Answer:
Evolution is driven by rare mutations that occur in the DNA of organisms. These mutations could be lethal, neutral and some advantageous. The lethal mutations cannot exist in a population because the offspring is unable to survive to term in pregnancy or dies just after birth. The neutral are ones that do not considerably affect the organisms – though they could result in a disadvantage. The beneficial ones are the one that is kept in the population by natural selection because they confer an advantage e.g in the fight for resources or escaping predation and etcetera. Therefore, it's like a game of chances by nature. Paleontologists discover many species of organisms some of which are imperfect because nature produced them but they died off because their mutations gave them a disadvantage against better-adapted individuals.
The <em>Tiktaalik</em> fish from 375 million years ago became extinct because it did not well-developed eardrum for detecting vibrations in water which is significant in survival.
Dinosaurs during development of feathers had many imperfect species before the right wings for flight were conjured up by nature. An imperfect species is the <u><em>Tianyulong confucius</em></u> had stiff feathers that lacked vanes hence were not ideal for flight
The answer is true, they are only single celled!
Answer:
C. Liquid molecules and atoms are able to slip around each other and fill in gaps between them.
Explanation:
The liquid is a state of matter that has no definite shape. In fact, it can adapt to the shape of its container. This is because of the reason that molecules in the liquid phase have high kinetic energy and weak binding forces. The high energy keeps them moving freely and thus can take the shape of it its container. On the other hand, in solids, the binding forces are stronger and molecules have very little energy to move freely.
Example: If we melt a solid, the molecules initially have less energy. However, when we heat them, they gain energy and start moving. Upon further heating, they will have enough energy to break the bondings and move around. This is why the solid structure will change to the liquid.