy, where one can only see grey or shades of black, grey and white as in a black-and-white film or photograph.
Keyword Location: Paragraph 5
Explanation: The rarest type of colour blindness, or monochromacy, when a person can only perceive shades of black, grey, and white, like in a black-and-white movie or image, is mentioned in paragraph 5.

The inability to see certain lights

Answer: G- can have very dangerous consequences for colour-blind people.
Supporting Sentence: One frequent problem encountered is with traffic lights, and worst of all, warning lights: colour-blind people always know the position of the colours on the traffic light.
Keywords: warning lights: colour-blind
Keyword Location: Paragraph 6
Explanation: One common issue is with traffic lights, and worst of all, warning lights, as is stated in paragraph 6: People who are color-blind always recognise the colours on a traffic light in the following order: red at the top, yellow in the middle, and green at the bottom. However, warning lights present a very other issue. There is just one light in this circumstance, and it may either be red or yellow. There is no top or bottom, right or left.

Questions 21-23

Choose the correct letter A, B, C or D.

What causes colour blindness?

the absence of rod cells
the malfunction of rod cells
the malfunction of cone cells
the retina’s inability to detect light

Answer: C
Supporting Sentence: Cone cells provide clear, sharp colour vision.
Keywords: cone cells
Keyword Location: Paragraph 1
Explanation: As stated in paragraph 1, both rod cells, which are active in low light or night vision but are unable to perceive colour, and cone cells are found in the retina (active in normal daylight, sensitive to colour).

Which group of people are the least common?

people who cannot detect blues from yellows
anomalous trichromats
people with dichromacy
people with achromatopsia

Answer: D- people with achromatopsia
Supporting Sentence: can see no colour at all, other than shades of black, grey and white
Keywords: The rarest form of all is total colour blindness, monochromacy, where one can only see grey or shades of black, grey and white as in a black-and-white film or photograph.
Keyword Location: Paragraph 5
Explanation: The rarest type of colour blindness, or monochromacy, when a person can only perceive shades of black, grey, and white, like in a black-and-white movie or image, is mentioned in paragraph 5.

What would colour-blind people consider an everyday nuisance?

not being able to identify the colour of warning lights
not being able to tell an apple from a tomato
not being able to cook
not being able to buy matching clothes

Answer: D-not being able to buy matching clothes
Supporting Sentence: On an everyday basis, there are some annoyances and frustrations: not being able to differentiate between green or ripe tomatoes when preparing food
Keywords: green or ripe tomatoes
Keyword Location: Paragraph 7
Explanation: On a daily basis, there are certain annoyances and disappointments, such as not being able to tell if tomatoes are green or ripe while making meals or purchasing clothing that, to the 'normal' sight, appears positively gaudy.

Questions 24-26

Complete the diagram below.

Choose NO MORE THAN TWO WORDS from the passage for each answer.

24 ________

25 ________

26 ________

Answer: optic nerve
Supporting Sentence: The retina is a neuro-membrane lining the inside back of the eye, behind the lens.
Keywords: neuro-membrane
Keyword Location: Paragraph 1
Explanation: The retina is a neuro-membrane that lines the interior of the back of the eye, behind the lens, as stated in paragraph 1. Both rod cells, which are active in low light or night vision but are unable to perceive colour, and cone cells are found in the retina (active in normal daylight, sensitive to colour).

Answer: retina
Supporting Sentence: All of these cells send information about colour to the brain via the optic nerve which connects to the1 retina at a point very close to the macula.
Keywords: optic nerve
Keyword Location: Paragraph 2
Explanation: According to paragraph 2, all of these cells communicate information about colour to the brain through the optic nerve, which joins the retina at a location very near the macula.

Answer: macula
Supporting Sentence: Cone cells, also called photoreceptors, are concentrated mostly in the central part of the retina, in an area called the macula.
Keywords: photoreceptors, macula
Keyword Location: Paragraph 1
Explanation: According to paragraph 1, cone cells, which are also known as photoreceptors, are mostly located in the macula, a region in the centre of the retina.

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