Answer: More than 99 percent of all organisms that have ever lived on Earth are extinct. As new species evolve to fit ever changing ecological niches, older species fade away. But the rate of extinction is far from constant. At least a handful of times in the last 500 million years, 75 to more than 90 percent of all species on Earth have disappeared in a geological blink of an eye in catastrophes we call mass extinctions.
Though mass extinctions are deadly events, they open up the planet for new forms of life to emerge. The most studied mass extinction, which marked the boundary between the Cretaceous and Paleogene periods about 66 million years ago, killed off the nonavian dinosaurs and made room for mammals and birds to rapidly diversify
Answer:
The correct answer is D. is a facultative anaerobe
Explanation:
A facultative anaerobe is the organisms that can live in the absence of oxygen but prefer to utilize the oxygen when oxygen is present in the environment.
An anaerobic organism requires more amount of energy sources like carbohydrates because they use the fermentation process to make energy and this process results in the formation of less energy than aerobic respiration.
All the bacteria of family Enterobacteriaceae that live in the intestine are facultative anaerobes. Therefore facultative anaerobe can thrive in both the presence and absence of oxygen so the correct answer is D. is a facultative anaerobe.
I believe that it's called an adaptation.
Hope I helped you
Answer:
the time that cell spend in prophase is 30 minutes
Explanation:
The computation is shown below:
= Number of cell ÷ sample
= 25 ÷ 100
= 1 ÷ 4
Now it takes two hours
So,
= 1 ÷ 4 × 2 hours
= 0.5
This 0.5 represent the 30 minutes
Hence, the time that cell spend in prophase is 30 minutes
