Let's think of it like this. We have an energy crisis, but how can we solve it? There are three steps. First, we need to recognize that we HAVE a problem that needs to be fixed. Then, we need to determine what's causing the problem. Finally, we need to change how we act in order to solve the problem. Now, let's look at the options.
Is A correct, leaving our behavior unchanged? NO: if we know the cause of the problem, we still need to solve it! What about B: the problems are ignored? NO: you can't solve a problem unless you know it's a problem. C? NO: to solve a problem, you need to find out what's causing it. Finally, let's look at D: behavior is changed after cause is identified. This is correct: not only do we know why it's happening, but we're fixing it!
Answer: D
The correct asnwer to your question - why would a group of antelopes leave the herd for search of a better grassland is an example of emigration - B.
These antelopes would emigrate to a certain grassland and be immigrants in that grassland. This has to be distinguished.
The main reason that most farmers use stem cuttings rather than just planting a seed is that a tree's genetic variation will occur. The seeds of many fruit trees tend to vary differently from the parent, because seeds themselves are produced by sexual reproduction (i.e they receive genes from a male and female to form). As they are a cross from two sets of genes, many fruit trees are not “true to seed”. Their seeds will produce a generally different variety of tree from the parent. When using stem cuttings, it's almost like a cloning process.
Answer:
True, planets are round because of gravity
The correct answer is proteins.
Proteins have four structures; (1) primary, (2) secondary, (3) tertiary, and (4) quaternary. Primary structures of proteins are formation of peptides and the peptide bonds between amino acids. Secondary structures of proteins involves the amino acid composition leading to hydrophobic interactions forming either alpha helices or beta sheets. Interactions between secondary structures of proteins will make the tertiary structure which is either soluble (globular) or insoluble (fibrous) proteins. Quaternary structures are the combination of two or more tertiary structures and these are called subunits.
