ece test #1

Question 1

Biodiversity (5)

Answer 1

The variety of life in an area (plants, animals, microbes).

Human actions like pollution, deforestation, and climate change reduce biodiversity.

Question 2

Food Production (5)

Answer 2

Our ability to grow and harvest food.

Affected by things like soil health, climate, and water access.

Question 3

Average Global Temperature (5)

Answer 3

Earth’s temperature is rising due to greenhouse gases from burning fossil fuels (like CO₂).

Causes melting ice, sea level rise, and extreme weather.

Question 4

Human Population (5)

Answer 4

The number of people on Earth keeps growing.

More people = more resource use and more pollution.

Question 5

Resource Depletion (5)

Answer 5

Using up natural resources faster than they can be replaced (e.g., water, soil, fossil fuels, forests).

Question 6

Law of Superposition:

Answer 6

In layers of rock/soil, the oldest layers are at the bottom and newer ones are at the top (used for relative dating).

Question 7

Radioactive Dating:

Answer 7

A method of determining the exact age of an object by measuring radioactive isotopes (used for absolute dating).

Question 8

Half-Life:

Answer 8

The time it takes for half of a radioactive isotope to decay.

Question 9

Decay:

Answer 9

When a radioactive atom breaks down over time into a different, more stable element.

Question 10

Isotope:

Answer 10

Versions of an element that have the same number of protons, but different neutrons.

Question 11

Proton:

Answer 11

A positively charged particle in the nucleus of an atom.

Question 12

Neutron:

Answer 12

A neutral particle in the nucleus (no charge).

Question 13

Electron:

Answer 13

A negatively charged particle that orbits the nucleus.

Question 14

Radioactive:

Answer 14

An unstable isotope that releases energy/particles (decays).

Question 15

Nucleus:

Answer 15

The center of the atom where protons and neutrons are located.

Question 16

Law of Superposition:

Answer 16

deeper = older.

Question 17

Isotopes of the same element have:

Answer 17

Same number of protons

Different number of neutrons

This changes their mass and sometimes makes them radioactive.

Question 18

Using the periodic table to find protons and neutrons

Answer 18

Atomic number = # of protons

Mass number (rounded) − atomic number = # of neutrons

Question 19

The main isotopes of carbon

Answer 19

Carbon-12 (most common, stable)

Carbon-13 (stable, rare)

Carbon-14 (radioactive, used in dating things that were once alive)

Question 20

How radioactive carbon forms and decays

Answer 20

Carbon-14 forms in the atmosphere → plants absorb it → animals eat plants.

After death, Carbon-14 decays over time → scientists measure how much is left to determine age.

Question 21

How radiocarbon dating works

Answer 21

Living things have a constant amount of Carbon-14

After death, no new Carbon-14 is taken in

Scientists measure how much Carbon-14 remains and use its half-life (5,730 years) to calculate age.

Question 22

Using a graph of radioactive decay

Answer 22

The graph shows how much of the isotope is left over time.

You can calculate the age of a sample by matching how much isotope is left to how many half-lives have passed.

Question 23

How Easter Island’s environment and population changed

Answer 23

Originally had forests and a stable population.

Overused resources (cut trees, overfarmed), which caused:

Soil erosion

Loss of food

Collapse of civilization

Question 24

Explain how Easter Islanders lived

Answer 24

Built huge stone statues (Moai), farmed, fished, and had a complex society.

Likely had strong spiritual beliefs tied to the statues.

Question 25

Explain why Easter Island is a warning for us

Answer 25

It’s an example of what happens when a society uses up its resources without planning for the future. Teaches us the importance of sustainability.