What is considered a dominant allele?
A dominant allele is a variation of a gene that will produce a certain phenotype, even in the presence of other alleles. A dominant allele typically encodes for a functioning protein. … When a dominant allele is completely dominant over another allele, the other allele is known as recessive.
What does TT allele mean?
The notation Tt means the heterozygous condition, wherein the homologous pair contains different alleles of a gene. … ‘Tt’ refers to the heterozygous condition with a dominant and a recessive allele and tallness being the dominant trait, it is expressed in the phenotype.
What is the phenotype of TT?
The phenotype of a plant with the genotype Tt would be tall. Here tallness (T) is a dominant trait over dwarfness (t), which is recessive. Tallness and dwarfness (stem height) are one of the seven contrasting pairs of traits in pea plants studied by Mendel.
Is TT a hybrid genotype?
If the two alleles are the same (TT or tt), the genotype is considered purebred. If the two alleles are different (Tt), the genotype is considered hybrid. This example shows the inheritance of a single characteristic (height). A cross that shows the inheritance of a single characteristic is known as a monohybrid cross.
What does tt mean on a Punnett square?
Explanation: In a Punnett square, lower case letters are recessive alleles and upper case letters are dominant alleles. So, “tt” would mean that both alleles are recessive. In comparison, “Tt” would mean that one allele is dominant and one is recessive.
What are the 3 types of dominance?
There are different types of dominance: incomplete dominance, co-dominance and complete dominance.
What is a dominant allele Class 12?
– Dominance, in genetics, has a greater effect on one of the pairs of genes (alleles) that affect the same inherited character. If the individual pea plant with alleles T and t (T = height, t = shortness) is the same height as the individual TT, the T allele (and the height trait) is said to be fully dominant.
What is an example of a recessive allele?
Examples of Recessive Traits
For example, having a straight hairline is recessive, while having a widow’s peak (a V-shaped hairline near the forehead) is dominant. Cleft chin, dimples, and freckles are similar examples; individuals with recessive alleles for a cleft chin, dimples, or freckles do not have these traits.
How are the plant height genotypes TT and TT similar?
Tallness is the recessive trait for plant height; therefore, the genotypes with Tt and TT would have the same phenotype. … Tallness is a recessive trait in pea plants. C. Tallness is the dominant trait for plant height; therefore, the genotypes with Tt and TT would have the same phenotype.
What is dominant in Punnett Square?
E.g. Tall or short. ▪ Dominant trait: Signified by capital letter-E.g. T. If the traits you are using are dominant or recessive, this. trait will “overpower” the recessive trait and will be expressed.
Is GG homozygous or heterozygous?
The true-breeding parents GG and gg are homozygous for the pod color gene. Organisms that have two different alleles for a gene are called heterozygous (Gg). The offspring of the cross between the GG (homozygous dominant) and gg (homozygous recessive) plants are all heterozygous for the pod color gene.
Is TT purebred?
The result of this cross was all tall hybrid pea plants (Tt). When these second-generation plants were crossed, the result was one tall (TT) purebred; two tall (Tt) hybrids; and one short (tt) purebred. Mendel concluded that tallness in pea plants was dominant, and became the expressed trait, (uppercaseT).
What are the gamete possibilities of an organism with the genotype TT?
The parent with the genotype Tt has two different alleles, and half of its gametes will have the T allele, and half will have the t allele. So in regard to the Tt genotype, the parent organism will produce two different types of gametes, T and t .
Is AA a dominant allele?
A dominant allele is denoted by a capital letter (A versus a). Since each parent provides one allele, the possible combinations are: AA, Aa, and aa. Offspring whose genotype is either AA or Aa will have the dominant trait expressed phenotypically, while aa individuals express the recessive trait.