During late adulthood, the risk of developing diseases such as cardiovascular diseases and cancer continues to rise. Most people also have a decline in strength and stamina. Their senses may start failing, and their reflex time typically increases. Their immune system also doesn't work as well as it used to. As a result, common diseases like the flu may become more serious and even lead to death. The majority of late adults develop arthritis, and as many as one in four develop Alzheimer's disease. Two brothers were born 20 years apart. Tom, the older brother, was 72, while Dan was 52 years-old. they got along pretty well. Which brother had a greater chance of developing cardiovascular diseases?
Ans: Tom

Once again, a mutation is the change in the DNA or RNA sequence. In multicellular organisms, mutations can be subdivided into germline mutations and somatic mutations. Germline mutations occur in the DNA of sex cells, or gametes, and are therefore potentially very serious. These mutations can be passed to the next generation. If the zygote contains the mutation, every cell in the resulting organism will have that mutation. If the mutation results in a disease phenotype, the mutation causes what is called a hereditary disease. Somatic mutations , which occur in somatic, or body, cells, cannot be passed to the next generation (offspring). Mutations present in a somatic cell of an organism will be present (by DNA replication and mitosis) in all descendants of that cell. If the mutation is present in a gene that is not used in that cell type, the mutation may have no effect. On the other hand, the mutation may lead to a serious medical condition such as cancer. The specialists studied two groups of larvae. Group L displayed all kinds of mutations while group D didn't. Which group of larvae had fewer somatic mutations?
Ans: group D

A firm with high fixed costs requires a large number of customers in order to have a meaningful return on investment. This is where economies of scale become important. Since each firm has large initial costs, as the firm gains market share and increases its output the fixed cost (what they initially invested) is divided among a larger number of customers. Therefore, in industries with large initial investment requirements, average total cost declines as output increases over a much larger range of output levels. City D's mayor wants to invite more businesses in the city. Three firms, firm A, firm B, and firm C, took advantage of this opportunity. Firm A does not require large initial costs, but firm B and firm C require large initial costs. Firm B managed to increase its market share, but firm C failed to increase its market share. Would firm B most likely fail or succeed in achieving a meaningful return on investment if they don't get a large number of customers?
Ans: fail

While the Grants were on the Galapagos, a drought occurred. As a result, fewer seeds were available for finches to eat. Birds with smaller beaks could crack open and eat only the smaller seeds. Birds with bigger beaks could crack and eat seeds of all sizes. As a result, many of the small-beaked birds died in the drought. Birds with bigger beaks survived and reproduced (see Figure below ). Within 2 years, the average beak size in the finch population increased. Evolution by natural selection had occurred. The explorers visited Galapagos 1 and Galapagos 2, both islands part of the same archipelago. Island 1 had experienced a drought in recent years. Both islands had populations of birds living there. Which island had more big-beaked birds survive?
Ans: Galapagos 1