Symbiosis in lichens is the mutually helpful symbiotic relationship of greenalgae and/or blue-green algae(cyanobacteria) living among filaments of a fungus, forming lichen. The algaeor cyanobacteria benefit their fungalpartner by producing organic carbon compounds through photosynthesis
which is more likely to be the cause of down syndrome the egg or the sperm?
The egg
Answer:
25%
Explanation:
When looking at a pedigree remember that:
- squares are males
- circles are females
- the solid colored figure represents an individual affected by a disease
- the empty figure represents a healthy individual
Let us assign the symbol X⁺ to represent the dominant allele linked to the X-chromosome and expressing healthiness, and X⁻ to represent the recessive allele expressing the dissease.
According to this pedigree
- I1 is a man affected by the disease, YX⁻
- I2 is a healthy woman X⁺X⁻
- we can see that among the progeny (generation II) there are two individuals affected (a boy and a girl) and one healthy girl. This means that the mother I2 is heterozygous for the trait.
So, having their genotypes we can know what are the probabilities of getting a son with DMD
Parentals) YX⁻ x X⁺X⁻
Gametes) Y X⁻ X⁺ X⁻
Punnett square)
X⁺ X⁻
X⁻ X⁺X⁻ X⁻X⁻
Y X⁺Y X⁻Y
F1)
- The probabilities of getting a healthy daughter X⁺X⁻ are 25%
- The probabilities of getting a healthy son X⁺Y are 25%
- The probabilities of getting a daughter with DMD X⁻X⁻ are 25%
- The probabilities of getting a son with DMD X⁻Y are 25%
Because plants go through a cycle(the cycle is seed, seedling, plant, flower and tree.) and it takes time for the plant food, water, and nutrients to go though the plant.
Answer:
Same phenotype but different genotype is possible due to presence of dominant allele
Explanation:
A person can have a dominant allele on both the homologous chromosomes while another person may have single dominant allele and a corresponding recessive allele.
