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
Red and yellow bell pepper plant can reproduce with each other - Genetic diversity.
A park has 80 species of trees - species diversity.
There are many breeds of dogs - genetic diversity.
Five different bird species are at a bird feeder - species diversity.
Answer:
e. unique three-dimensional shape of the fully folded polypeptide.
Explanation:
The tertiary structure of a protein is the unique three-dimensional structure which emanates from the interaction between the “R groups” of the several amino acids that make up the polypeptide. Hydrogen bonding is one of the interactions that occur that gives the protein this structure. Other interactions are ionic bonding, dipole-dipole interactions, hydrophobic interactions, among others. The function of a protein is dependent on its tertiary structure, as a disruption of the tertiary structure causes a protein to be denatured, thereby rendering the protein not functional.
