Drosophila melanogaster, the common fruit fly, is frequently utilized for genetic studies due to its simple food requirements, hardy nature, and because it completes its life cycle within 12 days at room temperature. This particular fly species has four pairs of chromosomes with traits that have been studied and observed to be inherited in a Mendelian fashion.

The predictive capacity of Mendelian genetics depends on traits whose physiological characteristics, know as phenotypes, are determined by genetic combinations of alleles, known as genotypes. The exhibition of observable traits is determined by the combination of two alleles for a specific characteristic. For example, the dominant allele for the wild type red eye color is E and the recessive sepia-brown color is e. Likewise, the dominant allele for long wings is W and the recessive allele for short wings is w. When a dominant allele is present with a recessive one, the organism physically exhibits the trait of the dominant allele and the organism is known as heterozygous for that trait. If an organism has two dominant or two recessive alleles for a particular trait, it is known as homozygous for that trait. Only when two recessive alleles are present does the organism physically exhibit the trait of the recessive allele. Heterozygous individuals are often known as carriers because the dominant allele phenotype masks the recessive allele phenotype and the organism can carry the recessive allele without exhibiting any of its physical traits.

Study 1

A researcher wants to study the inheritance of eye color in fruit flies. The scientist mates a homozygous recessive (ee) group with a homozygous dominant (EE) group in order to obtain the F1 Generation. Two members of the F1 Generation were then mated in order to obtain the F2 Generation (Table 1).

Table 1

Study 2

A researcher decided to perform a dihybrid cross of fruit flies possessing red eyes and long wings with fruit flies possessing sepia-brown eyes and short wings. The scientist bred homozygous dominant flies with homozygous recessive flies in the F1 Generation. The members of the F1 Generation were then mated in order to obtain the F2 Generation (Table 2).

Table 2

A researcher mates two groups of fruit flies: one homozygous recessive for short wings and one homozygous dominant for long wings. Two of the heterozygous offspring of the F1 Generation are mated. What genotypic possibilities will there be in the F2 generation?

Drosophila melanogaster, the common fruit fly, is frequently utilized for genetic studies due to its simple food requirements, hardy nature, and because it completes its life cycle within 12 days at room temperature. This particular fly species has four pairs of chromosomes with traits that have been studied and observed to be inherited in a Mendelian fashion.

The predictive capacity of Mendelian genetics depends on traits whose physiological characteristics, know as phenotypes, are determined by genetic combinations of alleles, known as genotypes. The exhibition of observable traits is determined by the combination of two alleles for a specific characteristic. For example, the dominant allele for the wild type red eye color is E and the recessive sepia-brown color is e. Likewise, the dominant allele for long wings is W and the recessive allele for short wings is w. When a dominant allele is present with a recessive one, the organism physically exhibits the trait of the dominant allele and the organism is known as heterozygous for that trait. If an organism has two dominant or two recessive alleles for a particular trait, it is known as homozygous for that trait. Only when two recessive alleles are present does the organism physically exhibit the trait of the recessive allele. Heterozygous individuals are often known as carriers because the dominant allele phenotype masks the recessive allele phenotype and the organism can carry the recessive allele without exhibiting any of its physical traits.

Study 1

A researcher wants to study the inheritance of eye color in fruit flies. The scientist mates a homozygous recessive (ee) group with a homozygous dominant (EE) group in order to obtain the F1 Generation. Two members of the F1 Generation were then mated in order to obtain the F2 Generation (Table 1).

Table 1

Study 2

A researcher decided to perform a dihybrid cross of fruit flies possessing red eyes and long wings with fruit flies possessing sepia-brown eyes and short wings. The scientist bred homozygous dominant flies with homozygous recessive flies in the F1 Generation. The members of the F1 Generation were then mated in order to obtain the F2 Generation (Table 2).

Table 2

In Study 1, what proportion of the fruit flies in the F2 Generation will express the sepia-brown eye color phenotype?

