Answer:
Answer : Depolarized
Explanation:
Sodium and Potassium ions tend to move inside of the axin when the membrane is depolarized.
A change in polarity occurs in the axon membrane when a nerve impulse travels across it. At the beginning of an action potential or nerve impulse , the ions of sodium tend to move inside of axon causing depolarization. As a result potassium ions tend to move outside of the axon causing re polarization. Hence, this effect causes the nerve impulse to travel in one direction only inside the axon.
Answer:
variation
Explanation:
Genetic variation is what makes us all unique as a result of subtle changes in our DNA. The Theory of Evolution is a process in which organisms change over time as a result of adapting to their environment. Charles Darwin came up with the term Survival of the fittest, in any environment plants and animals from the same species show natural variation in their physical characteristics, like neck lengths in giraffes. Darwin suggested that the plants and animals best suited to the environment will survive and pass on their characteristics to their offspring. Over time, the characteristics of the surviving members of the species will become predominant.
Example: Peppered moth
In London in the 1800's, 98% of peppered moths had light colored bodies and only 2% were dark. The light moths were the same color as the trees so they could easily hide from hungry birds and not get eaten. The dark moths however were easy to see and were eaten. Then came the factories and smoke of the industrial evolution and many trees turned black with soot and suddenly the dark moths were able to survive better as they now looked like the trees and the light colored moths were easier to spot and eat. By 1895 the dark peppered moths made up 95% of the population and the light colored moths only 5%. This is an example of natural selection, because of the gene that makes the moths dark, it allowed them to flourish when the environment changed, they adapted, reproduced and survived.
Genetics is a branch of biology concerned with the study of genes, genetic variation, and heredity in living organisms.[1][2][3]
The discoverer of genetics is Gregor Mendel, a late 19th-century scientist and Augustinian friar. Mendel studied "trait inheritance", patterns in the way traits are handed down from parents to offspring. He observed that organisms (pea plants) inherit traits by way of discrete "units of inheritance". This term, still used today, is a somewhat ambiguous definition of what is referred to as a gene.
Trait inheritance and molecular inheritance mechanisms of genes are still primary principles of genetics in the 21st century, but modern genetics has expanded beyond inheritance to studying the function and behavior of genes. Gene structure and function, variation, and distribution are studied within the context of the cell, the organism (e.g. dominance), and within the context of a population. Genetics has given rise to a number of subfields, including epigenetics and population genetics. Organisms studied within the broad field span the domains of life (archaea, bacteria, and eukarya).
Genetic processes work in combination with an organism's environment and experiences to influence development and behavior, often referred to as nature versus nurture. The intracellular or extracellular environment of a cell or organism may switch gene transcription on or off. A classic example is two seeds of genetically identical corn, one placed in a temperate climate and one in an arid climate. While the average height of the two corn stalks may be genetically determined to be equal, the one in the arid climate only grows to half the height of the one in the temperate climate due to lack of water and nutrients in its environment.
