Write the letter of the correct answer on the line at the left. _ Small changes in genes A. disappear quickly. B. gradually accumulate over time. C. prevent the next generation from developing. D. do not affect future generations.

A 13-year-old child received an inheritance of $5000 per year. This was to be invested and allowed to accumulate until the child reached 21 years of age. The first payment was made on the child’s 13th birthday and the last on the 21st birthday. If the money was invested at 5.7% compounded annually, what did the child receive at age 21?

A spadefoot toad tadpole that develops in a rapidly drying pond is likely to eat many of its brothers and sisters. How can eating its siblings, which share half of an individual's genes, be favored by natural selection?

The height of the seed head in wheat at maturity is determined by several genes. In one variety, the head is just $9$ inches above the ground; in another, it is $33$ inches above the ground. Plants from the $9$-inch variety were crossed to plants from the $33$-inch variety. Among the F$_{1}$, the seed head was 21 inches above the ground. After self-fertilization, the F$_{1}$ plants produced an F$_{2}$ population in which $9$-inch and $33$-inch plants each appeared with a frequency of $1$/$256$.

(a) How many genes are involved in the determination of seed head height in these strains of wheat?

(b) How much does each allele of these genes contribute to seed head height?

(c) If a 21-inch F$_{1}$ plant were crossed to a $9$-inch plant, how often would you expect $18$-inch wheat to occur in the progeny?

With regard to heterosis, would the following statements be consistent with the dominance hypothesis, the overdominance hypothesis, or both?
A. Strains that have been highly inbred have become monomorphic for one or more recessive alleles that are somewhat detrimental to the organism.
B. Hybrid vigor occurs because highly inbred strains are monomorphic for many genes, whereas hybrids are more likely to be heterozygous for those same genes.
C. If a gene exists in two alleles, hybrids are more vigorous because heterozygosity for the gene is more beneficial than homozygosity of either allele.

A eukaryotic donor gene is likely to be expressed in a prokaryotic host organism if (a) the donor gene is a promoter gene (b) the donor gene is transferred along with the genes that turn it on $(c)$ the donor gene is placed beside a gene that is not expressed (d) all of these.

Which of the following was probably the least important factor in bringing about the Cambrian explosion?

a. the emergence of predator-prey relationships

b. an increase in the concentration of atmospheric oxygen

c. the movement of animals onto land

d. the origin of Hox genes

A pink-flowering plant is of genotype RW. If two such plants are crossed, we obtain a red plant (RR) with probability .25, a pink plant (RW or WR) with probability .50, and a white plant (WW) with probability .25, as shown in the table. What is the expected number of W genes present in a crossing of this type?

$$\begin{matrix} \text{Number of W Genes Present} & \text{}\\ \text{}{x_{i}} & \text{}{p_{i}}\\ \text{0} & \text{.25}\\ \text{1} & \text{.50}\\ \text{2} & \text{.25}\\ \end{matrix}$$

An inheritance of $20,000 is divided among three investments yielding a total of$1780 in interest per year. The interest rates for the three investments are 7%, 9%, and 11%. The amounts invested at 9% and 11% are $3000 and$1000 less than the amount invested at 7%, respectively. Find the amount invested at each rate.

Work the following applied problem.

Bill Poole wants to have $20,000 available in 5 years for a down payment on a house. He has inherited$16,000. How much of the inheritance should he invest now to accumulate the $20,000 if he can get an interest rate of 5.5% compounded quarterly?

The model of globin gene evolution suggests that an ancestral gene duplicated and mutated to become $\alpha$ - and $\beta$-globin genes, and then each one was further duplicated and mutated. What features of the data set support the model?

An inheritance of $24,000 is to be divided among three trusts with the second trust receiving twice as much as the first trust. The three trusts pay interest at the rates of 9%, 10%, and 6% annually, respectively, and return a total in interest of$2210 at the end of the first year. How much was invested in each trust?

An inheritance of $\$24,000$ is to be divided among three trusts, with the second trust receiving twice as much as the first trust. The three trusts pay interest at the rates of $9\%$, $10\%$, and $6\%$ annually respectively, and return a total in interest of $\$2210$ at the end of the first year. How much was invested in each trust?

When Mendel conducted his famous hybridization experiments, he used peas with green pods and yellow pods. One experiment involved crossing peas in such a way that 25% (or 145) of the 580 offspring peas were expected to have yellow pods. Instead of getting 145 peas with yellow pods, he obtained 152. Assume that Mendel’s 25% rate is correct. Is there strong evidence to suggest that Mendel’s rate of 25% is incorrect?