Ecosystems
Name 3 types of symbiotic relationships
What do we call the trace remains of an organism that lived long ago?
A fossil
What is the basic building block of all matter?
An atom
What percentage of Earth's water is salt water found in oceans?
About 97%
How old is the Earth estimated to be?
Around 4.5 - 4.6 billion years
What happens to most of the energy as it moves throughout a food web?
It is changed into HEAT energy
What process drives evolution, often called "survival of the fittest"?
Natural selection
Where are protons and neutrons located in an atom?
Inside the nucleus
Where is most of Earth's freshwater frozen and stored?
Glaciers and ice caps
Which law states that older rock layers are usually at the bottom?
the Law of Superposition
What do we call an organism that makes its own food using sunlight?
An autotroph
What is a trait that helps an organism survive in its environment?
An adaptation
Is tearing a piece of paper a physical change or a chemical change?
Physical change
What do we call an underground layer of rock or sediment that holds water?
An aquifier
What was the name of the ancient supercontinent where all landmasses were joined?
Pangea
What term describes the maximum population size that an ecosystem can support?
Carrying capacity
What do we call a leftover body part that has lost its original use, like a whale's hip bone?
What is a substance made of two or more different elements that are chemically combined?
A compound
What do we call the area of land where all the water drains into the same river or ocean?
A watershed
What do scientists use to split Earth's long history into chunks of time based on major events?
Geologic time scale
What is the process where a disturbed ecosystem slowly regrows and changes over time?
Ecological succession
What type of evolution happens when unrelated species develop similar traits because they live in similar environments?
Convergent evolution
What type of chemical reaction absorbs heat and makes the surroundings feel colder?
An endothermic reaction
What process happens when too many nutrients in water cause algae blooms that use up all the oxygen?
Eutrophication
What is an underground body of rock formed when magma cools and hardens before reaching the surface?
An intrusion