unit 10 geologic time review

during which geologic period did the earliest birds exist?

• jurassic

• cretaceous

• devonian

• cambrian

Tags

NGSS.MS-LS4-1

during which period did the earliest trilobites exist?

• silurian

• cambrian

• neogene

• carboniferous

Tags

NGSS.MS-ESS1-4

what percentage of time have humans existed on earth?

• 90%

• 20%

• 1%

• 15%

how does the percentage of a parent isotope change after each half-life?

• it decreases by 100% each time

• the percentage does change

• it decreases by half each time

• it decreases by 25% each time

Tags

NGSS.HS-PS1-8

radioactive dating of rocks is helpful for determining the age of rocks because...

• radioactive isotopes are easily detectable

• they are found in all rocks

• radioactive isotopes decay at a predictable rate

• they decay into living things

Tags

NGSS.HS-PS1-8

which group of organisms has NOT existed since the Cambrian period?

• brachiopods

• gastropods

• corals

• placoderm fish

Tags

NGSS.MS-LS4-1

which group of organisms lived for the shortest period of time, according to the fossil record?

• placoderm fish

• birds

• dinosaurs

• trilobites

Tags

NGSS.MS-LS4-1

what do scientists believed caused the extinction of the dinosaurs?

• a tsunami

• meteorite impact

• disease

• ice age

Tags

NGSS.MS-LS4-1

during which epoch was there the existence of diverse bony fish?

• early cretaceous

• late permian

• early silurian

• middle devonian

Tags

NGSS.MS-LS4-1

a half life tells us...

• how long it takes all of a parent isotope to turn to a daughter isotope

• how long it takes a quarter of a parent isotope to turn to a daughter isotope

• how long it takes half a parent isotope to turn to a daughter isotope

• how long it takes half a daughter isotope to turn to a parent isotope

Tags

NGSS.HS-PS1-8