Flatworms (apart from the turbellarians, (planarians are in the class turbellaria)) are parasitic and don't need complex nervous systems. A parasitic animal devotes much of itself to reproduction and doesn't worry about other tasks. Cestodes don't even have a gut, they absorb food via diffusion through their skin. Annelids are free-living animals, and they need to move around more. They don't spend their adult life hooked to the inside of an animal, they move around, and need a more complex nervous system to give them a better view of their world.
The correct options are as follows:
1. D.
<span>A clade refers to a group of organisms that are made up of evolutionary descendants that originated from a common ancestor. A clade that will survive a series of catastrophic events must be one that is made up of distantly related and diverse species. This is because, those species will have different type of adaptability capacity and will be able to adapt in different ways to the catastrophic events. Due to the differences in their ability to adapt, some of the specie will survive the catastrophic events even if others are wipe out.
2. B.
The mass extinction of one specie usually creates space for another new specie to survive. The new specie that survive the old one may possess the ability to adapt to the event that wipe out the former set of living organisms and thus, the new specie will be able to occupy and reproduce in their new space. Mass extinction is said to occur when the whole population of living organism living in an ecosystem are wipe out as a result of unfavorable conditions.
3. B.
Convergent evolution refers to the independent evolution of similar features in species that arise from different lineages. The species involved usually evolve these traits as a result of having to adapt to similar environments. Convergent evolution usually result in evolution of analogous structures, that is, structures that have similar forms or functions but which are not present in the last common ancestors of the species.
4. C.
In evolution, gradualism refers to theory that states that evolution occurs slowly and gradually, thus, large changes in evolution are actually product of small changes that occur over a long period of time. The theory of gradualism was originally proposed by James Hutton in 1795.
5. C.
Mass extinction refers to the wiping out of a a large number of species within a very short time. Mass extinction can occur as a result of severe unfavorable conditions that all the species in an ecosystem can not adapt to. An instance of this is a drastic decrease in global temperature after several massive volcanic eruptions.</span>
Ok. so first, the answer is c. then a. then c again. then b. then finally, d. hope this helps!
Answer:
Option (D).
Explanation:
ATP (adenotriphosphate) molecules are considered as energy currency of the cells as molecules provide energy for various cellular functions.
The energy is stored in ATPs in two high-energy phosphate bonds, known as phosphoanhydride bonds. This stored energy is released in during hydrolysis of ATP, which involves removal of terminal phosphate groups bound the carbon backbone.
Thus, the correct answer is option (D).