Drosophila melanogaster, the common fruit fly, is frequently utilized for genetic studies due to its simple food requirements, hardy nature, and because it completes its life cycle within 12 days at room temperature. This particular fly species has four pairs of chromosomes with traits that have been studied and observed to be inherited in a Mendelian fashion.

The predictive capacity of Mendelian genetics depends on traits whose physiological characteristics, know as phenotypes, are determined by genetic combinations of alleles, known as genotypes. The exhibition of observable traits is determined by the combination of two alleles for a specific characteristic. For example, the dominant allele for the wild type red eye color is E and the recessive sepia-brown color is e. Likewise, the dominant allele for long wings is W and the recessive allele for short wings is w. When a dominant allele is present with a recessive one, the organism physically exhibits the trait of the dominant allele and the organism is known as heterozygous for that trait. If an organism has two dominant or two recessive alleles for a particular trait, it is known as homozygous for that trait. Only when two recessive alleles are present does the organism physically exhibit the trait of the recessive allele. Heterozygous individuals are often known as carriers because the dominant allele phenotype masks the recessive allele phenotype and the organism can carry the recessive allele without exhibiting any of its physical traits.

Study 1

A researcher wants to study the inheritance of eye color in fruit flies. The scientist mates a homozygous recessive (ee) group with a homozygous dominant (EE) group in order to obtain the F1 Generation. Two members of the F1 Generation were then mated in order to obtain the F2 Generation (Table 1).

Table 1

Study 2

A researcher decided to perform a dihybrid cross of fruit flies possessing red eyes and long wings with fruit flies possessing sepia-brown eyes and short wings. The scientist bred homozygous dominant flies with homozygous recessive flies in the F1 Generation. The members of the F1 Generation were then mated in order to obtain the F2 Generation (Table 2).

Table 2

In Study 1, what proportion of the fruit flies in the F2 Generation possess a heterozygous allele combination for eye color?

Drosophila melanogaster, the common fruit fly, is frequently utilized for genetic studies due to its simple food requirements, hardy nature, and because it completes its life cycle within 12 days at room temperature. This particular fly species has four pairs of chromosomes with traits that have been studied and observed to be inherited in a Mendelian fashion.

The predictive capacity of Mendelian genetics depends on traits whose physiological characteristics, know as phenotypes, are determined by genetic combinations of alleles, known as genotypes. The exhibition of observable traits is determined by the combination of two alleles for a specific characteristic. For example, the dominant allele for the wild type red eye color is E and the recessive sepia-brown color is e. Likewise, the dominant allele for long wings is W and the recessive allele for short wings is w. When a dominant allele is present with a recessive one, the organism physically exhibits the trait of the dominant allele and the organism is known as heterozygous for that trait. If an organism has two dominant or two recessive alleles for a particular trait, it is known as homozygous for that trait. Only when two recessive alleles are present does the organism physically exhibit the trait of the recessive allele. Heterozygous individuals are often known as carriers because the dominant allele phenotype masks the recessive allele phenotype and the organism can carry the recessive allele without exhibiting any of its physical traits.

Study 1

A researcher wants to study the inheritance of eye color in fruit flies. The scientist mates a homozygous recessive (ee) group with a homozygous dominant (EE) group in order to obtain the F1 Generation. Two members of the F1 Generation were then mated in order to obtain the F2 Generation (Table 1).

Table 1

Study 2

A researcher decided to perform a dihybrid cross of fruit flies possessing red eyes and long wings with fruit flies possessing sepia-brown eyes and short wings. The scientist bred homozygous dominant flies with homozygous recessive flies in the F1 Generation. The members of the F1 Generation were then mated in order to obtain the F2 Generation (Table 2).

Table 2

In Study 1, what proportion of the fruit flies in the F1 Generation exhibited wild type red eyes?

The process by which cells divide and multiply is known as the cell cycle. This cycle consist of two main phases: interphase and mitosis. Each phase consists of a series of clearly defined and observable steps. At the conclusion of the cycle, each parent cell produces two genetically identical daughter cells that may undergo a cycle of replication.

