What is a disappearing trait?
In biology, an atavism is a modification of a biological structure whereby an ancestral genetic trait reappears after having been lost through evolutionary change in previous generations.
What are traits that hide other traits?
Alleles produce phenotypes (or physical versions of a trait) that are either dominant or recessive. The dominance or recessivity associated with a particular allele is the result of masking, by which a dominant phenotype hides a recessive phenotype.
What kind of traits seem to disappear in the first generation?
He found that in the first generation of offspring (F1), one trait was expressed in all offspring and one trait completely disappeared. Mendel termed the traits that always appeared in the F1 generation dominant traits because they masked, or dominated, the traits that did not show up at all.
How might a trait disappear for a generation and then reappear in the following generation?
Explain why a trait might seem to “disappear” for a generation, and then “reappear” in the following generation. Recessive traits disappear because 2 recessive alleles are needed to produce the recessive phenotype. They can skip generations and can reappear if an individual inherits 2 copies of recessive gene.
What is an unfavorable trait?
Certain traits are unfavorable and should not be in the population, this includes: down syndrome, other non-multifactorial forms of mental retardation, other chromosomal abnormalities, and single-allele genetic defects. Chromosomal abnormalities occur due to nondisjunction.
What is a beneficial trait?
Beneficial traits are extremely varied and may include anything from protective coloration, to the ability to utilize a new food source, to a change in size or shape that might be useful in a particular environment.
What are the 7 traits that Mendel experimented?
On the next screen, he reveals that there are seven different traits:
- Pea shape (round or wrinkled)
- Pea color (green or yellow)
- Pod shape (constricted or inflated)
- Pod color (green or yellow)
- Flower color (purple or white)
- Plant size (tall or dwarf)
- Position of flowers (axial or terminal)
What is a gene that is always expressed?
dominant gene. a gene that is always expressed, that is directly detectable in the individual.
When a trait demonstrates codominance what happens?
Codominance, in genetics, phenomenon in which two alleles (different versions of the same gene) are expressed to an equal degree within an organism. As a result, traits associated with each allele are displayed simultaneously. An example of codominance is seen in the MN blood group system of humans.
What factors influence your traits?
While the influence of genetics and the environment is usually proposed as a dichotomy, the reality is that genetics and the environment often interact to produce traits. Environmental factors turn genes on or off or change the function of the encoded proteins and enzymes.
What is a non adaptive trait?
a trait that has no specific value with respect to natural selection, being neither useful nor harmful for reproductive success. In human beings, eye color, earlobe size, and the ability to curl one’s tongue are nonadaptive traits.
What is an example of an adaptive trait?
A genetic trait that helps an organism to maximize its reproductive success. For example, in hummingbirds, a long bill can be an adaptive trait since it is both heritable and adaptive.
Which of the following is a dominant trait?
Freckles, cleft chin and dimples are all examples of a dominant trait. Having almond-shaped eyes is a dominant trait whereas having round eyes is a feature controlled by recessive alleles. The trait of detached earlobes, as opposed to attached earlobes, is dominant.
Which is an example of an inherited trait?
Inherited traits include things such as hair color, eye color, muscle structure, bone structure, and even features like the shape of a nose. Inheritable traits are traits that get passed down from generation to the next generation. This might include things like passing red hair down in a family.
Is a trait that is always expressed or shown?
Introduction to Genetics Vocabulary
A B dominant Particular form of a trait that is always expressed. recessive Form of a trait only expressed when paired with the same form. genotype Genetic makeup phenotype Physical makeup
