WELL DETAILED ANSWERS|LATEST
UPDATE!!!2025/2026|GUARANTEED
The rapid diversification of multicellular organisms occurred in the _______ eon. -
ANSWER Phanerozoic
What supports the oceanic and continental plates of Earth's crust? - ANSWER A
viscous, malleable layer called the mantle
Compared with anaerobic metabolism, aerobic metabolism proceeds _______ rapidly, and
harvests energy _______ efficiently. - ANSWER more; more
Place the periods making up the Paleozoic era in order from oldest to most recent. -
ANSWER Cambrian, Odovician, Silurian, Devonian, Carboniferous, Permian
Recovery from the most extensive continental glaciers since the "snowball Earth" occurred
at the start of the _______ period. - ANSWER Triassic
Which condition was the most likely cause of the limited diversity of multicellular eukaryotes
for much of their early existence? - ANSWER Frequent periods of cold
Which statement about stratigraphy is not true? - ANSWER Similar fossils are
distributed fairly evenly throughout strata of varying ages.
Earth was devoid of life during the _______ eon. - ANSWER Hadean
1
,Three unicellular organisms live in similar low-oxygen environments. Their characteristics are
summarized in the table. Based solely on this information, with all else being equal,
organism _______ should have the greatest oxygen requirement because it has the
_______. - ANSWER Largest volume-to-surface are ratio
During the _______ period continents began to merge, and the first vascular plants and first
terrestrial arthropods emerged on land. - ANSWER Silurian
Radioisotopes are useful in dating fossils and rocks because - ANSWER they decay in a
predictable pattern over long time periods.
Smaller single-celled organisms require lower oxygen concentrations than larger ones do.
This is because the smaller organisms - ANSWER have a greater surface area-to-
volume ratio.
What type of event marked the end of the Ordovician, Devonian, and Permian periods? -
ANSWER Mass extinction
The radiation of reptiles occurred during the Triassic, which gave rise to crocodilians,
_______, and _______. - ANSWER dinosaurs; birds
Which chain of events could have led to a mass extinction event in Earth's past? -
ANSWER Tectonic plate movement → volcanic eruptions → blocked sunlight →
glaciation → drop in sea level
Toward the end of the Permian, oxygen levels _______ due to the _______. -
ANSWER decreased; drying of the lowland swamps
Which phrase best defines the term "climate"? - ANSWER Long-term average
expectations of precipitation and temperatures for a region
2
, When an organism dies, the carbon-14 atoms present in its body - ANSWER stop
exchanging with carbon-14 atoms in the environment.
Which sequence correctly places events in chronological order from earliest to most recent?
- ANSWER End of Ordovician extinction; first vascular plants; insect flight evolves
Which can be dated using carbon-14 dating? - ANSWER A fossil that is between 10,000
and 20,000 years old
What leads scientists to believe that Earth's biota has turned over many times? -
ANSWER Many species last only a few million years, and life has existed on Earth for
billions of years.
Important events in Earth's geological history include
(A) heavy meteorite bombardment
(B) formation of continents Laurasia and Gondwana
(C) accumulation of oxygen in Earth's atmosphere
Which sequence shows these events from oldest to most recent? - ANSWER A, C, B
In a pond, there are 37 species of invertebrates, 18 species of vertebrates, and 73 species of
plants. This pond's fauna includes _______ species. - ANSWER 55
Which particle is produced from a carbon-14 decay event? - ANSWER Nitrogen-14
In one region of undisturbed sedimentary rocks, the Feingold stratum is below the Tucos
stratum and above the Ruff stratum. Based on the principles of stratigraphy, the _______
stratum is oldest, and the _______ is youngest. - ANSWER Ruff; Tucos
3
UPDATE!!!2025/2026|GUARANTEED
The rapid diversification of multicellular organisms occurred in the _______ eon. -
ANSWER Phanerozoic
What supports the oceanic and continental plates of Earth's crust? - ANSWER A
viscous, malleable layer called the mantle
Compared with anaerobic metabolism, aerobic metabolism proceeds _______ rapidly, and
harvests energy _______ efficiently. - ANSWER more; more
Place the periods making up the Paleozoic era in order from oldest to most recent. -
ANSWER Cambrian, Odovician, Silurian, Devonian, Carboniferous, Permian
Recovery from the most extensive continental glaciers since the "snowball Earth" occurred
at the start of the _______ period. - ANSWER Triassic
Which condition was the most likely cause of the limited diversity of multicellular eukaryotes
for much of their early existence? - ANSWER Frequent periods of cold
Which statement about stratigraphy is not true? - ANSWER Similar fossils are
distributed fairly evenly throughout strata of varying ages.
Earth was devoid of life during the _______ eon. - ANSWER Hadean
1
,Three unicellular organisms live in similar low-oxygen environments. Their characteristics are
summarized in the table. Based solely on this information, with all else being equal,
organism _______ should have the greatest oxygen requirement because it has the
_______. - ANSWER Largest volume-to-surface are ratio
During the _______ period continents began to merge, and the first vascular plants and first
terrestrial arthropods emerged on land. - ANSWER Silurian
Radioisotopes are useful in dating fossils and rocks because - ANSWER they decay in a
predictable pattern over long time periods.
Smaller single-celled organisms require lower oxygen concentrations than larger ones do.
This is because the smaller organisms - ANSWER have a greater surface area-to-
volume ratio.
What type of event marked the end of the Ordovician, Devonian, and Permian periods? -
ANSWER Mass extinction
The radiation of reptiles occurred during the Triassic, which gave rise to crocodilians,
_______, and _______. - ANSWER dinosaurs; birds
Which chain of events could have led to a mass extinction event in Earth's past? -
ANSWER Tectonic plate movement → volcanic eruptions → blocked sunlight →
glaciation → drop in sea level
Toward the end of the Permian, oxygen levels _______ due to the _______. -
ANSWER decreased; drying of the lowland swamps
Which phrase best defines the term "climate"? - ANSWER Long-term average
expectations of precipitation and temperatures for a region
2
, When an organism dies, the carbon-14 atoms present in its body - ANSWER stop
exchanging with carbon-14 atoms in the environment.
Which sequence correctly places events in chronological order from earliest to most recent?
- ANSWER End of Ordovician extinction; first vascular plants; insect flight evolves
Which can be dated using carbon-14 dating? - ANSWER A fossil that is between 10,000
and 20,000 years old
What leads scientists to believe that Earth's biota has turned over many times? -
ANSWER Many species last only a few million years, and life has existed on Earth for
billions of years.
Important events in Earth's geological history include
(A) heavy meteorite bombardment
(B) formation of continents Laurasia and Gondwana
(C) accumulation of oxygen in Earth's atmosphere
Which sequence shows these events from oldest to most recent? - ANSWER A, C, B
In a pond, there are 37 species of invertebrates, 18 species of vertebrates, and 73 species of
plants. This pond's fauna includes _______ species. - ANSWER 55
Which particle is produced from a carbon-14 decay event? - ANSWER Nitrogen-14
In one region of undisturbed sedimentary rocks, the Feingold stratum is below the Tucos
stratum and above the Ruff stratum. Based on the principles of stratigraphy, the _______
stratum is oldest, and the _______ is youngest. - ANSWER Ruff; Tucos
3