Roughly 90 percent of the cell cycle is spent in interphase. Interphase is comprised of three main steps: the first gap phase, the synthesis phase, and the second gap phase. The initial gap phase is a period of cellular preparation in which the cell increases in size and readies itself for DNA synthesis. In the synthesis phase, DNA replication occurs. In the second gap phase the cell grows in size and prepares for cellular division in the mitotic phase. At the end of each gap phase the cell has to pass regulatory checkpoints to ensure proper cell growth and environmental conditions.

Mitosis is a form of nuclear division and is broken down into five distinct phases. During prophase, the genetic material contained in chromatin condenses into distinct chromosomes. Prometaphase is marked by the breakdown of the nuclear envelope and the formation of centrosomes at the poles of the cell. During metaphase, kinetochores attached to the microtubules migrate the chromosomes to the center of the cell. A checkpoint ensures that the chromosomes are aligned on the center and halts the cycle if an error occurs. Anaphase occurs when chromosomes break apart at their center or centromere and sister chromatids move to opposite ends of the cell. Last, telophase and cytokinesis occurs as nuclear membranes form in each new daughter cell and when chromosomes unwind into loose chromatin. Cytokinesis is defined as the division of the each cell’s cytoplasm and organelles. The conclusion of the cell cycle results in the production of two genetically identical daughter cells.

Study 1

Scientists study the role of the cell cycle in the cells of a growing onion. They investigate the number of cells in each phase of the cycle in two parts of the onion: the fast growing root and the slow growing bulb. They record their observations and calculate the percentage of cells undergoing each phase (See Figure 1 andFigure 2).

Figure 1

Figure 2

If investigators counted a total of 1,400 bulb cells then how many were in interphase according to Figure 2?

The process by which cells divide and multiply is known as the cell cycle. This cycle consist of two main phases: interphase and mitosis. Each phase consists of a series of clearly defined and observable steps. At the conclusion of the cycle, each parent cell produces two genetically identical daughter cells that may undergo a cycle of replication.

Roughly 90 percent of the cell cycle is spent in interphase. Interphase is comprised of three main steps: the first gap phase, the synthesis phase, and the second gap phase. The initial gap phase is a period of cellular preparation in which the cell increases in size and readies itself for DNA synthesis. In the synthesis phase, DNA replication occurs. In the second gap phase the cell grows in size and prepares for cellular division in the mitotic phase. At the end of each gap phase the cell has to pass regulatory checkpoints to ensure proper cell growth and environmental conditions.

Mitosis is a form of nuclear division and is broken down into five distinct phases. During prophase, the genetic material contained in chromatin condenses into distinct chromosomes. Prometaphase is marked by the breakdown of the nuclear envelope and the formation of centrosomes at the poles of the cell. During metaphase, kinetochores attached to the microtubules migrate the chromosomes to the center of the cell. A checkpoint ensures that the chromosomes are aligned on the center and halts the cycle if an error occurs. Anaphase occurs when chromosomes break apart at their center or centromere and sister chromatids move to opposite ends of the cell. Last, telophase and cytokinesis occurs as nuclear membranes form in each new daughter cell and when chromosomes unwind into loose chromatin. Cytokinesis is defined as the division of the each cell’s cytoplasm and organelles. The conclusion of the cell cycle results in the production of two genetically identical daughter cells.

Study 1

Scientists study the role of the cell cycle in the cells of a growing onion. They investigate the number of cells in each phase of the cycle in two parts of the onion: the fast growing root and the slow growing bulb. They record their observations and calculate the percentage of cells undergoing each phase (See Figure 1 and Figure 2).

Figure 1

Figure 2

If the investigators counted a total of 1,000 root cells then how many were interphase according to Figure 1?

The process by which cells divide and multiply is known as the cell cycle. This cycle consist of two main phases: interphase and mitosis. Each phase consists of a series of clearly defined and observable steps. At the conclusion of the cycle, each parent cell produces two genetically identical daughter cells that may undergo a cycle of replication.

