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DNA can be synthesized by cells; it can also be synthesized in vitro (outside of cells in a lab). We have looked at DNA synthesis as part of the cell cycle, during PCR (polymerase chain reaction), and during DNA sequencing. Here, we will consider how those processes compare. DNA replication in cells, during PCR and during DNA sequencing results in different products. [p] makes many fragments of different lengths from the DNA, [q] makes many copies of the same length of a single section of DNA, and [r] makes a single copy of all of the DNA. In order to initiate synthesis of a complementary DNA strand, cells use [x], PCR uses [y], and DNA sequencing uses [z]. [a] uses dideoxynucleotides (ddNTPs). ddNTPs are used because [b].

A population is undergoing evolution by natural selection for a trait. What determines whether an allele will become more common in the population?

Max visited the Wild Things (pictured above). In Wild Things, XX individuals produce eggs and are female; XY individuals produce sperm and are male. Several traits in Wild Things are genetically based. the length of horns is genetically based: HH and Hh = curved horns, hh = straight horns having claws on the feet is determine by an X-linked gene. XB is dominant and results in absence of claws; Xb is recessive and results in claws. A female who is heterozygous for both traits and a male without claws who is heterozygous for horns have offspring. Answer the following questions based on this couple. You should start by determining their genotypes and setting up the Punnett squares. The probability that their first offspring would have curved horns is [c]. The probability of their first child having straight horns and NO claws is [d]. The probability of their first child being a female with claws is [e]. Each parent only passes on one of the two alleles they have (Mendel’s Law of Segregation), and the way that the alleles for horns is passed on does not impact the way the allele for claws is passed on (Mendel’s Law of Independent Assortment). These two laws are the result of the way that [f] works.

What is produced by the light reactions of photosynthesis and used in the Calvin cycle? Choose all correct answers.

Choose the mechanism of evolution that best matches the description given.

In a population, the frequency of allele B is 0.4 and the frequency of allele b is 0.6. What percentage of individuals in the population will have the genotype BB if the population is in Hardy-Weinberg equilibrium?

Use the molecules above and your knowledge of biological molecules and cells to answer the following questions. Questions may have a single answer or more than one answer. Molecule [g] could be used to synthesize DNA, which occurs during [h]. Molecule [a] could be used to synthesize RNA, which occurs during the process of [b]. Molecule [c] could be used to synthesize a protein, which occurs during the process of [d]. Molecule [e] can be used as a source of energy or to build polysaccharides. The feature that characterizes all lipids is [x].

Hydrogen ion channels are added to the inner mitochondrial membrane. What impact would this have on ATP production during cellular respiration?

Both prokaryotic and eukaryotic cells can “turn on” (activate expression of) multiple genes at the same time that are all needed for a particular metabolic pathway or process. In prokaryotic cells, this is often because the genes are [a]; in eukaryotic cells, this is often because the genes are [b].

The Calvin cycle of photosynthesis converts inorganic carbon to organic carbon, synthesizing a 3-carbon sugar. Where does the carbon used in the Calvin cycle come from?