Explain the mendel''s laws in genetics, Biology

Assignment Help:

Explain the Mendel's Laws in genetics?

Based on the results of his experiments, Mendel proposed three laws regarding the inheritance of traits: the Law of Segregation, the Law of Independent Assortment, and the Law of Dominance.

The first principle proposed by Mendel, the Law of Segregation, states that "factors" responsible for inheritance of traits remain separate in the offspring, rather than blending . Because traits not apparent in the F1 generation reappeared in the F2 generation, and the F2 generation also had two factors, Mendel concluded that each parent carried two factors that segregate, or separate, during the formation of sperm or egg cells so that they each carry only one factor; therefore the offspring had two factors, the same as the parent.
Since Mendel studied a number of traits, he found that alleles governing different traits, such as position of flowers along the stem; position, shape, and color of the pod; height of the plant; seed texture, seed color, and seed coat color, segregate independently from the alleles that govern another trait. This formed the basis of the second principle, the Law of Independent Assortment. We will see that this law applies only to genes found on different chromosomes.

The third principle, the Law of Dominance, was a result of Mendel's discovery that when two strains were cross-pollinated, one factor in a pair, the dominant factor, may mask the other, so that the dominant trait is always observed in the F1 generation. He called a factor recessive if the trait did not appear until the F2 generation. Some traits were found to exhibit incomplete dominance; that is, heterozygous plants had phenotypes intermediate between the dominant and the recessive. An example is a dominant red flowered plant and recessive white-flowered producing pink-flowered offspring. If dominant traits produce different phenotypes, and both appear in heterozygotes, the traits are called codominant.

539_variations on the mendelian theme.png

There are traits such as skin color in humans that have more than two phenotypes and result from contributions from two or more genes. This condition is called polygenic inheritance. In its simplest form, two genes code for the same trait; an example is kernel color in wheat, where two genes have two alleles, R for red pigment and R' for no pigment at all. The resulting phenotypes exhibit incomplete dominance as with heterozygous single alleles, but there are more shades of red because there are more genes contributing to the trait.


Related Discussions:- Explain the mendel''s laws in genetics

List the parameters in which we evaluate implant prosthesis, List the param...

List the parameters under which you will evaluate implant prosthesis The various parameters under which implant prosthesis can be evaluated are: i) Assessment of mobility.

Explain the taxonomic concepts, Q. Explain the taxonomic concepts? The ...

Q. Explain the taxonomic concepts? The history of classification is an exciting aspect of plant taxonomy. The discovery of the use of plants for food and later as medicine bega

Agro industrial-reproductive tract infections, Reproductive tract infection...

Reproductive tract infections The major cause of reproductive tract infections are, improper dry cow nutrition, contamination at calving due to unsanitary calving area; virule

Cracking, Cracking is the process in which large molecules are broken into ...

Cracking is the process in which large molecules are broken into smaller molecules.                      C 10 H 22         C 5 H 12 + C 5 H 10                      C 8 H

Studying leaf arrangements, Studying leaf arrangements Observe as many ...

Studying leaf arrangements Observe as many growing plants as possible by looking down on them from above. Draw sketches of the dissimilar patterns of leaf arrangement.

Biota of oceans - ecosystem, Biota of Oceans - Ecosystem Life in the s...

Biota of Oceans - Ecosystem Life in the sea is not particularly abundant, though the diversity of organisms is very high. Almost every major group of animals and every major g

Psychological theories, Elsie is 75 and enjoys attending the women's Instit...

Elsie is 75 and enjoys attending the women's Institute and doing volunteer work in a local charity shop for a hospice. She is finding herself forgetting small things, and can't alw

What is oligosaccharides , Oligosaccharides are short chains of m...

Oligosaccharides are short chains of monosaccharides linked together by glycosidic bonds. In case of oligosaccharides  linked to proteins (glycoproteins)  or lipids (glycolipids) o

The genetic code within a dna molecule, How is a genetic trait determined b...

How is a genetic trait determined by the genetic code within a DNA molecule? A DNA molecule has 4 dissimilar bases, either CGTA. Any specific combination of these things forms

How are the triglycerides made, Q. How are the triglycerides made? Trig...

Q. How are the triglycerides made? Triglycerides, oils or fats, are made of one molecule of glycerol bound to three molecules of fatty acids. Hydroxyls of each one of the three

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd