Photosynthesis Experiment - Meiosis and Mitosis

Published: 2021-06-29 06:45:18
essay essay

Category: Science

Type of paper: Essay

This essay has been submitted by a student. This is not an example of the work written by our professional essay writers.

Hey! We can write a custom essay for you.

All possible types of assignments. Written by academics

Chapter 2: Genetics

Mendelian Genetics
When Gregor Mendel began his hybridization experiments with pea plants in 1856, knowledge of how heredity works was limited. If two organisms of different height produced offspring, it was assumed that the offspring's height would be somewhere between the height of the two parents. This notion of blending inheritance presented a significant obstacle for the acceptance of the theory of natural selection, since variation would be removed from a population by being blended into nonexistence.

However, for some characteristics -- discrete traits -- inheritance did not produce a state of being between the parents. The children of a brown-eyed father and blue-eyed mother do not end up with an intermediate eye color; rather, children inherit the eye color of a single parent. It was with these types of characteristics that Mendel performed his famous botanical experiments. After carefully selecting pea plants to breed true for particular traits, he then cross-bred strains with conflicting phenotypes (observable physical characteristics). Most importantly for those who were to follow him, he meticulously catalogued the results of these experiments.

Meiosis and Mitosis
The processes of meiosis (the production of sex cells) and mitosis (cell division) are both integral operations necessary to an organism's survival and reproduction. Mitotic divisions occur throughout the body; the results of mitotic division are two daughter cells, each containing a diploid set of chromosomes. Meiosis, however, only occurs within the sex cells of an organism. This process initially divide one cell into two, each with a diploid set of chromosomes. However, this cell generation divides once again, without a corresponding division of DNA, resulting in the final product - the egg or sperm - containing a haploid (single) set of chromosomes. Additionally, during the process of meiosis, homologous chromosomes may exchange material in a genetic recombination event called crossing over. Crossing over is one of the ways that, with each subsequent generation, genes are constantly reshuffled. The reformulation of novel combinations produces the variation necessary for natural selection to operate.
Follow these links to view animated demonstrations of meiosis and mitosis.

Warning! This essay is not original. Get 100% unique essay within 45 seconds!


We can write your paper just for 11.99$

i want to copy...

This essay has been submitted by a student and contain not unique content

People also read