Sister chromosome exchanges are recombination events that occur between homologous chromosomes and are often the result of exposure of the cell to DNA damaging agents.
Cross over, or recombination, is the exchange of chromosome segments between non sister chromatids in meiosis. Crossing over creates new combinations of genes in the gametes that are not found in either parent, contributing to genetic diversity.
Rodolf Virchow was the scientist that studied how wounds heal and proposed that cells come from preexisting cells. Rodolf Virchow was born on 13th of October in the year 1821 and died on 5th of September in the year 1902.He was a German doctor, pathologist, anthropologist, writer, editor and politician. he was a multi faceted person. He became famous because of his discoveries regarding public health. He is also regarded as the Father of modern pathology. He was German by birth. Although he failed in containing the typhus epidemic that occurred in Upper Silesia but his report was valuable in laying the foundation for public health in Germany.
This is cellulose,because humans lack enzymes to break it down
1. Similarities:
they are both processes of cell division by which cells reproduce.
They share several steps of the process(prophase, metaphase, anaphase e telophase, cytokinesis) but meiosis has another division also with those same steps.
In both cases the cell duplicates its DNA by pulling it
apart into two sets, place the sets on each end of the cell, and then
divide down the middle.
Both produce new cells
based on their parent cells' genes.
2. The differences:
Mitosis:
- has 1 division per cycle
- one cell produces 2 new cells
- the genetic information in the mother-cell and the daughter-cells are the same. ( the number of chromosomes is also the same)
- it occurs in somatic cells
Meiosis:
- two divisions per cycle.
- one cell when divides produces 4 new cells
- the new cells have different genetic information. mixes the the genetic material from the
parent cells
- the number of chromosomes of the daughter cells is half of the mother's.
The answer is 300 joules of energy.
An energy pyramid is a presentation of the trophic levels in an ecosystem. Energy from the sun is transferred through the ecosystem by passing through various trophic levels. Roughly 10% of the energy is transferred from one trophic level to the next, thus preventing a large number of trophic levels.
