Since we are given in the question that this alien population meets the requirements for a Hardy-Weinberg equilibrium, we know it is appropriate to use the Hardy-Weinberg equation to think about genotypes and phenotypes. Recall that the Hardy-Weinberg equation is:

Here, p represents the percentage of dominant alleles in the population, while q represents the percentage of recessive alleles in the population. Since all alleles in the population must be either dominant or recessive, the sum of those percentages is always 1:

With that in mind, we can use the information in the question to determine that p = 0.75 and q = 0.25. The proportion of individuals that are homozygous dominant is given by p x p; that are homozygous recessive, q x q; that are heterozygous, 2 x p x q. Since rounded ear shape is dominant to pointed ear shape, we expect that homozygous dominant and heterozygous individuals will all show the rounded ear phenotype. Let's find the total percentage of those individuals that exist in the whole population:

These means 93.75% of the individuals in this population display rounded ear shape; however, this question asked for the number of individuals, so we want to multiply this proportion by the total number of individuals in the population (given as 4000):

This means that the correct answer is that we can expect 3750 of the 4000 total individuals to show rounded ear shape.

Since we are given in the question that this alien population meets the requirements for a Hardy-Weinberg equilibrium, we know it is appropriate to use the Hardy-Weinberg equation to think about genotypes and phenotypes. Recall that the Hardy-Weinberg equation is:

Here, p represents the percentage of dominant alleles in the population, while q represents the percentage of recessive alleles in the population. Since all alleles in the population must be either dominant or recessive, the sum of those percentages is always 1:

With that in mind, we can use the information in the question to determine that p = 0.75 and q = 0.25. The proportion of individuals that are homozygous dominant is given by p x p; that are homozygous recessive, q x q; that are heterozygous, 2 x p x q. Since pointed ear shape is recessive to rounded ear shape, we expect that only homozygous recessive individuals will show the rounded ear phenotype. Let's find the total percentage of those individuals that exist in the whole population:

These means just 6.25% of the individuals in this population display pointed ear shape; however, this question asked for the number of individuals, so we want to multiply this proportion by the total number of individuals in the population (given as 4000):

This means that the correct answer is that we can expect 250 of the 4000 total individuals to show rounded ear shape.

The correct answer here is AA and Aa. We can figure this out by drawing a punnet square as drawn below: 

As you can see from above, there are only two options from this combination of gene alleles. If you chose any of the other options, try drawing a punnett square by placing the first parents' genes on one end of the table and the other on the top. See if you can match each allele to another one from the other parent. You should obtain the same results as above. 

The correct answer is the bottleneck effect, because this is where a natural or rare disaster wipes out an existing generation to alter the gene pool for future generations. If you chose founder effect it may have been because of the relation to bottleneck. Remember that the founder effect, however, is when the beginning population is very small resulting in a small gene pool from the start of the population. If you chose de-volution, remember that this is the opposite of progressive evolution. Famine is an example of natural disaster, however, does not equate the loss of genes

A karyotype is a diagram that depicts all 23 pairs of chromosomes by showing their shapes relative to one another. The process of karyotyping involves examining chromosomes to identify any genetic problems that could result in a disorder or disease. 

Homologous recombination is a natural process in many organisms that cells use to repair DNA, increase genetic variation of offspring during meiosis, or to transfer DNA between individual in viruses or bacteria. In genetic engineering, a section of chromosomal DNA is replaced with a modified version of that segment. Since specific sequences of DNA are being replaced rather than just inserted between natural occurring sequences, this method allows DNA to be placed in specific location in the cell’s chromosomal DNA.

Viral vectors are modified so that they can infect cells, but they cannot replicate. Viral vectors are also much more efficient at introducing DNA to cells than transformation. Even though the virus has been modified to be harmless, however, the host’s immune system can still attack it, leading to a potentially dangerous immune response. Many viruses randomly insert their DNA into host chromosomes, possibly inserting the DNA in the middle of a host gene and interrupting the gene’s function. If the affected host gene is important in cell replication, DNA repair, or programmed cell death, this could lead to cancer.

Positively charged calcium ions are attracted to both the negatively charged plasmid DNA and the negatively charged plasma membrane, overcoming the usual repulsion between the two and allowing them to bind. Heat shock is used to open pores during the transformation process, so that the bound plasmid DNA can enter the cell. Bacteria defenses generally destroy viral DNA, not bacterial plasmid DNA. Calcium is used as a signal in many cell processes, but this is not the purpose of calcium chloride in transformation. 

A reporter gene is a gene that is introduced to cells along with a gene of interest in order to determine which cells have been successfully transformed. Since both genes are on the same plasmid, if the bacterial colonies after incubation fluoresce green then they also have the gene of interest, which may not be detected as easily. Knockout and knock-in genes refer to genetic changes chromosomal DNA and are not introduced using plasmids. A promoter refers to a part of a gene that regulates its expression.

Bacteria do not perform post-transcriptional modification of mRNA. None of the other answers are actual differences between bacteria and eukaryotes. Bacteria begin translating mRNA into amino acids before transcription has even completed, giving them no opportunity to modify the mRNA transcript before translation. Therefore, a cDNA copy must be made from the already modified mRNA produced by the eukaryotic organism and then introduced into the bacterial cell. That way the bacteria can transcribe and translate the cDNA without having to modify the mRNA transcript.