(Fundação de Estudos Inaciana 2013) - Question Easy of Biology

Variation of combinations of all environmental variables (biotic and abiotic) under which a species or population can persist is the definition of:

The tissues of the human body perform specific functions and are organized into systems that ensure the organism's homeostasis. Imagine that a scientist, while studying the effects of a disease that affects skeletal muscle tissue, observed that, as a result of the disease, the contraction capacity of the muscle fibers was compromised. Based on this situation, describe: 1) The relationship between the structure of muscle fibers and their contractile function, including the main cellular components involved in this process. 2) Explain how a change in a tissue such as skeletal muscle can affect the functioning of other systems in the human body, considering the interdependence between tissues and systems for the maintenance of health.

The excreta produced by animals also help maintain environmental health as they serve as a source of nutrients for other living beings present in the animal's environment, thus contributing to the naturally established food chain in that ecosystem. What is the main function of these excreta in this context?

In an experiment with Drosophila melanogaster, a researcher observed that the gray-bodied fly (gene A) and short wings (gene B) were frequently inherited together, while the black-bodied fly and long wings were also commonly observed together. After crosses and analyses, the researcher concluded that genes A and B demonstrate a pattern of linkage and that the recombination frequency between them is 10%. What is the definition of linkage and how can the recombination frequency between genes A and B be used to determine the genetic distance between them in centimorgan map units (cM)?