Answer:
Until recently, most neuroscientists thought we were born with all the neurons we were ever going to have. As children we might produce some new neurons to help build the pathways - called neural circuits - that act as information highways between different areas of the brain. But scientists believed that once a neural circuit was in place, adding any new neurons would disrupt the flow of information and disable the brain’s communication system.
In 1962, scientist Joseph Altman challenged this belief when he saw evidence of neurogenesis (the birth of neurons) in a region of the adult rat brain called the hippocampus. He later reported that newborn neurons migrated from their birthplace in the hippocampus to other parts of the brain. In 1979, another scientist, Michael Kaplan, confirmed Altman’s findings in the rat brain, and in 1983 he found neural precursor cells in the forebrain of an adult monkey.
These discoveries about neurogenesis in the adult brain were surprising to other researchers who didn’t think they could be true in humans. But in the early 1980s, a scientist trying to understand how birds learn to sing suggested that neuroscientists look again at neurogenesis in the adult brain and begin to see how it might make sense. In a series of experiments, Fernando Nottebohm and his research team showed that the numbers of neurons in the forebrains of male canaries dramatically increased during the mating season. This was the same time in which the birds had to learn new songs to attract females.
Why did these bird brains add neurons at such a critical time in learning? Nottebohm believed it was because fresh neurons helped store new song patterns within the neural circuits of the forebrain, the area of the brain that controls complex behaviors. These new neurons made learning possible. If birds made new neurons to help them remember and learn, Nottebohm thought the brains of mammals might too.
Other scientists believed these findings could not apply to mammals, but Elizabeth Gould later found evidence of newborn neurons in a distinct area of the brain in monkeys, and Fred Gage and Peter Eriksson showed that the adult human brain produced new neurons in a similar area.
For some neuroscientists, neurogenesis in the adult brain is still an unproven theory. But others think the evidence offers intriguing possibilities about the role of adult-generated neurons in learning and memory.
if wrong report me
Answer:
I believe it is receptors
Answer:
The correct answer will be option - D.
Explanation:
Slime moulds are the fungus-like protists which bear a structure called sporangium which produces spores. The sporangium is produced in fungi as well due to which these protists are called fungus-like. Although both produce sporangium but they are not closely related, rather they are distantly related organisms.
The appearance of a sporangium in both indicates that they had faced the same conditions due to which they both showed the same adaptation by producing the same structures performing the same function. In evolutionary terms, this is an example of convergent evolution.
Thus, option D is the correct answer.
Answer:
The human body uses just 21 amino acids to make all the proteins it needs to function and grow. Because amino acids can be arranged in many different combinations, it's possible for your body to make thousands of different kinds of proteins from just the same 21 amino acids.
<span>The correct format for an MLA in-text citation for an article with no known author is A. ("Title" page). The "Title" is the shortened title of the work. It is in lieu of the author's name. The quotation mark that encloses the title is used when the work is a short work like an article. If the work is a long one like books, plays, etc. The title is italicized instead of enclosed in quotation marks.</span>
