Answer:
4) molecule, cell, organ system, population, ecosystem, biosphere
Explanation:
Various biomolecules such as carbohydrates, proteins, lipids, etc. together make the cells. Cells are the structural and functional units of life. A group of cells destined to perform specific functions makes tissues and various specific tissues together make an organ.
An organized group of tissues and organs that work cooperatively to perform a specialized set of functions is called an organ system. For example, the digestive system includes organs involved in the breakdown of nutrients.
A group of organisms of the same species that live in a defined geographic area at the same time make a population. Ecosystem refers to an interacting system including a biotic community and its nonliving, physical environment. The biosphere includes all of the parts of Earth where life forms exist and include the atmosphere, the hydrosphere and the lithosphere.
Answer:
b, negative ... positive
Explanation:
Gel electrophoresis is a method used in molecular biology for DNA analysis. This method includes the separation of DNA fragments through the gel according to their size or shape under the influence of aplid electric current. Since the fragments of DNA are negatively charged, they will move from negative to positive end.
Small fragments will move faster than larger ones.
One of the major source of error is contamination of the DNA sample. This refers to the presence of foreign DNA in the sample of interest. As a consequence, the gel will have more bands.
Another errors might appear as a result of wrong concentration of the gel, wrong buffer pH, high/low concentration of dye etc.
Answer:
C.) 26 - 13
Explanation:
During mitosis, DNA is replicated during the S phase so that when the cell divides the daughter cells will have the same number of chromosomes that the parent cell had.
DNA replication also occurs during meiosis, but the cell divides twice, so the daughter cells will have half the number of chromosomes that the parent cell had. This is because the daughter cells are sex cells, which combine with another sex cell (either an egg or a sperm) to form one cell with a combined chromosome number.
Performance of physical activity, intake of food and water, body temperature, illnesses or diseases, etc.
Answer:
(1) roots, (2) stems, (3) leaves, and (4) flowers
Explanation:
