Answer:
B. Some countries have many sources of beryllium, and some have no sources of beryllium.
Explanation:
Beryllium is a very important mineral that is present in many countries. All countries did not have beryllium deposits. Some countries have many sources and deposits of beryllium, and some have no sources of beryllium. There are many deposits of beryllium in different parts of United states of America. Those countries which have no beryllium deposits have cell phones because they purchase cell phones from international market by paying money which can be earned through selling of its goods.
Answer:
D two organisms depend on each other for survival.
Explanation:
Symbiotic relationship is a type of relationship between two organisms in which the both of them gain something positive from each other. A good example is the relationship between the cattle and egret. The egret helps in grooming the cattle and the cattle in return provides food for the egret.
In a symbiotic relationship, two organisms depend on each other for survival and is the right choice in the above question.
Catenation:
The property of self linkage among identical atoms to form long chain compounds is known as catenation. Carbon exhibits maximum catenation, when compared to elements like sulphur and silicon, due to strong carbon-carbon bonds and tetra valency. Due to this catenation, carbon atoms can form various types of straight chains, branched chains and ring structures.
Formation of multiple bonds:
Carbon atoms are capable of forming multiple bonds with other carbon atoms.
Hydrocarbons:
All the carbon compounds which contain just carbon and hydrogen are called hydrocarbons.
isomerism arises from the difference in the structure of carbon chain which forms the nucleus of the molecule. It is, therefore, named as chain, nuclear isomerism or Skeletal isomerism. For example, there are known three pentanes which have the same molecular formula.
Answer: This is True
Explanation: DNA is copied and carried down into generations every time an organism sexually reproduces.
Pasteurized milk doesn't contain these beneficial bacteria, although some good bacteria can be regained by culturing the milk into such foods as yogurt or kefir.
