Answer:
Some diseases are more common in certain groups of people, such as Caucasians or African Americans because individuals in such ethnic groups often share certain alleles (versions of their genes), that have been passed down to them from common ancestors and a particular genetic disorder may be more frequently seen in such groups if one of these shared genes contains a disease-causing mutation.
Explanation:
Some genetic diseases are frequently seen in certain ethnic groups like Caucasians or African Americans. Individuals in such groups often share certain alleles (versions of their genes), that have been passed down to them from common ancestors and one of these shared genes may contains a disease-causing mutation.
Examples of certain genetic disorders that are more common in particular ethnic groups include the Tay-Sachs disease, which is more common in people of eastern and central Europe (Ashkenazi), Jewish or French Canadian ancestry and the sickle cell disease, which occur among people of African, African American, or Mediterranean heritage.
Some genetic disorders are more common in people whose ancestry can be traced to a particular geographic area. The factors that can lead to development of populations with very different genetic allele frequencies include their geographic origin, selection, patterns of migration, historic events, etc. Certain natural barriers like oceans and other water bodies, high mountains, large deserts, or major cultural factors had prevented communication and interaction between people. So mating was restricted within the group, and this produces genetic marker differences and differences in the presence of specific disease-related alleles.
Phylum Porifera
The phylum Porifera ("pore-bearing") consists of approximately 5,000 species of sponges. These asymmetrical animals have sac-like bodies that lack tissues, and are usually interpreted as representing the cellular level of evolution
Meiosis differs from mitosis in the number of chromosomes in each ending cell. In addition, one of the purposes of meiosis is to reduce the chromosome number in each cell by half and meiosis contains two rounds of division which is meiosis I and meiosis II and ends with four gametes that are not the same genetically.
Answer:
The correct answer is C) It catalyzes the lengthening of telomeres, compensating for the shortening that could occur during replication without telomerase activity.
Explanation:
While replicating, the ends of the chromosomes always lose a part of the ends, therefore, the telomerase catalyzes this growing process, somehow compensating the information that will be lost.
Answer with Explanation:
Hydrogen peroxide is considered<em> "unstable,"</em> thus, storing it in the refrigerator provides two advantages:
1. It slows down thermal decomposition.
- The rate of decomposition slows down when the temperature is lowered. It increases when the temperature rises.
2. It prevents photolytic decomposition.
- Photolytic decomposition happens when hydrogen peroxide is exposed to sunlight or bright light. It therefore increases the rate of reaction. Therefore, hydrogen peroxide should be stored in a <em>cool and dark place</em>, such as the refrigerator.
