Twenty

In 1859, Charles Darwin proposed a theory based on the concept of natural selection. His theory explains the evidence of the gradual changes of all organisms over millions of years. This theory is known as the Theory of __________________.

• Mutation

• Adaptations

• Natural Selection

• Evolution

Tags

NGSS.MS-LS4-2

NGSS.MS-LS4-4

Why is relative dating useful? What does it tell scientists?

• It tells scientists the exact, precise age of specimens.

• It tells scientists the approximate age of specimens, compared to other known examples.

• Scientists rarely use relative dating.

• Relative dating is the best way to learn about Earth's history.

Which would most likely happen if too many nutrients entered an estuary?

• Nutrients would be used up by the fish and plants, keeping the estuary in balance.

• Algal blooms would lower dissolved oxygen levels, causing fish to suffocate.

• Algal blooms would decrease, leaving few food resources for fish.

• Nutrients would sink to the bottom, increasing soil deposition.

Tags

NGSS.MS-LS2-1

NGSS.MS-LS2-3

NGSS.MS-LS2-4

An increase in the amount of nutrients in a lake is known as

• calcification

• cellular respiration

• eutrophication

• photosynthesis

Tags

NGSS.MS-LS2-1

NGSS.MS-LS2-4

What can be a source of nitrates for eutrophication in rivers?

• fertilisers

• plastic bottles

• paper

• sewage

Based on the diagram, which fish species is in a breeding zone with higher oxygen levels?

• Fish Species 1

• Fish Species 2

Tags

NGSS.MS-LS2-1

Why should farmers be concerned about unused nitrate fertilizer contaminating surface water and groundwater supplies?

• Unused nitrates reduce algae growth.

• Unused nitrates increase oxygen in the water.

• Excessive amounts of nutrients cause overpopulation of fish.

• Excessive amounts of nutrients speed up the eutrophication process.

Tags

NGSS.MS-LS2-4

NGSS.MS-LS2-5

Where is the most likely location of a dead zone in this watershed?

• A

• B

• C

• I

• H

Tags

NGSS.MS-ESS3-4

NGSS.MS-LS2-1

NGSS.MS-LS2-4

What is the very next thing that happens after fertilisers enter a river in eutrophication?

• Fish die due to a lack of oxygen

• Plants below the surface die due to a lack of sunlight

• The number of aerobic bacteria increases

• Fast growth of plants

Tags

NGSS.MS-LS2-1

What is the atomic number of Calcium?

• 18

• 20

• 22

• 24