Roughly 90 percent of the cell cycle is spent in interphase. Interphase is comprised of three main steps: the first gap phase, the synthesis phase, and the second gap phase. The initial gap phase is a period of cellular preparation in which the cell increases in size and readies itself for DNA synthesis. In the synthesis phase, DNA replication occurs. In the second gap phase the cell grows in size and prepares for cellular division in the mitotic phase. At the end of each gap phase the cell has to pass regulatory checkpoints to ensure proper cell growth and environmental conditions.

Mitosis is a form of nuclear division and is broken down into five distinct phases. During prophase, the genetic material contained in chromatin condenses into distinct chromosomes. Prometaphase is marked by the breakdown of the nuclear envelope and the formation of centrosomes at the poles of the cell. During metaphase, kinetochores attached to the microtubules migrate the chromosomes to the center of the cell. A checkpoint ensures that the chromosomes are aligned on the center and halts the cycle if an error occurs. Anaphase occurs when chromosomes break apart at their center or centromere and sister chromatids move to opposite ends of the cell. Last, telophase and cytokinesis occurs as nuclear membranes form in each new daughter cell and when chromosomes unwind into loose chromatin. Cytokinesis is defined as the division of the each cell’s cytoplasm and organelles. The conclusion of the cell cycle results in the production of two genetically identical daughter cells.

Study 1

Scientists study the role of the cell cycle in the cells of a growing onion. They investigate the number of cells in each phase of the cycle in two parts of the onion: the fast growing root and the slow growing bulb. They record their observations and calculate the percentage of cells undergoing each phase (See Figure 1 andFigure 2).

Figure 1

Figure 2

What percentage of the cells in Figure 1 were in mitosis? 

The process by which cells divide and multiply is known as the cell cycle. This cycle consist of two main phases: interphase and mitosis. Each phase consists of a series of clearly defined and observable steps. At the conclusion of the cycle, each parent cell produces two genetically identical daughter cells that may undergo a cycle of replication.

Roughly 90 percent of the cell cycle is spent in interphase. Interphase is comprised of three main steps: the first gap phase, the synthesis phase, and the second gap phase. The initial gap phase is a period of cellular preparation in which the cell increases in size and readies itself for DNA synthesis. In the synthesis phase, DNA replication occurs. In the second gap phase the cell grows in size and prepares for cellular division in the mitotic phase. At the end of each gap phase the cell has to pass regulatory checkpoints to ensure proper cell growth and environmental conditions.

Mitosis is a form of nuclear division and is broken down into five distinct phases. During prophase, the genetic material contained in chromatin condenses into distinct chromosomes. Prometaphase is marked by the breakdown of the nuclear envelope and the formation of centrosomes at the poles of the cell. During metaphase, kinetochores attached to the microtubules migrate the chromosomes to the center of the cell. A checkpoint ensures that the chromosomes are aligned on the center and halts the cycle if an error occurs. Anaphase occurs when chromosomes break apart at their center or centromere and sister chromatids move to opposite ends of the cell. Last, telophase and cytokinesis occurs as nuclear membranes form in each new daughter cell and when chromosomes unwind into loose chromatin. Cytokinesis is defined as the division of the each cell’s cytoplasm and organelles. The conclusion of the cell cycle results in the production of two genetically identical daughter cells.

Study 1

Scientists study the role of the cell cycle in the cells of a growing onion. They investigate the number of cells in each phase of the cycle in two parts of the onion: the fast growing root and the slow growing bulb. They record their observations and calculate the percentage of cells undergoing each phase (See Figure 1 andFigure 2).

Figure 1

Figure 2

If investigators counted 1,400 bulb cells then how many were undergoing mitosis in Figure 2?

The process by which cells divide and multiply is known as the cell cycle. This cycle consist of two main phases: interphase and mitosis. Each phase consists of a series of clearly defined and observable steps. At the conclusion of the cycle, each parent cell produces two genetically identical daughter cells that may undergo a cycle of replication.

