Complete question:
Suppose "A" is a dominant gene for the ability to taste phenylthiocarbamide and "a" is a recessive gene for the inability to taste it. Which couples could possibly have both a child who tastes it and a child who does not?
a. father AA, mother aa
b. father Aa, mother AA
c. father Aa, mother Aa
d. father AA, mother AA
Answer:
c. father Aa, mother Aa
Explanation:
According to the given information, the ability to taste phenylthiocarbamide is a dominant trait and is imparted by the allele "A". This phenotype would be expressed in both homozygous and heterozygous conditions. The non-taster phenotype would be expressed in the homozygous recessive genotypes only.
To have both taster and non-taster children, both the parents should have at least one copy of the recessive allele. Among the given options, the father with genotype Aa and the mother with genotype Aa have the possibility to have both taster and non-taster children.
Aa x Aa= 3/4 taster (1/4 AA and 1/2 Aa): 1/4 non-taster (1/4 aa)
Answer and Explanation:
Corals are translucid or white, but they look brightly colored because they host symbionts with colorful photosynthetic pigments
. They can host different organisms that live on and among them, giving place to an amazing ecosystem.
One of these organisms is the photosynthetic unicellular microalgae, called zooxanteles, that are colorful and provide nutrients to the coral.
Corals provide shelter and protection to the algae, while algae provide nitrogenated nutrients, sugars, and color to the corals. Algae can store nitrogen in their tissues as nitrogen-rich crystals, which are constantly provided to corals.
This symbiotic relation allows corals to grow in different environments that are poor in nitrogen or other nutrients, such as the tropical clear waters.
When changes in radiation, temperature, or salinity in water occur, corals react to these changes losing these algae and becoming translucid again.
The part of the root that contains transport tubes is the root hair. The primary role of the root hair is to absorb water and nutrients from the soil. They are hair-like and tubular in structure and are sometimes rarely visible by the naked eye.