Qtr. 1 Lesson 1: Our World At A Glance

Question 1

This model describes our universe forming from a sudden and rapid expansion from which all known matter is said to have emerged.

Answer 1

Big Bang model

Question 2

As the universe began to stabilize, temperatures gradually decreased and particles began to coalesce, forming _____. These _____, in turn, began to form the elements that would become the foundation of matter in our universe.

Answer 2

atoms

Question 3

The first heavenly bodies formed small knots in great gas clouds that became _____.

Answer 3

galaxies

Question 4

An important discovery which greatly supports the Big Bang model is the discovery of _____.

Answer 4

cosmic background radiation

Question 5

It is the most widely accepted model of the formation and evolution of our solar system.

Answer 5

Nebular Hypothesis

Question 6

The ___ is the dominant astronomical object in our system, composing 99.9% of the entire mass of the solar system.

Answer 6

Sun

Question 7

The ____ is situated in the most optimal distance from the sun—not too close as to experience extreme temperatures and radiation, and not too far away as to become too cold.

Answer 7

Earth

Question 8

Other objects such as the dwarf planets ___, ___, and ___, asteroids, meteors, and comets are also within our solar system.

Answer 8

Pluto, Eris, and Ceres

Question 9

At present, several _____ orbit our planet, with a number of them orbiting the vast expanse of our solar system as probes that study the other planets and other astronomical objects.

Answer 9

man-made satellites

Question 10

_____ is the study of the origins and eventual fate of the universe. Cosmologists look at how the universe evolves and the natural laws that keep it in order.

Answer 10

Cosmology

Question 11

_____ is the study of celestial objects and other interstellar phenomena.

Answer 11

Astronomy

Question 12

_____ is a branch of astronomy that studies physical properties of celestial objects, their behaviors, and interactions.

Answer 12

Astrophysics

Question 13

_____ is a massive system composed of stars, interstellar objects, and dust clouds. This system contains several star systems and clusters.

Answer 13

Galaxy

Question 14

_____ refers to groups of galaxies bound together in a loose or tight formation often displaying the same pattern of movement across the universe.

Answer 14

Cluster

Question 15

_____ is a large group of clusters. These are among the largest structures in the universe.

Answer 15

Supercluster

Question 16

_____ is an interstellar cloud of dust and gas in the universe. Stars and planets were formed in nebulas.

Answer 16

Nebula

Question 17

_____ is a Greek word that means “wanderer” or “wandering star”

Answer 17

Planet

Question 18

The conditions of Earth upon its formation about 4.5 years ago is described as “_____”.

Answer 18

hellish

Question 19

Scientists have described the Eartg as being in the “_____” in the solar system, where the conditions were sufficient to encourage the emergence of life on the planet.

Answer 19

“habitable zone”

Question 20

About 2.5 million years ago, the surface of the Earth became more solid and stable, and within a few million years several developments occurred which rendered the Earth more habitable.

Answer 20

True

Question 21

The early oceans played an important part in changing the early climate.

Answer 21

True

Question 22

The first signs of life emerged from these oceans, one-celled organisms called _____.

Answer 22

prokaryotes

Question 23

_____ is a single cell organism which include bacteria. These organisms are able to survive environments with harsh conditions, such as high temperature and salinity.

Answer 23

Prokaryotes

Question 24

A number of early organisms called cyanobacteria produced food through _____.

Answer 24

photosynthesis

Question 25

_____ —also called blue-green bacteria or blue-green algae. These organisms use photosynthesis in their food production, releasing oxygen as a by-product.

Answer 25

Cynobacteria

Question 26

Oxygen that reached the upper atmosphere reacted with the ultraviolet light from the Sun and split into separate atoms which reacted to form _____.

Answer 26

ozone

Question 27

The interactions between the inner core and the molten layers of the Earth created the _____.

Answer 27

magnetic field

Question 28

The earliest continents, _____ and _____, formed three billion years ago, were smaller than Australia.

Answer 28

Vaalbara and Ur

Question 29

_____ was considered the first supercontinent which was formed about 1 billion years ago from fragments of earlier landmasses.

Answer 29

Rodinia

Question 30

_____, formed 300 million years ago, was the second supercontinent, and the most well-known of the ancient landmasses. During this period, life was beginning to develop and evolve on the surface of the Earth.

Answer 30

Pangaea

Question 31

Around 200 million years ago, Pangaea split into two landmasses—_____ and _____. The further drifting of these two landmasses created the continents as we know them today.

Answer 31

Laurasia and Gondwanaland

Question 32

_____ contained the landmasses that formed Europe, Asia, and North America.

Answer 32

Laurasia

Question 33

_____ gave rise to South America, Africa, Antarctica, Australia, the Indian subcontinent, and Arabia.

Answer 33

Gondwanaland