Roughly 90 percent of the cell cycle is spent in interphase. Interphase is comprised of three main steps: the first gap phase, the synthesis phase, and the second gap phase. The initial gap phase is a period of cellular preparation in which the cell increases in size and readies itself for DNA synthesis. In the synthesis phase, DNA replication occurs. In the second gap phase the cell grows in size and prepares for cellular division in the mitotic phase. At the end of each gap phase the cell has to pass regulatory checkpoints to ensure proper cell growth and environmental conditions.

Mitosis is a form of nuclear division and is broken down into five distinct phases. During prophase, the genetic material contained in chromatin condenses into distinct chromosomes. Prometaphase is marked by the breakdown of the nuclear envelope and the formation of centrosomes at the poles of the cell. During metaphase, kinetochores attached to the microtubules migrate the chromosomes to the center of the cell. A checkpoint ensures that the chromosomes are aligned on the center and halts the cycle if an error occurs. Anaphase occurs when chromosomes break apart at their center or centromere and sister chromatids move to opposite ends of the cell. Last, telophase and cytokinesis occurs as nuclear membranes form in each new daughter cell and when chromosomes unwind into loose chromatin. Cytokinesis is defined as the division of the each cell’s cytoplasm and organelles. The conclusion of the cell cycle results in the production of two genetically identical daughter cells.

Study 1

Scientists study the role of the cell cycle in the cells of a growing onion. They investigate the number of cells in each phase of the cycle in two parts of the onion: the fast growing root and the slow growing bulb. They record their observations and calculate the percentage of cells undergoing each phase (See Figure 1 andFigure 2).

Figure 1

Figure 2

Why would scientists classify the root cells as "fast growing" when compared to the bulb cells in Figure 1 and 2?

Vaccinations have become a controversial topic in the United States. Currently the US Food and Drug Administration (FDA) regulates all vaccines. The federal government does not mandate vaccinations for any individual; however, all states require vaccinations for children entering public school. There are several types of vaccines—live attenuated vaccines, inactivated vaccines, subunit vaccines, toxoid vaccines, and conjugate vaccines, just to name a few. All of these vaccines have the shared purpose of exposing the host body to antigens of a specific disease. When the body receives the antigens, the immune system is activated, remembering the antigens. The next time the individual is exposed to the disease, the body will remember the antigen and have a better probability of not getting infected. Two scientists below discuss their belief on vaccines.

Scientist 1

Vaccines have saved many lives. The risks of not being vaccinated far outweigh the risks of adverse vaccine reactions. Reports linking autism to vaccines have been evaluated by the CDC, which states there is no scientific link between autism and vaccines. The second leading cancer killer in women is cervical cancer. The HPV vaccine protects against the two most common strains causing cancer. This is an example of a vaccine that does much more good than bad. Vaccines also reduce the amount of money spent on healthcare, because the preventative cost of a vaccine is much cheaper than the cost of treating an infected person. The only time a vaccine should not be administered is if the chance of the individual coming into contact with the disease is so rare it is not worth the potential of adverse reactions.

 Scientist 2

Many vaccines nowadays are extraneous. Vaccines for diseases like whooping cough and scarlet fever were once necessary but now outdated. Modern updates on hygiene, waste management, and water filtration have resulted in significantly decreased chances of infection. In addition, diseases like rotavirus have an infection period of a few days, and the main symptom is dehydration. Modern medicine can easily treat severe dehydration, and the risk of rotavirus infection is very slim; therefore, the results of infection are far milder than the results of an adverse reaction. Vaccines for children can cause extremely dangerous adverse reactions. This includes anaphylactic shock, paralysis, and death. While scientists have not been able to conclusively prove this, many believe that these reactions are related to the age of the host and the lack of a developed immune systemor neural network. Vaccines suppress the immune system, which can lead to autoimmune disorders. In addition, vaccines can congest the lymphatic system with proteins molecules from the vaccines; therefore, I would recommend requirements for vaccination to take place at a later stage in a child’s development.

What is the key molecule behind vaccines?