Answer:
The answer is the halo stars and globular clusters are distributed in a roughly shperical region surrounding and centered on the disk, the sun is loacted roughly halfway out from the center in the plane of the disk.
Explanation:
The statement that best describes is the halo stars and globular clusters are distributed in a roughly shperical region surrounding and centered on the disk, the sun is loacted roughly halfway out from the center in the plane of the disk.
Answer:
7) The Cretaceous period and it lasted for 80 million years
8) The Cenozoic era for 65 million years
9) 4.5 billion years ago
10) It began 252.2 million years ago
11) It ended 66 million years ago
12) About 190 million years
Explanation:
Hope this helps :)
Answer:
D it causes river channels to change shape
Answer:
There are several tectonic provinces collectively called as crystalline providences.
Explanation:
- The geology of Appalachians consists of Blue Ridge, Piedmont, Adirondack, and the New England providences. They are known as Crystalline provinces.
- The sinking of the oceans continued about 270 million year ago due to which a huge mass of rocks was pushed westwards along the margins of North America and piled up to form the mountains.
- The Sierra Nevada is the youngest mountain range on the west coast of the United States.
Explanation:
- Microscopes: Anton van Leeuwenhoek is considered the precursor of cellular and experimental biology as well as microbiology, in 1674, he used a homemade microscope to become the first person to discover microbes, he described seeing animalcules in a drop of water, he also discovered red blood cells and bacteria in 1676.
- Pasteurization: it's a process in which water and certain foods like milk and juice, are treated with mild heat, usually before boiling point, to eliminate pathogens. It was named after Louis Paster, who in the 1860s demonstrated that heating beverages to about 57°C for a few minutes could prevent abnormal fermentation, this treatment also destroys microorganisms that cause spoilage and so it prolongs the storage time of food.
- Koch postulate: In 1890, Robert Koch set out his criteria for judging whether a bacteria is the cause of a disease. These postulates are: The bacteria must be present in every case of the disease, it must be isolated from the host and grow in culture, the disease is reproduced when a bacteria from the pure culture is inoculated into a healthy host, the bacteria must be recoverable from the infected host. These postulates are useful to find the cause-effect relationship between bacteria and clinical disease.
- Antibiotics: In 1928, Alexander Fleming, discovered mold as an antibacterial agent after this one contaminated his<em> Staphylococcus aureus </em>dishes, inhibiting it's growing, this mold was then named penicillin and it was the beginning of a transformation in human health.
- Vaccines: the first successful vaccine development was introduced in 1796 by Edward Jenner, this advance was achieved after he followed up his observation of milkmaid who previously caught cowpox did not later catch smallpox by showing that inoculated cowpox protected against inoculated smallpox.
I hope you find this information useful and interesting! Good luck!
