The right answer is metaphase II.
The process is performed in two nuclear and cytoplasmic divisions, called first and second meiotic division or simply meiosis I and meiosis II. Both include prophase, metaphase, anaphase, and telophase. First division prophase is long and consists of 5 stages: leptotene, zygotene, pachytene, diplotene, and diakinesis. It is at this point that genetic recombination takes place at the level of chiasmus.
During meiosis I, the members of each homologous pair of chromosomes are paired during prophase, forming bivalents. During this phase, a protein structure, called synaptonemal complex form, allows recombination between homologous chromosomes. Subsequently, a large condensation of the bivalent chromosomes occurs and go to the metaphase plate during the first metaphase, resulting in the migration of n chromosomes to each of the poles during the first anaphase. This reduction division is responsible for maintaining the number of chromosomes characteristic of each species.
In meiosis II, as in mitosis, the sister chromatids comprising each chromosome are separated and distributed between the nuclei of the daughter cells. Between these two successive steps, there is no DNA replication. The maturation of the daughter cells will result in the gametes.
Answer and Explanation:
The cell division cycle is responsible for increasing and maintaining cell number and size. This cycle is an essential feature of living organisms. There are four phases of cell division mitotic phase (M phase), growth phase 1 (G1), growth phase 2 (G2), and synthesis phase (S). One phase of the cell cycle ends, and the other starts; this is named a phase transition—a unidirectional alteration in the cell cycle phases. During G1, G2, and S phase cell grows and during the M phase cell divides. There are two models of cell reproduction as the clock model and the domino model. The domino model implies that cell division phases must occur in a distinct order and at a definite time. The domino model recommends that the cell cycle events are independent, while the clock model shows that the effectiveness of mitosis entrance was not persuaded by other actions.
Organisms that originated in a certain geographic region and can only be found in that region are said to be endemic.
Explanation:
Endemic organisms are taxonomic species (plants and animals) which originates and distributed only in specific geographic regions. This state of evolution is called endemism.
They are said to be native or indigenous to that particular region which can be an ecological habitat, an entire nation, an island, a mountain range etc. Certain parts are known for majority of their species being endemic like St. Helen Island, New Caledonia Island, Hawaiian Islands, Southern regions of Africa, and Australia.
The species becomes endemic to a particular region because of the presence of certain bio-geographical environmental qualities of that habitat which are favorable to that species.
When these conditions become unfavorable, then species becomes restricted leading to endangerment or extinction of the species.
Examples:
- Kangaroo - Australia
- Nilgiri Tahr, - Nilgiri Hills, India
- The Redwood trees of West Coast of the USA
- Plants like kalo, sumac of Hawaii
