Answer:
A substance is pure if it is a single substance, and it is made up of only one type of particle. If there is more than one substance, and therefore more than one type of particle, it is a mechanical mixture, the particles can be easily distinguished, due to their non-uniform composition. The composition of a mechanical mixture is variable and their components may be separated by physical or mechanical means because they are not chemically bound.
Explanation:
A pure substance is one that has a composition and characteristic properties that do not change, whatever the physical conditions in which it is found; that is, the physical transformations do not affect it. In other words, pure substances will be made up of particles that are identical to each other. Mechanical mixture are the result of the physical union of two or more substances which are called components, these can be elements or compounds, whose particles do not mix uniformly. The components of the mixtures have different properties, such as the state of aggregation, the density or the solubility. These properties allow substances to be identified and facilitate the separation of the components of a mixture, that is, through physical or mechanical processes we can isolate and obtain the components that make up the mechanical mixtures.
Answer:
Sex determination may be defined as the phenomena of determining the sex whether the organism is male, female or hermaphrodite. Different methods of sex determination are present in different organism.
In case of humans, the sex chromosome of an individual with XY is male whereas XX is female. Humans male are heterogametic. In case of birds the chromosome with ZZ are males (homogametic) whereas ZW is female. In case of Drosophila XY and XO flies are males , while XX, XXY, and XXYY flies are females.
Answer:
1. 20 chromosomes
2. 10 chromosomes
3. 10 chromosomes
Explanation:
1. The process of mitosis results in the two daughter cells from the same parental cell with exactly the same genetic material. Thus the two cells contain the same number of chromosomes as the parent cell. Therefore if a cell with 20 chromosomes undergoes mitosis will result in the 20 chromosomes.
2. During meiosis I two daughter cells are formed with different ploidy levels as the number of the chromosome reduces to half. Therefore the cell with 20 chromosomes results in two cells with 10 chromosomes.
3. During meiosis II, the two daughter cells formed from meiosis I result in the formation of two more daughter cells with an exact number of chromosome number that is 10 chromosomes.
Answer:
it is the part visible to the human eye unless it rains.