Problem 82 - Objective Biology for NEET

Question

Which of the following is not a basic colour in trichromatic vision? (a) Red (b) Yellow (c) Green (d) Blue

Step-by-Step Solution

Answer

The basic colors in trichromatic vision are red, green, and blue. Therefore, yellow is not a basic color in trichromatic vision.

Step 1: Remember the basics of trichromatic vision

The approach to this problem is straightforward; there are no calculations or deductions necessary. What's important here is to remember that the name 'trichromatic' comes from 'tri-' showing there are three colors involved and '-chromatic' related to color. These colors are the primary colors the human eye uses to perceive all the others, which are red, green, and blue.

Step 2: Compare the options with the basic colors of trichromatic vision

Next, you should compare the options with the fundamental colors of the trichromatic color system. In the provided list, there are four options: red, yellow, green, and blue. Of these four, three are part of the basic colors in trichromatic vision, and one is not.

Step 3: Identify the color that is not basic to trichromatic vision

Based on the knowledge of the trichromatic color system, we can see that red, green, and blue are part of this system. However, yellow is not one of these primary colors, it's a secondary color created by combining the primary ones. Thus, yellow is the color that is not part of the basic colors in trichromatic vision.

Key Concepts

Primary Colors

In our exploration of colors, the concept of primary colors is fundamental, especially when considering trichromatic vision. Trichromatic vision relies on three primary colors: red, green, and blue. These colors are unique because they cannot be created by mixing other colors. Instead, they serve as the building blocks for all other colors our eyes can perceive.

These primary colors are used in various applications ranging from screens to art. When combined in different ways, they can create a wide array of colors. For instance:

• Mixing red and green light gives you yellow, a secondary color.
• Combining green and blue light yields cyan.
• Red and blue light produce magenta.

Understanding these basics helps us appreciate how our devices display colorful images and how artists mix colors for paintings.

Color Perception

Color perception is a fascinating process that occurs within our eyes as they interpret light. It all starts with visible light, which comprises different wavelengths corresponding to different colors. Our eyes have dedicated cells called cones, and they are sensitive to these specific wavelengths.

Humans typically have three types of cone cells:

• Cones that are sensitive to long wavelengths (red).
• Cones for medium wavelengths (green).
• Cones for short wavelengths (blue).

Trichromatic color vision arises from this basis in perception. By varying the activity of these cones, we perceive other colors, like yellow or purple. It's important to note that factors like lighting, surrounding colors, and even psychological aspects can influence color perception.

Thus, while genetically ingrained, our perception of color can vary widely.

Human Vision System

The human vision system is a complex yet marvelous adaptation that allows us to see the world in colorful detail. It involves not only the eyes but also the brain, which is responsible for processing visual information.

Here’s how it works:

• Light enters the eye through the cornea, bending to pass through the lens.
• From there, it reaches the retina, which houses the light-sensitive cells, including cones and rods.
• Cones are mainly responsible for color vision, while rods are more about detecting light intensity and enable seeing in low light.

The optic nerve plays a crucial role by transmitting signals from the retina to the brain, where they are interpreted as the images we see. This system enables humans to see and differentiate between millions of colors, making our perception vibrant and intricate.

It also accounts for various phenomena like afterimages and color blindness, demonstrating its sophistication and sensitivity.