The Hertzsprung-Russell diagram is one of the most important tools in the study of stellar evolution. Developed independently in the early 1900's by Ejnar Hertzsprung and Henry Norris Russell, it plots the temperature of stars against their luminosity (the theoretical HR diagram), or the color of stars against their absolute magnitude
Depending on its initial mass, every star goes through specific evolutionary stages dictated by its internal structure and how it produces energy. Each of these stages corresponds to a change in the temperature and luminosity of the star, which can be seen to move to different regions on the HR diagram as it evolves. This reveals the true power of the HR diagram – astronomers can know a star’s internal structure and evolutionary stage simply by determining its position in the diagram.
The Hertzsprung-Russell diagram the various stages of stellar evolution. By far the most prominent feature is the main sequence (grey), which runs from the upper left (hot, luminous stars) to the bottom right (cool, faint stars) of the diagram. The giant branch and supergiant stars lie above the main sequence, and white dwarfs are found below it.
Answer: I believe that the answer is D.
Explanation:
Answer: a) true
Explanation:
The goal of mitosis is to produce daughter cells that are genetically identical to the mother cell, without a single extra or missing chromosome. Meiosis, on the other hand, is only used for one purpose in the human body: the production of gametes or sex cells, i.e. sperm and eggs. The question is oriented to mitosis, <u>in which prior to this cell division, the cell duplicates its DNA</u> so that each daughter cell then inherits the genetic material. That is, the cell originally possesses 23 chromosomes, they duplicate to a total of 46 so that then each daughter cell receives 23.
The metaphase is the second phase of mitosis and meiosis that occurs after prophase where the envelope is lost and microtubules of the achromatic spindle (also called meiotic or mitotic) appear.
During metaphase, the chromosomes align themselves in the middle of the cell and this balanced midline spindle alignment is due to the equal and opposing forces generated by the kinetochore brothers.
Then during metaphase, the chromosomes will line up in the center of the cell to be separated and go each to a different daughter cell. But the moment they're found there, each orientation of chromosomes produces gametes with the same genetic information from each parent. <u>Because because there have been no changes or mutations in the chromosomes, they have duplicated and have the same genetic information.</u>
Golden retrievers: loyal and playful family dogs
Pit bulls: bred for property guards and sadly dog fighting
German Shepard(K-9): good strength, sense of smell, speed, and stamina. Commonly used in the police force.
