lessons 5

Purebred

(of an animal) bred from parents of the same breed or variety. noun purebred. She had her heart set on adopting a purebred Siamese kitten. Purebred is defined as an animal or human which is the result of unmixed breeding. An example of purebred is a cat whose parents were both Siamese.

Homozygous

Alternative forms of a given gene are called alleles, and they can be dominant or recessive. When an individual has two of the same allele, whether dominant or recessive, they are homozygous. Heterozygous means having one each of two different alleles.May 26, 2015 Although Jim has one orange and two apples, he needs three oranges to make a homozygous glass of orange juice.

. Genotype

The genotype - a term coined by Danish botanist, plant physiologist and geneticist Wilhelm Johannsen in 1903 - is the part of the genetic makeup of a cell, and therefore of an organism or individual, The genotype is the set of genes in our DNA which is responsible for a particular trait. The phenotype is the physical expression, or characteristics, of that trait. For example, two organisms that have even the minutest difference in their genes are said to have different genotypes.

Trait

a distinguishing quality or characteristic, typically one belonging to a person. Selective breeding (also called artificial selection) is the process by which humans use animal breeding and plant breeding to selectively develop particular phenotypic traits (characteristics) by choosing which typically animal or plant males and females will sexually reproduce and have offspring together.

Meioss

a type of cell division that results in four daughter cells each with half the number of chromosomes of the parent cell, as in the production of gametes and plant spores. Image result for meiosis sentenceslideplayer.com The definition of meiosis is the process of cellular division. An example of meiosis is when a chromosome reduces from a double cell to a single cell.

Multiple alleles

multiple alleles Three or more alternative forms of a gene (alleles) that can occupy the same locus. However, only two of the alleles can be present in a single organism. For example, the ABO system of blood groups is controlled by three alleles, only two of which are present in an individual. "multiple alleles." multiple alleles Three or more alternative forms of a gene (alleles) that can occupy the same locus. However, only two of the alleles can be present in a single organism. For example, the ABO system of blood groups is controlled by three alleles, only two of which are present in an individual

Dominant allele

n an allele that produces the same phenotype whether its paired allele is identical or different. Synonyms: dominant Type of: allele, allelomorph. (genetics) either of a pair (or series) of alternative forms of a gene that can occupy the same locus on a particular chromosome and that control the same character. Usually only one of these, the dominant allele, is expressed in the phenotype. 2. Dominant allele: an allele, which has the same effect on the phenotype of an organism, whether the organism is homozygous or heterozygous for the gene. ... The allele can divide into two different types: dominant allele and recessive allele.Apr 17, 2017

Polygenic inheritance

polygenic inheritance (multifactorial inheritance; quantitative inheritance) The determination of a particular characteristic, e.g. height or skin colour, by many genes (polygenes), each having a small effect individually. Characteristics controlled in this way show continuous variation. "polygenic inheritance." Polygenic inheritance is a non-Mendelian form since it is controlled by multiple genes at different loci on different chromosomes expressed together. In humans, height, weight, and skin color are examples of polygenic inheritance, which does not follow a Mendelian pattern of inheritance.

Fertilization

the action or process of fertilizing an egg, female animal, or plant, involving the fusion of male and female gametes to form a zygote. Fertilization Sentence Examples. Fertilization is effected by the union of two nuclei in all those cases which have been carefully investigated. ... This is a necessary consequence of the fusion of two nuclei in fertilization, unless the chromosomes are to be doubled at each generation.

Probability

the extent to which something is probable; the likelihood of something happening or being the case. What reason was there for assuming any probability of an uprising in the city?

. Phenotype

the set of observable characteristics of an individual resulting from the interaction of its genotype with the environment. the physical appearance of an organism resulting from its genetic makeup and environmental influence

Gene

(in informal use) a unit of heredity that is transferred from a parent to offspring and is held to determine some characteristic of the offspring. gene. The definition of a gene is a unit on a chromosome that determines a specific trait in an organism, or a male's name. An example of a gene is a chromosome unit that determines a person's eye color. An example of a man named Gene is the actor Gene Wilder.

Codominance

Codominance is a form of dominance wherein the alleles of a gene pair in a heterozygote are fully expressed. This results in offspring with a phenotype that is neither dominant nor recessive. A typical example showing codominance is the ABO blood group system.Nov 1, 2016 Example sentences for: codominant. ... The codominant alleles E2, E3, and E4 determine the six APOE genotypes. Suppose the major gene has two different codominant alleles, the posterior probablities in equation (4) can be exactly calculated for a usual mating design.

Incomplete dominance

Incomplete dominance is a form of intermediate inheritance in which one allele for a specific trait is not completely expressed over its paired allele. This results in a third phenotype in which the expressed physical trait is a combination of the phenotypes of both alleles. Examples of Incomplete Dominance. ... Pink roses are often the result of incomplete dominance. When red roses, which contain the dominant red allele, are mated with white roses, which is recessive, the offspring will be heterozygotes and will express a pink phenotype.

. Punnett square

The Punnett square is a diagram that is used to predict an outcome of a particular cross or breeding experiment. It is named after Reginald C. Punnett, who devised the approach. The diagram is used by biologists to determine the probability of an offspring having a particular genotype. The two things a Punnett square can tell you are the genotypes and phenotypes of the offspring. A genotype is the genetic makeup of the organism. This is shown by the three genetic conditions described earlier

Heterozygous

The genetics term heterozygous refers to a pair of genes where one is dominant and one is recessive — they're different. Like all words with the prefix hetero, this has to do with things that are different — specifically genes. ... If you inherited the same gene from both parents, it's homozygous — the same. RhymeZone: Sentences that use heterozygous. This is consistent with a heterozygous or balancing selection coefficient for these loci. If the alleles are different, they and the organism are heterozygous with respect to that gene.

Recessive allele

n an allele that produces its characteristic phenotype only when its paired allele is identical. Synonyms: recessive Type of: allele, allelomorph. (genetics) either of a pair (or series) of alternative forms of a gene that can occupy the same locus on a particular chromosome and that control the same character. allele is identical. (1) A recessive allele must be present in double copy to show itself, and all green peas have two green alleles. ... (3) Recessive allele : an allele, which only shows in dominant allele is present.

Allele

one of two or more alternative forms of a gene that arise by mutation and are found at the same place on a chromosome. The definition of alleles are pairs or series of genes on a chromosome that determine the hereditary characteristics. An example of an allele is the gene that determines hair color.

Hybrid

the offspring of two plants or animals of different species or varieties, such as a mule (a hybrid of a donkey and a horse). Hybrid Sentence Examples. Many hybrid forms of varying shades of colour have been raised of late years. Hybrid plants may be again crossed, or even re-hybridized, so as to produce a progeny of very mixed parentage. A hybrid between the yak and Indian cattle, called zo, is commonly reared in Tibet and the Himalaya.

Heredity

the passing on of physical or mental characteristics genetically from one generation to another. Heredity Sentence Examples. The general laws of heredity and variation have been proved to apply to man as well as to animals and plants. I guess so, but I wonder sometimes if heredity is the major factor. ... It depends on heredity, what you feed them, time of the year and a lot of other factors.

Genetics

the study of heredity and the variation of inherited characteristics. Every living thing contains the genetic material that makes up DNA molecules. This material is passed on when organisms reproduce. The basic unit of heredity is the gene. (See chromosomes; dominant trait; genetic code; Gregor Mendel; recessive trait; and sexual reproduction.)