Answer & explanation:
The theory of continental drift emerged a long time ago. When mapping some points on Earth, scholars suspected that the continents were united in the past.
Francis Bacon suggested in 1620 that the east coast of the South American continent and the west coast of Africa fit together perfectly, giving the impression that they had parted in the remote past. A similar observation to this had already been made by another scholar named Abraham Ortelius, around 1596.
A century later, hypotheses became a scientific theory with previously elaborated arguments. Then, the theory of Continental Drift was officially born, when the German Alfred Wegener formulated it in 1912, establishing that the Earth had been divided, in its slow fragmentation, into two great continents, Laurasia and Gondwana.
Answer:
Temperatures in a desert climate range from 86 to 104 degrees Fahrenheit, while summers are wet and winters are dry. When the rains fall, herds of prey animals abound as they feed on the lush grasslands and water at the many waterholes and rivers. The average rainfall in the desert is 10 inches per year. Sahara desert vegetation includes African Welwitchsia, date palm, thyme, magaria, olive trees, orange trees, and fig trees. Apart from these, more than half of the Sahara desert is extremely barren with no vegetation found. However, there are still some areas in the Sahara desert that are lush, containing abundant trees and plants. The most common landscape features found in deserts are sand dunes, yardangs, desert pavements, debris, playas, oases, mesas, alluvial fans, arroyos and buttes. These landforms vary from desert to desert. In areas dominated by the tundra climate type, winters are long and cold, especially in the region north of the Artic Circle where, for at least one day in the year, the Sun does not rise. Winter precipitation generally consists of dry snow, with seasonal totals less than in the summer when cyclonic storms that develop along the boundary between the open ocean and sea ice yield rainfall. The average snowfall in the tundra is 10-40 inches per year. Tundra vegetation is composed of dwarf shrubs, sedges and grasses, mosses, and lichens. Scattered trees grow in some tundra regions. The ecotone between the tundra and the forest is known as the tree line or timberline. The arctic tundras located between the north pole and the coniferous forests or taigaregion. It is characterized by extremely cold temperatures and land that remains frozen year-round. Arctic tundra occurs in frigid mountaintop regions at very high elevations.
decreased ability to survive changing conditions
Hope this helps
Answer:
Three molecules
Explanation:
Since fats consist of three fatty acids and a glycerol, they are also called triacyclglycerols or triglycerides. Triacyclglycerols: Triacylglycerol is formed by the joining of three fatty acids to a glycerol backbone in a dehydration reaction. Three molecules of water are released in the process.
Trisomy=3 chromosomes; 1 more than the required pair (2)
21=the type of chromosome
So, here we can eliminate A and B.
Now we have C and D.
I know that when sperm cell(s) simultaneously fertilize [an] egg, a class of identical twins will form. Therefore, we can eliminate D, leaving us with merely C. Henceforth, C is your final answer.