1. Which colors of the visible light spectrum are most strongly absorbed by water molecules near the ocean's surface?
- A. Blue and violet
- B. Green and yellow
- C. Red and orange
- D. Ultraviolet and infrared
2. What is the direct cause of green and blue light being visible at greater ocean depths compared to other colors?
- A. Water reflects other colors at the surface.
- B. Water transmits these short wavelengths effectively.
- C. These wavelengths are amplified by salt in the water.
- D. Marine plants produce light in these colors.
3. A scuba diver brings a bright red object down to a depth of 100 meters, where little sunlight penetrates. Without using an artificial light, how will the object most likely appear?
- A. Bright red, as its natural color is permanent.
- B. A faint blue, as it can only reflect the available ambient light.
- C. Dark grey or black, because the red wavelengths needed to see its color were absorbed by the water far above.
- D. Vibrant green, due to a chemical reaction with saltwater at pressure.
4. The deep ocean appears blue to an observer primarily because water molecules...
- A. absorb blue light most strongly.
- B. are naturally blue-pigmented.
- C. scatter blue light more than they absorb it, allowing it to travel deeper and reflect back.
- D. convert red and green light into blue light through a process called fluorescence.
5. A research submarine needs to use an external lamp to see as far as possible in the deep ocean. Which color of light would be the most effective choice for maximum visibility distance?
- A. Red, because it contrasts most with the dark water.
- B. White, because it contains all the colors of the spectrum.
- C. Blue, because its short wavelength penetrates furthest through water.
- D. Yellow, because it is the brightest color to the human eye.
6. Based on the principle of selective absorption, which color of light from the sun penetrates the deepest into the open ocean?
- A. Red
- B. Yellow
- C. Blue
- D. Orange
7. Imagine a special camera that can only detect red wavelengths of light. If this camera were taken to a depth of 150 meters in the ocean during the day, what would it most likely record?
- A. A clear, red-tinted image of the surroundings.
- B. An almost completely black or dark image.
- C. A blurry image dominated by blue and green tones that the sensor misinterprets.
- D. A bright image of any bioluminescent creatures producing red light.
8. Why must a scientist use a submersible with its own white light source to observe the true colors of organisms at 200 meters?
- A. Because the natural sunlight at that depth lacks the red and yellow wavelengths needed to see those colors.
- B. Because the water is too murky with sediment for any sunlight to pass through at that depth.
- C. Because the intense pressure from the water above compresses the light waves, shifting all colors toward the blue end of the spectrum.
- D. Because only artificial light is strong enough to reflect off the microscopic scales of deep-sea fish.
9. If a hypothetical photosynthetic algae evolved to live at 100 meters deep, which wavelengths of light would it be most adapted to utilize?
- A. Red and orange light
- B. Infrared and ultraviolet light
- C. A full spectrum of white light
- D. Blue and green light
10. What scientific principle explains why the mixture of light colors changes as you descend deeper into the ocean?
- A. Light refraction
- B. Selective absorption
- C. Photosynthesis
- D. Bioluminescence