OCE 1001 Chapter 1

Current scientific knowledge indicates that the most likely origin of most of Earth's oceans was due to ________.

water vapor released from volcanic outgassing

The study of the structure of the sea floor and how the sea floor has changed through time is an example of ________ oceanography.

Geological

What element(s) are found in high concentrations in oceanic crust?

Iron, Magnesium

What happened to the nebular gas that remained from the formation of the planets and their satellites?

It was blown away by the solar wind.

Who left Spain in September 1519 and became the first person to complete a circumnavigation of the globe when he returned to Spain three years later?

Juan Sebastian del Caño

Which of the following is Earth's rigid layer that includes the crust plus the topmost portion of the mantle?

Lithosphere

What is a nebula?

a large, diffuse cloud of dust and gas in space

According to the fossil record on Earth, the earliest-known life-forms lived in sea floor rocks about 3.5 ________ years ago.

billion

Evidence suggests that the Sun and the rest of the solar system formed about five ________ years ago.

billion

One of the reasons that free oxygen in our atmosphere is important to the development and maintenance of life on Earth is because oxygen:

can form ozone and block some UV radiation.

The separation of the Earth into layers while it was molten was the result of the:

differing densities of the elements that make up the Earth.

The study of the structure of the sea floor and how the sea floor has changed through time is an example of ________ oceanography.

geological

A cometary model of the formation of Earth's ocean must include the chemical difference between the ________ in comet ice and that in Earth's water.

hydrogen

The important contribution to navigation made by Eratosthenes in the third century BC was __________.

a reasonably accurate calculation of the circumference of our planet

Earth's current atmosphere supports animal life because __________.

plant photosynthesis provides oxygen that is critical for aerobic respiration

Which of the following ideas support our current scientific understanding of the development of life on Earth? Choose all that apply.

- The "prebiotic soup" of the primitive oceans provided favorable conditions for life to develop. -As life evolved it significantly changed Earth's environment. -Primitive life likely existed without the need for oxygen. - Early organisms evolved into more-complex organisms over geologic time.

Mantle

- contains a weak layer below the lithosphere - contains rock rich in magnesium and iron

Core

- contains iron and nickel - both liquid and solid components

Rocks in which layer(s) of Earth are rigid?

- inner core - mesosphere -lithosphere

Crust

- is earth's stiff rigid rocky shell - solid part of this layer has a relatively homogeneous composition while another part is composed of many rock types

Which statement(s) below correctly describe differences between oceanic and continental crust?

-Continental crust is thicker than oceanic crust. -Continental crust floats higher on the mantle than oceanic crust. -Continental crust is mainly composed of granite, whereas oceanic crust is mainly composed of basalt.

Of the following statements about density stratification, which is/are true? Choose all that apply.

-Density stratification has caused the highest-density material to be found at Earth's core. -The origin of Earth's oceans and atmosphere are a result of density stratification. -Outgassing is a direct result of density stratification. -Density stratification has caused Earth's internal structure to be layered.

Which of the following statements is/are true regarding Earth's core?

-Earth's core is composed of two layers that differ in physical properties. -The core is composed of mainly iron and nickel, with some sulfur. -The outer core is liquid because it is so hot.

Which of the following statements is/are true regarding Earth's oceans?

-Earth's ocean is one big interconnected body of water. -The Southern Ocean is one of the least-studied areas on planet Earth. -NASA satellites fly over Antarctica.

Which of the following ideas support our current scientific understanding of the development of life on Earth? Choose all that apply.

-Primitive life likely existed without the need for oxygen. -The "prebiotic soup" of the primitive oceans provided favorable conditions for life to develop. -As life evolved it significantly changed Earth's environment. -Early organisms evolved into more-complex organisms over geologic time.

The average depth of the world's oceans is approximately ________.

3,682 meters (12,080 feet)

Earth is about:

4.6 billion years old

Archeological evidence suggests that boat technology was developed about ________ years ago.

40,000

When did our Solar System begin to form?

5 billion years ago

How did our Solar System begin to form?

A large cloud of dust and gas began to contract under the force of gravity.

Radioactive materials can sometimes be used to determine the:

Ages of rocks

Oceanic crust is primarily:

Basalt

Earth's atmosphere became oxygen rich about 2.45 ________ years ago.

Billion

Trilobites were dominant during which geologic period?

Cambrian

What are the reaction products of respiration?

Carbon dioxide, water

The first person we are aware of who determined the circumference of the Earth using trigonometry and the angle of sunlight at Alexandria, Egypt, was:

Eratosthenes

Which of the following is Earth's liquid iron-nickel layer?

Outer core

What happens during radioactive decay?

Parent isotopes turn into daughter isotopes

The study of the transmission of light and sound in the oceans is an example of ________ oceanography.

Physical

Which ocean is the shallowest ocean in the world?

The Arctic Ocean

Plate tectonics and evolution, which are held with a high degree of confidence because of rigorous testing and verification, are examples of:

Theories

How do plants and animals gain the energy needed to carry out cellular functions?

They utilize the energy in sugar.

According to the Geologic Time Scale, which selection lists the correct order of coexistence, from earliest to latest?

Trilobites and amphibians, insects and dinosaurs, dinosaurs and birds, flowering plants and fishes, humans and reptiles

The nebular hypothesis suggests that:

all bodies in the solar system formed from an enormous gas cloud.

Earth's early atmosphere most likely included:

carbon dioxide, water vapor, ammonia, and methane.

Although Earth's oceans have existed since early in the formation of the planet, its ________ must have changed.

chemical composition

Earth's second atmosphere formed from ________.

outgassing

What are the reaction products of photosynthesis?

oxygen gas and sugar

What is the scientific definition of half-life?

the amount of time over which the number of parent isotopes decreases by half

Where did the energy of the Sun come from originally?

thermal energy that was converted from the gravitational energy of the original nebula collapse

Compared to continental crust, oceanic crust is generally __________.

thinner, denser, darker in color, and at lower elevations

The explorer who advanced oceanography by introducing systematic soundings, or depth measurements, was __________

James Cook

What is the basis for relative positions of Earth's physical layers?

material density, with the least-dense material on the surface and the most-dense material in the center