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Mars2501 [29]
3 years ago
12

The end of the ordovician period was signaled by

Biology
1 answer:
eimsori [14]3 years ago
3 0
According to historical accounts, through the use of advancements in technologies like the carbon dating, it is roughly estimated by scientists that the Ordovician Period lasted only for 45 million years. The end of its era was theorised to had signalled when there was a mass extinction of the marine animals.
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Original strand: GCAATTCGCTATCGTAGG<br>what is the complementary strand​
garri49 [273]

Answer:

CGTTAAGCGATAGCATCC

Explanation:

remember A always pairs with T and G always pairs with C. you can also remember them as Apple Tree and Car Garage.

hope this helps :)

8 0
3 years ago
Explain El Niño, how it’s identified, and it’s potential negative impacts.
nadya68 [22]

I know this is a lot :This might not have negative impacts:

El Niño is a natural phenomenon experienced in the equatorial Pacific which causes temporary alterations in the world climate. It is normally characterized by complex and abnormally warm ocean temperatures in the Pacific Ocean in the area near the equator which results in global weather events and sea-surface temperature changes.

In practical sense, the ocean surface around the equator region warms up by small degrees Celsius along with very heavy thunderstorms. The small rise in temperatures is influenced by change in the normal wind direction. Scientist also prevails that the temperature increases may be intensified by the effects of greenhouse gases and consequent global warming. This small difference in temperature increase has a substantial impact on the world’s climate.

In normal conditions, the wind blow from the east to the west along the equator in the Pacific. These are the trade winds which blow towards the west along the equator. This results in the piling of water in the western side of the Pacific to a sea surface area of up to 18 inches high.

In the eastern side, deeper water (which is cooler compared to the sun-heated warm surface water) gets pulled up from beneath to substitute the water pushed to the west. So, the normal difference in temperature across the equatorial Pacific is cold water (about 22 degrees Celsius) in the east and warm water (about 30 degrees Celsius) in the west.

In El Niño conditions, the winds propelling the water get weaker and as an outcome, some of the warm water collected in the west is heavily drawn towards the east. At the same time, not so much cold water is pulled up from beneath. Accordingly, these elements make the water in the pacific warmer which results in El Niño events.

Drastic Effects of El Niño

Effect on aquatic species and sea birds

In normal situations, the ocean water carry nutrients that lie beneath the ocean to the top thereby allowing the fish species living in the upper waters to feed on the planktons that rely on these nutrients. Seaweeds also rely on cool and nutrient-rich water for survival and growth. An El Niño lessens the upwelling of cold water and the uplift of nutrients from the bottom of the ocean.

As a result, fish either migrate to other regions or die during an El Niño because they lack adequate food for growth and survival. When fish have migrated or reduced in number, other aquatic creatures namely the sea birds and seals that feed on the fish are also affected. Off the coast of California, the aquatic populations such as fish, seals, sea lions, and sea birds are normally affected and deaths are registered during El Niño events.

5 0
3 years ago
What mechanisms are in place in a stream ecosystem to make sure that the populations of biotic elements are controlled and inter
Kipish [7]
In any ecosystem, there are factors to control populations.
In a stream, the predators of a certain organism will help keep populations checked. Moreover, the limited resources, such as space and food, will keep the population from growing out of control.
4 0
3 years ago
Read 2 more answers
Fungi are responsible for what common human ailment? colds the flu athlete's foot infections
Andreas93 [3]
Fungi are responsible for what common human ailment athlete's foot infections
5 0
3 years ago
You observe two populations of chimpanzees using sticks to dig termites out from nests for food. One population uses long sticks
icang [17]

Answer: B. The population using long sticks has mostly long sticks in its environment

Explanation:

Going back to the statement that reiterates the hypothesis after observations about the apes in the Introduction.

Reviewing the findings in this case, on the behavior of using sticks to dig seem to be the focus the experiment and choice length of the stick.

Making a judgment about whether or not the two finding has been supported is next step.

If there are equal numbers of short and long sticks in the environment of each population and the apes chooses one specific we can say their behavior is learned.

 If the chimpanzees using short sticks have made the the sticks short by breaking long sticks then we can say this behavior is learned.

When the Young chimpanzees in both populations start out using sticks of many different sizes we can see that these variables of learning is yet to be perfected.

When individuals in the population that don’t use the common stick length for that population catch fewer termites this reveals a randomness in the behavior of interest.

At this point we can say that if the population using long sticks has mostly long sticks in its environment then there is a biased objective in the study and this does not support the hypothesis that the choice of stick length is a learned behavior.

3 0
3 years ago
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