During Prophase I, which is the first division stage of meiosis I, homologous chromosomes pair up with each chromosome aligning with its homologue partner to form a TETRAD structure. At this stage, segments of each homologous chromosome break and get refixed interchangeably i.e trade parts. This process is called Crossing-over or RECOMBINATION
Crossing-over is the process whereby two chromosomes of a homologous pair (non-sister chromatids) exchange equal segments with each other to form two recombinant chromosomes.
Crossing-over accounts for genetic variation due to the swapping of genetic material. Some of the daughter cells receive daughter chromosomes with recombined alleles. Due to this genetic recombination, the offspring have a different set of alleles and genes than their parents do.
Answer: Organisms depend on other organisms and on the nonliving things in an ecosystem to meet their basic needs for food, water and protection. 3. Plants use energy from the sun to produce their own food from air and water.
chloroplasts work to convert light energy of the sun into sugars that can be used by cells. Its like a solar panel that changes sunlight energy into electric energy. The entire process is called photosynthesis and it all depends on the little green chlorophyll molecules in each chloroplast.
medical waste is most often collected in biohazard bags or containers and incinerated. The heat kills bacteria and other pathogens that would re-infect surfaces, and workers.
