Space, fossils, & Geological time scales

Question 1

What is an Astronomical Unit used for?

Answer 1

Unit used to measure distances within the solar system.

Question 2

How many Km is an astronomical unit equal to?

Answer 2

1AU = 150,000,000 Km (150 Million Km)

Question 3

What is a Light Year used for?

Answer 3

Unit used to measure big distances outside the solar system.

Question 4

How many Km is a light year equal to?

Answer 4

1LY = 9,460,000,000,000 Km (9,460 Billion Km)

Question 5

What six conditions make the development of life possible?

Answer 5

1. The Habitable Zone
2. A Circular Orbit
3. An Atmosphere
4. The Ideal Mass
5. Water
6. A Lithosphere

Question 6

What is Pasteurization?

Answer 6

The partial sterilization of liquids, to destroy disease-causing bacteria and other undesirable organisms.

Question 7

What is a fossil?

Answer 7

The remains of animals and plant that are generally found in sedimentary rocks.

Question 8

What is another word for layers in sedimentary rock?

Answer 8

Strata.

Question 9

Why are Stratigraphic layers important?

Answer 9

It allows science to explain the various events that happened in Earth’s history.

Question 10

What are the three techniques scientists can use to date strata?

Answer 10

• Superposition
• Relative Dating
• Absolute Dating

Question 11

What is Superposition?

Answer 11

Superposition says that the oldest layer is always at the bottom and that the youngest layer is always at the top.

Question 12

What is relative dating?

Answer 12

Technique used to determine the order in which events took place, this method helps determine which layer is older than the other, when a fault is running through them.

Question 13

What is absolute dating?

Answer 13

Process by which the age of the fossils or rock layer can be determined by the amount of carbon-14 present in the rocks.

Question 14

What are the major eras?

Answer 14

• The Precambrian era (lasted 4 billion years)
• The Paleozoic era (lasted 300 million years)
• The Mesozoic era (lasted 185 million yeas)
• The Cenozoic era (started 65 million years ago)

Question 15

When does a new era occur?

Answer 15

New eras occur with mass extinctions or mass population expansions.

Question 16

What are the main events in the Precambrian era?

Answer 16

• The formation of the first continent, Rodinia.
• Appearance of Prokaryotes (cells with no nuclei) and bacteria.
• Appearance of bacteria that can perform photosynthesis & release oxygen
• Appearance of Eukaryotes (cells with a nucleus); worms, soft coral, jellyfish, etc
• Appearance of Ediacaran fauna (animals capable of digesting & reproducing)

Question 17

What are the main events in the Paleozoic era?

Answer 17

• Earth separates into four continents
• Appearance of animals with spines & shells
• Appearance of first land plants (mosses, mushrooms, lichens)
• Very cold climate causes a mass extinction, half of the animals disappear
• Jawed fish
• Appearance of trees
• First amphibians
• Extinction due to various events caused 70% of marine species to disappear
• Conifers & small reptiles
• Largest mass extinction caused by glaciation, volcanic eruptions, destruction of the ozone layer, 96% of marine species disappear and 75% of land species disappear.

Question 18

What are the main events in the Mesozoic era?

Answer 18

• Warm climate favors the appearance of the large reptiles/dinosaurs
• Mass extinction causes 50% marine life to disappear
• Appearance of birds & small mammals
• Appearance of flowering plants
• Mass extinction due to a meteorite causes the disappearance of dinosaurs

Question 19

What are the main events in the Cenozoic era?

Answer 19

• Mammals
• Appearance of megafauna
• Appearance of hominids (first humans)
• Extinctions of megafauna caused by hunting and diseases by humans