Genes And Chromosomes Quiz: MCQ Test

Gender is determined by the presence of specific alleles, xx for females and xy for males. In humans, females have two x chromosomes (xx), while males have one x and one y chromosome (xy). The combination of these chromosomes determines an individual's biological sex. This is because the y chromosome contains the SRY gene, which triggers the development of male reproductive organs and secondary sexual characteristics. Therefore, the presence of xx or xy alleles plays a crucial role in determining an individual's gender.

Humans have 46 chromosomes. Chromosomes are thread-like structures found in the nucleus of cells that carry genetic information. They come in pairs, with each pair consisting of one chromosome from the mother and one from the father. In total, humans have 23 pairs of chromosomes, resulting in a total of 46 chromosomes. This is the correct answer.

Gregor Mendel is the correct answer because he was an Austrian monk and scientist who conducted experiments on pea plants in the mid-19th century. He is considered the father of modern genetics as his experiments laid the foundation for understanding the principles of inheritance. Mendel's work on pea plants demonstrated the existence of dominant and recessive traits, and his findings became the basis for the laws of Mendelian inheritance. His pioneering research paved the way for further advancements in the field of genetics.

Gregor Mendel experimented with pea plants. This is because pea plants are easy to grow, have a short life cycle, and produce a large number of offspring. Mendel used pea plants to study the inheritance of traits and established the fundamental principles of genetics.

A dominant trait refers to a trait that will always be expressed or shown when it is present in an individual's genetic makeup. This means that even if the individual has only one copy of the dominant allele, it will still be visible in their phenotype. In contrast, a recessive trait would require two copies of the recessive allele for it to be expressed. Therefore, a dominant trait will always be observable in an individual, regardless of whether it is inherited from one or both parents.

Males have XY chromosomes. In humans, females have two X chromosomes (XX), while males have one X and one Y chromosome (XY). The presence of the Y chromosome determines the development of male reproductive organs and characteristics. Therefore, the correct answer is XY.

Females have two X chromosomes, which is denoted as "xx". This combination of chromosomes determines the female sex.

The correct order from biggest to smallest is body, organ system, organ, tissue, cell, organelle, chromosomes, genes, DNA. This order follows the hierarchical structure of the human body, starting from the whole body down to the smallest unit of genetic material.

Physical appearance refers to the observable characteristics of an individual, such as their height, hair color, eye color, and facial features. These characteristics are determined by a combination of genetic factors (genotype) and environmental influences. The term "phenotype" specifically refers to the physical traits that are expressed or manifested in an individual as a result of their genetic makeup and environmental interactions. Therefore, phenotype is the correct answer as it accurately describes the concept of physical appearance.

A Punnett square is a drawing used to predict traits. It is a grid used to determine the possible combinations of alleles in the offspring of two parents. By crossing the alleles of the parents, the Punnett square can show the probability of different traits being expressed in the offspring. This tool is commonly used in genetics to understand inheritance patterns and predict the likelihood of certain traits appearing in future generations.

Baldness is determined by a gene in the X chromosome. This means that the presence or absence of this gene on the X chromosome can influence whether an individual will experience baldness or not. Since males have one X and one Y chromosome, they have a higher chance of inheriting the baldness gene from their mother, as they only have one X chromosome. Females, on the other hand, have two X chromosomes, so they have a lower chance of inheriting the gene and developing baldness.

Down syndrome is caused by the presence of an extra copy of chromosome 21 in the individual's cells, resulting in a total of 47 chromosomes instead of the usual 46. This additional genetic material affects the development and functioning of the body and brain, leading to the characteristic physical and intellectual disabilities associated with the condition.

The question asks if violence is linked to a genetic disease. The correct answer is "No" because violence is not directly linked to a genetic disease. While certain genetic factors might contribute to certain behaviors or predispositions, violence is a complex behavior influenced by a variety of environmental, social, and psychological factors. It is not solely determined by genetics or a genetic disease.

Humans have 23 pairs of chromosomes. Each pair consists of one chromosome from the mother and one from the father, making a total of 46 chromosomes. These chromosomes contain our genetic information and determine our traits and characteristics.

A purebred refers to an individual organism that has two identical alleles for a specific trait. In this case, the correct answer is "TT" because both alleles are uppercase, indicating that they are the same and therefore purebred. The other options have a combination of uppercase and lowercase alleles, indicating that they are not purebred.

Marfan syndrome is a genetic disorder that affects the connective tissues of the body. One of the most common physical characteristics of individuals with Marfan syndrome is being unusually tall, often referred to as "super tall." This is due to the abnormal growth of the long bones in the body. While other symptoms like migraines, diarrhea, and being unathletic can also be present in some cases, being "super tall" is a distinct trait associated with Marfan syndrome.

Hybridization refers to the process of combining different varieties or species of plants or animals to create offspring with desirable traits. This involves crossing two individuals that are genetically different, resulting in heterozygous offspring. These offspring inherit a combination of genetic traits from both parents, which can lead to increased genetic diversity and potentially improved characteristics.

A trait is considered recessive when it skips random generations. This means that individuals who carry the recessive trait may not exhibit it themselves, but can pass it on to their offspring. The trait may not be seen in every generation, as it can be masked by dominant traits, but can reappear in future generations when two carriers of the recessive trait have children together. Therefore, the fact that the trait skips random generations is a characteristic of a recessive trait.

To mark the dominant trait for a Punnett square, you underline it. Underlining the dominant trait helps to distinguish it from the recessive trait, making it easier to analyze and interpret the results of the Punnett square.

Both B and C are heterozygous because they have a combination of two different alleles for the given trait. In genetics, heterozygous refers to an individual having two different alleles for a particular gene, whereas homozygous refers to having two identical alleles. In this case, both B and C have a combination of dominant and recessive alleles (Tt), making them heterozygous.