Biology: What Do You Know About Chromosomal Inheritance?

Explanation
The features of an organism refer to its specific qualities or attributes that distinguish it from other organisms. These characteristics can include physical traits, behaviors, or genetic makeup. This answer is correct because "characteristics" accurately describes the unique qualities of an organism that make it different from others.

Explanation
Characteristics we get from parents have been inherited. Inheritance refers to the transmission of traits or characteristics from parents to their offspring through genetic information. It involves the passing on of genetic material, such as DNA, from one generation to the next. Inherited characteristics can include physical traits, such as eye color or height, as well as certain predispositions or tendencies towards certain diseases or behaviors.

Explanation
Chromosomes are found in the nucleus of a cell. The nucleus is a membrane-bound organelle that contains the cell's genetic material, including chromosomes. Chromosomes are structures made up of DNA and proteins, and they carry the genes that determine an organism's traits. The nucleus provides a protected environment for the chromosomes, allowing them to carry out their functions, such as DNA replication and gene expression, without interference from other cellular components. Therefore, the correct answer is nucleus.

Explanation
Each body cell contains 46 chromosomes. Chromosomes are thread-like structures made up of DNA that carry genetic information. They are found in the nucleus of every cell in the body. In humans, there are 23 pairs of chromosomes, for a total of 46. These chromosomes contain genes that determine our traits and characteristics.

Explanation
The male sex chromosomes are represented by XY. In humans, males have one X chromosome and one Y chromosome, while females have two X chromosomes. The presence of the Y chromosome determines the development of male characteristics. Therefore, XY is the correct representation of male sex chromosomes.

Explanation
Recessive alleles will only work if there are two copies because they require both copies of the gene to be present in order to be expressed. If only one copy of the recessive allele is present, the dominant allele will mask its effects. Therefore, for a recessive allele to be expressed, an individual must inherit two copies of the allele, one from each parent.

Explanation
Cystic fibrosis is a genetic disorder that primarily affects the lungs. It causes the production of thick, sticky mucus that clogs the airways and leads to frequent lung infections. This can result in difficulty breathing, chronic coughing, and reduced lung function. While cystic fibrosis can also affect other organs such as the pancreas, liver, and intestines, the lungs are the most commonly affected and significant organ in this disease.

Explanation
Down syndrome and sickle cell are both genetic disorders that are caused by mutations in the DNA. In Down syndrome, there is an extra copy of chromosome 21, which leads to developmental and intellectual disabilities. Sickle cell disease is caused by a mutation in the gene that codes for hemoglobin, resulting in abnormal red blood cells that can cause pain, organ damage, and other complications. Therefore, mutations are the underlying cause of both conditions.

Explanation
Fossils provide evidence for Darwin's theory of evolution because they are the preserved remains or traces of ancient organisms. By studying fossils, scientists can observe changes in species over time, including the development of new traits and the extinction of others. Fossils also provide a record of the progression of life on Earth, supporting the idea that species have evolved and diversified over millions of years. The other options, such as the bible, old bones, and Jurassic Park, do not provide direct scientific evidence for evolution.

Explanation
Natural selection is the process by which organisms with advantageous traits are more likely to survive and reproduce, passing on those traits to future generations. "Survival of the fittest" refers to the idea that the individuals who are best adapted to their environment, in terms of their physical traits and abilities, are the ones most likely to survive and pass on their genes. It does not refer to wealth, size, or weight, but rather to the overall fitness and adaptability of an organism in its specific environment.