Part IV. Critical Thinking: Short Answer. Briefly answer the questions presented
ID: 194645 • Letter: P
Question
Part IV. Critical Thinking: Short Answer. Briefly answer the questions presented; 3-4 sentences should be enough for a correct response. Please answer the following questions, using the proper terminology: a. 1. Compare and contrast metaphase I with metaphase lI While polyploidy is rare in animals, a few species exist as triploids. These species are usually sterile but can still reproduce asexually via mitosis. Explain why triploid individuals can't produce viable gametes during meiosis but are able to reproduce clonally via mitosis [you may use a diagram to support your answer, but you still need to describe in words the process using the proper terms) b.Explanation / Answer
1.
Metaphase-I:
a. Pairs of chromosomes are aligned at the metaphase plate.
b. Spindle fibers get attached to two centromeres of each chromosome.
Metaphase II
a. Chromosomes are aligned at the metaphase plate.
b. Spindle fibers get attached to one centromere from both ends.
The plane of metaphase plate in metaphase I is perpendicular to that of metaphase plate in metaphase II.
2.
Diploid organisms can produce haploid gametes.
Two sets of chromosomes can align and segregate equally between the daughter cells during meiosis.
If a cell contains more than two sets of chromosomes, it gets difficult to segregate chromosome pairs. The daughter cells may not get equal number of chromosomes leading to their lethality.
Hence, these organisms undergo vegetative reproduction or asexual reproduction which does not involve gamete formation and chromosome reduction.