Boiling water is a physical change. This is because the water that is being changed into a gas, and can be changed back. Bohr proposed a theory that helped make the blueprint for the atomic model. Gold is a soft but heavy metal, and reflects light with a green/blue hue. Gold is a shiny yellow to canary yellow in colour, and is often confused with pyrite, or 'fool's gold'. The particles in a solid vibrate in place, and are very close together. When one atom of carbon and two of oxygen meet, the make a bond that in turn creates CO2 or carbon dioxide. I hope I helped. :)
The satellite that orbit earth without gravity would collide into earth since there is no gravity to hold it up there in space.
Answer:
A pandemic is an epidemic disease extended across wide regions, thereby affecting many countries and even continents, while endemic diseases affect the people from only one country or a specific region. Human Immune Deficiency (HIV) is an RNA virus whose life cycle is composed of the following stages: 1) binding to the cell host and membrane fusion, 2) subsequent reverse transcription into DNA and integration into genome host 3) proliferation (i.e., successive replication cycles) by using the cellular machinery of the host 4) new assembly and budding of the virus. The acquired immune deficiency syndrome (HIV/AIDS) occurs when the host immune system is seriously damaged by the HIV infection, this being the latest stage of infection. It is known that HIV/AIDS is more prevalent in the female population, while according to ethnic groups, it is more prevalent in African-American and Hispanic/Latino populations in the USA. The life expectancy in HIV-infected patients has notably improved in the last years and, currently, people with this disease can expect to live over 70 years or even more.
DNA ligases close nicks in the phosphodiester backbone of DNA. Biologically, DNA ligases are essential for the joining of Okazaki fragments during replication, and for completing short-patch DNAsynthesis occurring in DNA repair process. There are two classes of DNA ligases.