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
Answer:
b. x chromosome inactivation
Explanation:
As you know, female cats have an x chromosome inherited from their mother and an x chromosome inherited from their father. After these two chromosomes are inherited and determine the sex of the cat, one of them will be disabled at some point in fetal development. Inside the X chromosome is the gene that determines the coat color of cats, when one of the two x chromosomes is deactivated, the other x chromosome will have all of its cells activated. In this case, if the activated chromosome is the one that has genes for the "cheetah" pattern of the coat color, all the descendants of this female cat also have the same coat.
The 2nd goes to first 1st goes to second 3rd goes last 5th goes 3rd
C
Neurons and other components come together to form nerve tissue
The brain is formed of many different parts and types of tissues
The central nervous system runs through the body and consists of many parts
A human being has many different systems
How many chromosomes would be present in a cell after anaphase of Mitosis?
During anaphase, sister chromatids separate to opposite sides of the cell. Therefore the 4n after doubling returns to 2n at each end of the dividing cell after anaphase. But until cytokinesis (1 cell pinching into 2), it's still one cell therefore 4n = 28
