25) when does the synaptonemal complex disappear? ; a) late prophase of meiosis i; b) during fertilization or fusion of gametes; c) early anaphase of meiosis i; d) mid-prophase of meiosis ii; e) late metaphase of meiosis ii

The gene that causes sickle-cell disease is present in a higher percentage of residents of sub-saharan africa than among those of african descent living in the united states. even though this gene causes sickle-cell disease, it also provides some protection from malaria, a serious disease that is widespread in sub-saharan africa but absent in the united states. discuss an evolutionary process that could account for the different percentages of the sickle-cell gene among residents of the two regions.

2. in dragons, a gene on chromosome 1 codes for wing color and a gene on chromosome 2 codes for body color. draw out the stages of meiosis for these two chromosomes from a dragon that is heterozygous for both traits. define your alleles. what are all the possible allele combinations of the gametes produced?

Sea levels are rising due to climate change while increasing numbers of people are moving into coastal areas. to accommodate more people, there has been increased construction of beachfront resorts and condominiums. how is this impacting sea turtle numbers and biodiversity and why? a. the increased human population in coastal areas has meant that more food is available to the turtles (e.g., dropped food, waste from restaurants), which has led to an increase in the numbers and diversity of sea turtles. b. there has been very little change in the numbers and biodiversity of sea turtles because the planet is so vast that they can simply relocate to less crowded beaches. c. this has resulted in a decrease in numbers and diversity of sea turtles because it is restricting available nesting sites, and hence reproduction. d. this has resulted in an increase in numbers and diversity of sea turtles because people are around to protect them from natural predators.