Answer: Crossing-over allows the genes that come from each parent to recombine before they are passed on to future generations because chromatids of homologous chromosomes mate and exchange sections of their DNA.
Explanation:
Chromosome crossing-over is the process by which chromatids of homologous chromosomes mate and exchange sections of their DNA during prophase I of meiosis, when pairs of homologous chromosomes, or of the same type, are aligned. The chromatids of the homologous chromosomes break off in the chiasmas and rejoin to allow recombination of the linked genes. So it occurs when regions at chromosome breaks mate and then reconnect to the other chromosome. <u>The result of this process is an exchange of genes, called genetic recombination</u>.
This allows the genes that come from each parent to recombine before they are passed on to future generations. Then, <u>it is an important source of genetic variability</u>, since it involves an exchange of segments between homologous chromosomes during the development of gametes. <u>This process allows that the descendants of an individual are genetically very different</u>, since it is very unlikely that an individual produces two equal gametes, because all of them have different segments of the homologous chromosomes.
Answer:
In an aquatic ecosystem, the plants are present both on the subsurface and bottom bed rock of the aquatic body. These are the producers of the ecosystem because they provide food to the living organism in the lake. In day plants growing on the surface of the water takes up carbon dioxide from the atmosphere which is being absorbed in the water, to conduct the process of photosynthesis. These plants release oxygen, which supports the life of aquatic animals. In this way plants limit the abundance of carbon dioxide in water. But in night plants undergo a process of respiration, which releases carbon dioxide. The abundance of carbon dioxide increases in night along with the carbon dioxide being absorbed from the atmosphere. Therefore, concentration of carbon dioxide increases considerably in night as compared to day.
The correct answers are: groundwater, wetlands, rivers, ponds .
Fresh water includes all water excluding seawater and brackish water. Fresh water is not the same as drinking water.
It is important for many organisms as habitat and living resource, plants and most mammals requires fresh water to live.
