Answer:
Explanation: Eagles are endotherm and homoeothermic.
Coyote are endotherms and homoeothermic.
Walrus are Endothermic and homoeothermic.
The above organisms maintain constant internal body temperature irrespective of fluctuations in surrounding temperature.
Artic shrimp are ectotherms; and homoeothermic. Despite the fact that it has negligible source of intenal heat, its environmental temperature is relatively stable, therefore it is both ectotherms and homoeothermic.
Butterfly, freshwater catfish, Salamander are Poikilothermic. These organism’s body temperature fluctuates with the immediate surrounding temperature. They lack internal body temperature.
Evolution, it mentioned over several generations.
Answer:
1. They must be removed before sister chromatids or homologous chromosomes can separate
Explanation:
During the S-phase of the cell cycle, not only does DNA have to be replicated, but also newly synthesized DNA molecules have to be connected with each other. This replicated DNA (sister chromatids) remain physically connected with each other from S phase until metaphase. This physical connection is called Sister chromatids cohesion.
Sister chromatid cohesion depends on COHESIN, a tripartite protein complex that forms a ring structure to hold sister chromatids together during mitosis and meiosis. Cohesin regulates the separation of sister chromatids during cell division, either mitosis or meiosis. This sister chromatid cohesion is essential for the biorientation of chromosomes on the mitotic or meiotic metaphase spindle, and is thus an essential prerequisite for chromosome segregation. Without the cohesion, sister chromatids would not be segregated symmetrically between the forming daughter cells, resulting in aneuploidy.
Cohesion is established during S-phase of DNA replication, and the cohesins hold the sister chromatid together after DNA replication until anaphase when the removal of cohesin leads to separation of sister chromatids (meiosis II and mitosis) and homologous chromosomes (meiosis I).
The three ways mutations can occur are
Mutations arise spontaneously at low frequency owing to the chemical instability of purine and pyrimidine bases and to errors during DNA replication. Natural exposure of an organism to certain environmental factors, such as ultraviolet light and chemical carcinogens (e.g., aflatoxin B1), also can cause mutations.
The tropics receive a great amount of direct solar energy, which produces more evaporation<span> than higher latitudes. The warm, moist air rises, condenses into clouds and thunderstorms, and falls back to earth as </span>precipitation<span>.</span>