Transposable elements are considered to be responsible for vast range of genome diversity and gene silencing.
Explanation:
Transposable elements are short sequences of DNA that have the ability to move from one location to another in the genome. During this process they copy themselves.
The entire process carried out by transposable elements to copy themselves and move from one location to another is called transposition.
Transposition may result in mutation and is potentially a major source of genome diversity and change. If a transposon inserts itself into the coding region of a gene,it interrupts the coding sequence and inactivates the gene expression.
In addition to this, a transposable element may contain transcription or translation termination signal that will block the gene expression downstream of insertion site.
One group of reptiles, characterized by the fossil Archaeopteryx, led to the evolution of birds. The correct answer is birds
Apple (fruit): leaf, stalk, mesocarp, seed, endocarp, exocarp. Lily (flower): stamen, style, ovary, ovule, , stigma, petal, receptacle, peduncle, and sepal.
Answer:
Crossing two chickens heterozygous for the trait feather color, when brown feathers are dominant over red feathers, will produce offspring with brown and red feathers in a brown:red phenotypic ratio of 3:1.
Explanation:
Knowing that in chickens brown feathers are the expression of the dominant allele (B) and the recessive allele is red (b), crossing two heterozygous individuals (Bb) will result in offspring that are likely to have brown or red feathers.
The cross can be represented by a Punnett Square:
<u>Bb X Bb cross
</u>
alleles B b
B BB Bb
b Bb bb
Where the result is:
<u>Genotypes</u>:
<u>Phenotypes</u>:
- Brown feathers, 75%
- Red feathers, 25%.
In this case, the probability of having brown or red feathers is 3:1.
Answer:
rr
Explanation:
Alleles that are recessive will be lower case. Alleles that are dominant are upper case. Since we have two recessive alleles represented by 'R', the alleles would be written as 'rr'.
