A summary of what i learned recently I

1. What is Marine Science?

It is the study of organisms of the sea.

2. Why do we need to study Marine Biology?

71% of our Earth is the ocean. Our life probably originated in the sea, and marine life helps determine the very nature of our planet. Through the study of marine biology, we can have a better understanding of the relationship between aquatic animals and the environment. How do they influence each other? How do these marine animals that we share on a planet live in the ocean? We could learn a lot from marine life and create a better world.

3. Discuss the importance of ocean explorations and give an example of an

expedition and its discovery or contribution to studying oceans today.

The ocean’s contributions to the world are significant. Oceans can regulate the climate, produce oxygen for living organisms, provide food for both marine animals and humans, help people to transport, and offer resources for us such as submarine oil… The world can’t live without the oceans. There are a lot of things in the ocean that we haven’t discovered yet. Besides, we are using ocean resources, so we have to know whether it’s sustainable to keep exploiting the ocean resources. Therefore, it is crucial to learn ocean, to be aware of the limit of oceans, and more importantly, we need to make efforts to protect the oceans. A lot of people in history contribute to the study of oceans. James cook, for example, was one of the first ocean explorers. He created the first dependable charts and brought back plant and animal specimens. He also found that eating citrus (containing vitamin C) could prevent scurvy. Therefore, he proved that through careful observation, scientific discoveries can be made by nonscientists.

4. Cite some modern marine biology and research tools or technology used for studying oceans.

Sonar- to locate objects, generate water images…

Submersible (AUVs & ROVs)- helps to explore inhospitable environments such as the deep sea

Crittercam- can take photos for scientists to study animals’ behavior

5. What are the layers of the Earth?

• Crust
• Mantle

Upper mantle

Lower mantle

• Core

Outer core

Inner core

6. Differentiate the oceanic crust from the continental crust.

• Different composition:

Oceanic crust- basalt    Continental crust- granite

• Different density:

Oceanic crust- 2.9 g/cm3     Continental crust -2.7g/cm3

Different location:

• Oceanic crust- mid-ocean ridges

Continental crust- the outermost layer of Earth’s lithosphere

7. Explain the Theory of Continental Drift.

Alfred Wegener was the one who proposed this idea. He pointed out that the continents had drifted. Matching mountain ranges across oceans, glacial ages, climate evidence and fossil distributions such as Mesosaurus were all his evidence to support his idea. However, some scientists objected to his idea because it was too far-fetched and contrary to the laws of physics.

8. What is the evidence of seafloor spreading?

• Earth’s magnetic field
• Age of the sea floor (younger sea floor is near the mid-ocean ridge. Sea floor’s age is growing with increasing distance from the mid-ocean ridge)
• The pattern of worldwide earthquakes

9. Describe the three types of plate boundaries.

• Divergent

Two plates move toward each other

• Convergent

Two plates are moving separated

• Transform

Two plates just move past each other

10. Describe asthenosphere, mid-ocean ridge, and trench.

• The asthenosphere is a layer beneath the lithosphere with the partially-molten mantle.
• Mid-ocean ridge

When two continents are separated, some regions rise, like a mountain. Volcanoes and earthquakes occur along with this active rift area.

• Trench

The trench is like a gap or crack in the ocean. It is the deepest part of the ocean.

Mariana trench is the deepest ocean trench.