Book A Ch 5 Test

In a Punnett square, the capital letter represents a dominant allele. Dominant alleles are expressed in the phenotype when present, while recessive alleles are only expressed when there are two copies of the recessive allele. The Punnett square is a tool used to predict the possible genotypes and phenotypes of offspring based on the alleles of the parents.

The combination Tt represents a heterozygous genotype because it contains two different alleles for the same gene. In this case, T and t are two different versions of the gene, with T being dominant and t being recessive. Heterozygous individuals have one copy of each allele, resulting in a mixed phenotype where the dominant allele is expressed, but the recessive allele is also present.

Gene therapy has shown promise in treating cystic fibrosis, a genetic disorder that affects the lungs and digestive system. This therapy involves introducing healthy genes into the patient's cells to replace the faulty ones responsible for the disease. By doing so, it aims to correct the underlying genetic defect and potentially improve the symptoms and quality of life for individuals with cystic fibrosis. While gene therapy has also been explored for other conditions, such as multiple sclerosis, high blood pressure, and the common cold, it has shown particular success and potential in the treatment of cystic fibrosis.

Heredity is the correct answer because it refers to the passing of traits from one generation to another. It involves the transmission of genetic information from parents to offspring, resulting in the inheritance of characteristics such as physical features, behavior, and susceptibility to certain diseases. This process is fundamental to the study of genetics and understanding how traits are passed down through generations.

The genetic make up of an organism refers to the specific combination of genes that it possesses. This combination determines the characteristics and traits of the organism. Therefore, the correct answer is "genotype" as it accurately describes the genetic composition of an organism. Phenotype, on the other hand, refers to the observable physical or biochemical characteristics of an organism, which are influenced by its genotype.

An organism with two alleles that are exactly the same is homozygous. Homozygous refers to a genetic condition where an organism has two identical alleles for a particular trait. In this case, the organism has two alleles that are the same, indicating that it is homozygous for that specific trait.

The correct answer is "sex-linked gene." Hemophilia is a genetic disorder that is caused by a mutation in the gene located on the X chromosome. Since the gene is located on the sex chromosome, it is called a sex-linked gene. This means that the inheritance pattern of hemophilia is different for males and females, as males only have one X chromosome. Females can be carriers of the gene if they have one normal and one mutated X chromosome, while males are more likely to be affected by the disorder if they inherit the mutated X chromosome.

The way an animal looks and behaves is its phenotype. Phenotype refers to the observable characteristics of an organism, including its physical appearance, behavior, and traits. These characteristics are influenced by both genetic factors (genotype) and environmental factors.

Blood type is determined by multiple alleles. This means that there are more than two possible forms of the gene that controls blood type. In humans, there are three alleles for blood type: A, B, and O. The combination of these alleles determines an individual's blood type, such as A, B, AB, or O. This is different from sex-linked genes, which are located on the sex chromosomes, and from polygenic inheritance, which involves the interaction of multiple genes to determine a trait.

Alleles are the different forms of a gene that can exist for a particular trait. They can be dominant or recessive, and individuals inherit two alleles for each gene, one from each parent. These alleles determine the characteristics or traits that an individual will exhibit. Therefore, alleles are the correct answer for this question.

Polygenic inheritance occurs when a group of gene pairs acts together to produce a single trait. Unlike single gene traits, polygenic traits are controlled by multiple genes, each contributing a small effect to the overall phenotype. This results in a wide range of phenotypic variation within a population. Examples of polygenic traits include height, skin color, and intelligence.