1. What were the early theories regarding the origin of the Earth, and who proposed the Nebular Hypothesis? (Pg. 2) Page 13
2. Using the balloon analogy, explain what the “expanding universe” means. What is the limitation of this analogy? (Pg. 2) Page 13
3. What is Hoyle’s concept of steady state, and which concept is currently favoured by scientists? (Pg. 3) Page 14
4. How was the layered structure of the Earth (lithosphere) developed? Explain the process of differentiation. (Pg. 4) Page 15
5. How do modern scientists refer to the origin of life, and what evidence do we have for early life on Earth? (Pg. 5) Page 16
6. Describe the three stages in the development of the universe according to the Big Bang Theory. (Pg. 2-3) Page 13-14
7. What are the three stages in the development of planets as described in the chapter? (Pg. 3-4) Page 14-15
8. List and explain the three stages in the evolution of the Earth’s present atmosphere. (Pg. 4-5) Page 15-16

The term ‘Nebular Hypothesis’ is associated with which philosophers/scientists? (Pg. 2)

What is the most popular theory regarding the origin of the universe? (Pg. 2)

Approximately how long ago did the Big Bang event take place? (Pg. 3)

A light year is a measure of: (Pg. 3)

What was the nature of the Earth’s surface initially? (Pg. 4)

Which process contributed water vapour and gases to the early atmosphere through the Earth’s interior? (Pg. 4)

Which of the following gases flooded the atmosphere around 2,000 million years ago? (Pg. 5)

Life on Earth is believed to have begun to evolve around how many years before the present? (Pg. 5)

(Exercise) Which figure represents the age of the Earth? (Pg. 5)

(Exercise) Which one is NOT related to the formation/modification of the present atmosphere? (Pg. 5)

The process through which planets were formed from a cloud of gas and dust is called ______. (Pg. 2) Page 13

Who provided evidence that the universe is expanding? (Pg. 2) Page 13

What was the temperature and density of the initial “tiny ball” of matter before the Big Bang? (Pg. 3) Page 14

What are the initial differences in the early universe that led to the formation of galaxies? (Pg. 3) Page 14

The very large cloud of hydrogen gas that leads to galaxy formation is called a ______. (Pg. 3) Page 14

In the second stage of planet formation, small rounded objects formed by cohesion are called ______. (Pg. 4) Page 15

The early atmosphere largely contained water vapour, nitrogen, carbon dioxide, methane, ammonia and very little of free ______. (Pg. 4) Page 15

(Exercise) The process through which the material inside the Earth got separated into different layers is called ______. (Pg. 5) Page 16

(Exercise) The gases which initially formed the Earth’s primordial atmosphere were ______ and helium. (Pg. 5) Page 16