marine biology quiz

📚 Quick Study Guide

• 🌊 Buoyancy: An object floats if the buoyant force (upward force exerted by a fluid) is equal to or greater than the object's weight. Archimedes' principle states the buoyant force is equal to the weight of the fluid displaced by the object.
• 💧 Pressure: Pressure in the ocean increases with depth. The formula for pressure is: $P = P_0 + \rho g h$, where $P_0$ is the atmospheric pressure, $\rho$ is the density of seawater, $g$ is the acceleration due to gravity, and $h$ is the depth.
• 🔊 Sound in Water: Sound travels much faster in water (around 1500 m/s) than in air (around 343 m/s). The speed of sound in water is affected by temperature, salinity, and pressure.
• 💡 Light in Water: Light is absorbed and scattered as it travels through water. Red light is absorbed first, followed by orange, yellow, green, and violet. This affects the distribution of marine life at different depths.
• 🌡️ Temperature and Density: Seawater density is affected by temperature and salinity. Colder, saltier water is denser and tends to sink. This drives ocean currents.
• 🌀 Ocean Currents: Driven by wind, temperature differences, salinity differences, and the Earth's rotation (Coriolis effect). They play a crucial role in heat distribution around the globe.
• 📈 Waves: Waves transfer energy through the water. Wave properties include wavelength, frequency, amplitude, and speed. Deep-water waves are not affected by the ocean floor, while shallow-water waves are.

🧪 Practice Quiz

1. Which of the following best describes Archimedes' principle?
   1. A. An object floats if its density is less than water's.
   2. B. The buoyant force on an object is equal to the weight of the fluid it displaces.
   3. C. Pressure increases with depth.
   4. D. Light is absorbed exponentially with depth.
2. What happens to water pressure as depth increases?
   1. A. It decreases linearly.
   2. B. It remains constant.
   3. C. It increases linearly.
   4. D. It decreases exponentially.
3. Approximately how fast does sound travel in water?
   1. A. 343 m/s
   2. B. 1500 m/s
   3. C. 3.0 x 10^8 m/s
   4. D. 100 m/s
4. Which color of light is typically absorbed first in seawater?
   1. A. Blue
   2. B. Green
   3. C. Red
   4. D. Violet
5. What two primary factors affect the density of seawater?
   1. A. Pressure and depth
   2. B. Temperature and salinity
   3. C. Light and sound
   4. D. Waves and currents
6. What is the main driving force behind surface ocean currents?
   1. A. Tides
   2. B. Wind
   3. C. Temperature differences
   4. D. Salinity differences
7. What determines the speed of a shallow-water wave?
   1. A. Wavelength
   2. B. Water depth
   3. C. Wave height
   4. D. Wave period