In a small bay that contains a coral reef, the water temperature has remained the same for decades. Recently, scientists discovered that the water temperature in the bay has increased by 1°C. Which is most likely to happen?(1 point)

Question

Responses

The coral in the reef will gain more zooxanthellae.
The coral in the reef will gain more zooxanthellae.

The coral reef will experience a bleaching event.
The coral reef will experience a bleaching event.

The corals in the reef will immediately die.
The corals in the reef will immediately die.

The coral reef will undergo a period of intense growth.

Answer 1

The most likely outcome is:

The coral reef will experience a bleaching event.

Coral bleaching typically occurs when water temperatures rise, leading to stress in coral organisms. This causes them to expel the zooxanthellae, the symbiotic algae that provide the corals with nutrients and their color, leading to a bleaching effect. While other outcomes are possible, the immediate response to a rise in water temperature is often bleaching.

Answer 2

What is an example of a physical weathering?(1 point)
Responses

a rock wearing down due to acid rain
a rock wearing down due to acid rain

microscopic organisms producing compounds that break down rock
microscopic organisms producing compounds that break down rock

bits being blown off a rock by heavy winds
bits being blown off a rock by heavy winds

a metal tool left outside beginning to rust

Answer 3

An example of physical weathering is:

bits being blown off a rock by heavy winds.

Physical weathering involves the mechanical breakdown of rocks without changing their chemical composition, and this option fits that definition well.

Answer 4

What evidence is there that oxygen levels in the sea increased due to photosynthetic bacteria?(1 point)
Responses

decreases in anaerobic organisms
decreases in anaerobic organisms

rust deposits in today’s ocean
rust deposits in today’s ocean

global cooling
global cooling

rust deposits in the ancient ocean

Answer 5

The evidence that oxygen levels in the sea increased due to photosynthetic bacteria is:

rust deposits in the ancient ocean.

The appearance of iron oxide (rust) in geological records suggests that there were higher levels of oxygen in the oceans, which reacted with soluble iron to form insoluble iron oxides. This is often associated with the Great Oxidation Event, when photosynthetic organisms began releasing significant amounts of oxygen into the atmosphere and oceans.

Answer 6

Why do scientists know very little about life in the Precambrian eon?(1 point)
Responses

All of these forms of life are now extinct.
All of these forms of life are now extinct.

There was no life on Earth during that eon.
There was no life on Earth during that eon.

There are few fossils from that time.
There are few fossils from that time.

The eon started with a mass extinction.

Answer 7

Scientists know very little about life in the Precambrian eon primarily because:

There are few fossils from that time.

The Precambrian eon encompasses roughly 88% of Earth's history, and fossil evidence from this time is scarce, making it difficult to study the life forms that existed. While some life did exist and some forms are now extinct, the lack of fossil record is the key reason for the limited understanding of life during this eon.

Answer 8

Which describes the physical weathering of rock by water?(1 point)
Responses

Water carries away pieces of rock.
Water carries away pieces of rock.

Water breaks down a rock into smaller pieces with the same composition as the larger rock.
Water breaks down a rock into smaller pieces with the same composition as the larger rock.

Water dissolves rock into a solution.
Water dissolves rock into a solution.

Any break down of a rock is the same as physical weathering of rock by water.
Any break down of a rock is the same as physical weathering of rock by water.

Answer 9

The statement that best describes the physical weathering of rock by water is:

Water breaks down a rock into smaller pieces with the same composition as the larger rock.

This process, known as mechanical weathering, involves the physical breakdown of rocks into smaller fragments without altering their chemical composition. The other options either involve chemical weathering (like dissolving) or are not accurate descriptions of physical weathering.

Answer 10

What is true about the age of Earth? (1 point)
Responses

Earth formed soon after the Big Bang.
Earth formed soon after the Big Bang.

Earth formed around the same time as other planets in the galaxy.
Earth formed around the same time as other planets in the galaxy.

The sun formed and then a few billion years afterward, Earth formed.
The sun formed and then a few billion years afterward, Earth formed.

Earth formed around the same time as meteorites in the solar system.

Answer 11

The statement that is true about the age of Earth is:

Earth formed around the same time as meteorites in the solar system.

Earth and the other planets in our solar system formed from the protoplanetary disk of gas and dust surrounding the early Sun, leading to their formation approximately 4.5 billion years ago, around the same time as meteorites, which are among the oldest objects we can study to understand the early solar system.