Nondisjunction is the failure of chromosones to seperate correctly during cell division. Nondisjucntion during meiosis violates Mendels Law of Segregation, producing gametes with an incorrect number of chromosones. The two types of nondisjunction during meiosis in females are shown in the image. The genetic contents of the zygotes that would result from the fertilization of each egg by a sperm are also shown.

For an organism with a haploid number of n=8, what percentage of the gametes resulting from a nondisjunction event of one chromosone pair during meiosis 1 will have only seven chromosones?

A: 25%
B: 50%
C: 75%
D: 0%

Humans are believed to have evolved in coastal regions in east africa. the region had an abundant supply of fish for early humanoids to eat. when scientists analyze the fads gene they see an interesting pattern. people whose families have lived in this area of east africa for generation show a high level of diversity in alleles for the fads gene. conversely, people whose families had migrated inland a moderate distance from sources of fish showed a much lower diversity for fads gene alleles. additionally, the fads alleles found in people whose family has lived inland for generation are almost all gene alleles which produce fads proteins with a high level of function and activity. how do anthropologists explain this?

Ihave no idea how to solve these. plus there's another question that is 2) a 10 kilogram meteorite is collected in space and brought back to earth. it is composed of 1.25 kg of uranium-238 and 8.75 kg of lead-206. how many u-238 half lives have passed? what is the approximate age of the meteorite?

The big bang theory suggest that the universe is about - 300 million years old - 4.6 billion years old - 30 billion years old - 13 billion years old