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the terms phenotype and genotype. Phenotype refers to the observed traits--the actual appearance of an organism. Genotype is the actual genetic code inherited from parents that produces visible differences. The phenotype may change with time, but the genotype is fixed for life.In 1909, there were as many terms to describe what biological component caused inheritance as there were heredity theories. Johannsen clarified the terminology by coining the term gene to describe a unit of inheritance. He felt it was a term that was not associated with any of the many theories that existed to explain evolution. And he didn't stop there. Johannsen came up with this terms.

2007-03-07 11:51:51 · answer #1 · answered by Byzantino 7 · 2 1

genotype is an outline of the allels of the organism so in case you describe a mutant allel and assume something of the animal is wildtype you're describing the genotype. The phenotype is often the end results of those genes, yet is maximum appropriately the outline of a chain of exact attributes or behaviors. utilizing PCR to enhance a gene, and then visualizing the consequent with electrophoresis turns a genotype right into a pcr phenotype.

2016-12-05 09:31:09 · answer #2 · answered by miracle 4 · 0 0

Oh I know this, but I forgot. Its on the tip of my tongue, damn it.There are two parts to this definition ...
Phenotype This is the "outward, physical manifestation" of the organism. These are the physical parts, the sum of the atoms, molecules, macromolecules, cells, structures, metabolism, energy utilization, tissues, organs, reflexes and behaviors; anything that is part of the observable structure, function or behavior of a living organism.
Genotype This is the "internally coded, inheritable information" carried by all living organisms. This stored information is used as a "blueprint" or set of instructions for building and maintaining a living creature. These instructions are found within almost all cells (the "internal" part), they are written in a coded language (the genetic code), they are copied at the time of cell division or reproduction and are passed from one generation to the next ("inheritable"). These instructions are intimately involved with all aspects of the life of a cell or an organism. They control everything from the formation of protein macromolecules, to the regulation of metabolism and synthesis.
The "internally coded, inheritable information", or Genotype, carried by all living organisms, holds the critical instructions that are used and interpreted by the cellular machinary of the cells to produce the "outward, physical manifestation", or Phenotype of the organism.

Thus, all the physical parts, the molecules, macromolecules, cells and other structures, are built and maintained by cells following the instructions give by the genotype. As these physical structures begin to act and interact with one another they can produce larger and more complex phenomena such as metabolism, energy utilization, tissues, organs, reflexes and behaviors; anything that is part of the observable structure, function or behavior of a living organism.
Genotype codes for the phenotype

2007-03-07 11:25:56 · answer #3 · answered by Anonymous · 0 0

A genotype tells what combination of alleles an individual has. Examples of written genotypes are Rr and bb.

A phenotype tell what form of the trait an individual has.
Examples of phenotypes are tall or right-handed.

2007-03-07 11:26:40 · answer #4 · answered by ecolink 7 · 0 0

A phenotype is the physical appearance of the organsim. A genetype is the genetic code of the organism in its DNA that causes the physical appearance. For example, if you have a pea plant and it has the alleles for being short-stemmed, its phenotype will be "short-stem" but its genotype will be "tt" (the two alleles). If the alleles were "TT", the organsim would have a phenotype of "tall stem" and its genotype would be simply "TT".

2007-03-09 06:55:58 · answer #5 · answered by samuelinho_8 1 · 0 0

Phenotype is what you see. In humans, it would be your hair color or blood type.
Genotype is the genetic makeup. We have 2 options for each thing- what our mom or dad gave us. If your mom was blood type A and your dad was O, because A is dominant, your genotype would be heterozygous Ao, but your phenotype would just be type A blood.

2007-03-07 17:18:49 · answer #6 · answered by lafemmesyd 2 · 0 0

a genotype is the genetic makeup of an organism or group of organisms with reference to a single trait, set of traits, or an entire complex of traits while a phenotype is the observable constitution of an organism or in other words the appearance of an organism resulting from the interaction of the genotype and the environment.

2007-03-07 11:28:17 · answer #7 · answered by Johnny M 1 · 0 0

Inside≈genotype
Outside≈phenotype

Sort of.

2007-03-07 11:28:50 · answer #8 · answered by Wonka 5 · 0 0

Introduction:
Corn snake color is comprised of two predominant colors; when combined, they form the brilliant pattern we see in the "normal" corn snake. The two main colours are red and black. Yellow appears in varying degrees and will not be discussed here. The genetics behind the inheritance of color can be viewed as whether or not a snake has both red and black- as in the normal corn, only red as in the amelanistic, only black as in the anerythristic and finally neither which results in the snow corn. There are also factors which dilute or enhance colours, thus resulting in lighter or darker snakes such as okeetees or "ghost" corns but these are more complex and will not be addressed here



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Simple Genetics:
Genes are composed of genetic information (DNA). Different forms of one particlular gene are called alleles. Different alleles of any gene can be either dominant or recessive, depending on whether the trait is expressed when both alleles are present. Whew...what a mouthful. Here's what it boils down to.

