Worksheets12.6 Earth's First Life
Total questions: 13
Worksheet time: 12mins
What organic compounds are essential for DNA and RNA to form?
hydrogen sulfide
ammonia and methane
carbon dioxide
oxygen
amino acids
The most common Precambrian fossils are ________, layered mounds of calcium carbonate.
prokaryotes
chert
trilobites
eukaryotes
stromatolites
Scientists have found evidence that life existed at least 3.5 billion years ago ________.
in northern Siberia
on the Gulf Coast
throughout North and South America
in Kenya
in several locations around the world
Which of the following is would be considered a hypothesis for how life began?
) Methane and hydrogen sulfide from deep-sea hydrothermal vents and hot springs like those at Yellowstone National Park provided the necessary materials.
Asteroids and comets brought amino acids to Earth.
Outgassing and related volcanic materials brought proto amino acids to the surface of the earth.
Methane and ammonia in the early atmosphere combined with the help of lightning or ultraviolet light to produce the first amino acids.
A distinctive characteristic of prokaryotes is ________.
their thick cell walls that separate the DNA from the rest of the cell
their lack of a separation between the DNA and the rest of the cell
their oxygen based metabolism
their methane based metabolism
their ability to produce sugars
Which type of bacteria thrive in environments that lack free oxygen?
aerobic
placental
anaerobic
foraminifera
photosynthetic
A class of organic molecules that provide the primary structural material for life and contribute to the functioning of cells.
(a)
A cell or an organism such as bacteria whose genetic material is not enclosed in a nucleus.
(a)
Structures that are deposited by algae and consist of layered mounds of calcium carbonate.
(a)
An organism whose genetic material is enclosed in a nucleus; plants, animals, and fungi are eukaryotes.
(a)
What group of organic compounds combine to form proteins and is therefore necessary for life as we know it?
(a)
What group of organisms are thought to have produced stromatolites?
(a)
Compare prokaryotes with eukaryotes.