Lets consider a gene that encodes an enzyme that makes a black pigment in a make-believe snake. We will represent the normal or wild type allele with the letter capitol "B". A mutation in this gene that prevents its function (it can no longer make the black pigment) is found and will be repesented by small-case "b". Now, the next thing to remember is that animals have two copies of their genes. One set is inherited from their mother and one from the father. So, a wild type (normal) black snake would have normal genes and be represented as "BB". A mutant snake that has no black pigment would be "bb". The mutant has two copies of the defective allele and therefore it is unable to make any black pigment and the snake is white. Two more definitions. Phenotype is what the snake looks like, black or white. Genotype is what alleles it carries, BB or bb.

Now if a wild type black snake (BB) is mated to a mutant white snake (bb) then all of the offspring will have one normal gene from one parent (B) and one mutant gene from the other (b). The offsrping will be "Bb" or heterozygous, meaning having two different alleles at a particlular gene. In this example, the heterozygous offspring will be black because they still have one functional gene (B) and can still make black pigment. So the phenotype for the heterozygous animal is black while its geneotype is Bb. Also, if you catch (or buy) a black snake (phenotype), you have no way of knowing if the geneotype is BB or Bb. However, if the phenotype is white, then you would know the geneotype is bb.

Now this fictional example is actually very close to what occurs in corn snakes except that there are primarily two genes involved, one that encodes the black color seen on the ventral surface and around the edges of the saddles and another gene which encodes the red color of the saddles and ground pattern.



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Corn Snake Genetics
Now let's apply our "mini-lesson" in genetics to the corn snake. As mentioned earlier, they have two main colours responsible for their beautiful coloration. Red and black. A wild type or normal corn snake's genotype, can be represented as "RRBB". The RR refers to the gene for red coloration and BB, the gene for black. [At this point I should admit that I am vastly simplifying things. In reality there are more than two genes involved. However, one can predict the offspring of many cornsnake matings using this simple two gene treatment.] These two traits are not linked in any way, the inheritance of each is separate. Corn snakes that are unable to make black pigment (bb) are refered to as amelanistic. Those unable to make red pigment are known as anerythristic, a real tongue twister. Lastly, cornsnakes that make neither red nor black are called snow corns. Here are some pictures of what these snakes look like (their phenotypes).

Lets consider the mating of a wild type corn snake (RRBB) with a snow corn (rrbb). To analyze the possible outcomes of this cross, you must first determine what types of gametes (sperm and eggs) are possible. A gamete has only ONE set of genes. So the wild type corn can only make one type of gamete, RB, and all its sperm or eggs will have that geneotype. Likewise, the snow corn can only make gametes that have the genotype rb. The offspring will then all have the geneotype RrBb. Their phenotype or colors will all be normal. They will make black because they have one B gene and will also make red because they will all have one R gene as well. They will all be double heterozygous, meaning they have one wild type and one mutant allele at two different genes.

What happens if we cross one double heterozygote with another. First, what are the possible gametes produced from a RrBb snake. There are 4 possiblities: RB, Rb, rB and rb. They are each equally possible, so 25% of the gametes will be RB, 25% Rb, etc etc. To determine the geneotypes and phenotypes of the offspring from this cross, one takes the possible gametes and forms a Punnett Square. Since each snake can form 4 different gametes and since these can each combine randomly, there are 16 different combinations of genotypes for the offspring. These are shown below in the Punnett Square.


RB Rb rB rb
RB RRBB RRBb RrBB RrBb
Rb RRBb RRbb RrBb Rrbb
rB RrBB RrBb rrBB rrBb
rb RrBb Rrbb rrBb rrbb

Next, when you sort through the results, you'll find that you have 9 different geneotypes and 4 different phenotypes in various ratios depending on how frequently they arise in the Punnett Square. The results are shown in the table below.


Frequency
(out of 16) Genotype Phenotype
1 RRBB normal
2 RRBb normal
1 RRbb amelanistic
2 RrBB normal
4 RrBb normal
2 Rrbb amelanistic
1 rrBB anerythristic
2 rrBb anerythristic
1 rrbb snow

When all the phenotypes are totaled, the outcome of this cross is 9 normal, 3 amelanistic, 3 anerythristic and 1 snow.

2007-03-09 16:15:58 · answer #9 · answered by Rajkiya 2 · 0 0

Genotpye- a gene responsible for a phenotype
Phenotype- the physical appearance of someone because of their genotype

2007-03-11 11:51:29 · answer #10 · answered by Hzl 4 · 0 0

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