Answer:
The next generation average time to flowering will be 98 days.
Explanation:
Before answering the question, we need to know a few concepts.
- Artificial selection is the selecting practice of a specific group of organisms in a population -that carry the traits of interest- to be the parents of the following generations.
- Parental individuals carrying phenotypic values of interest are selected from the whole population. These parents interbreed, and a new generation is produced.
- The selection differential, SD, is the difference between the mean value of the trait in the population (X₀) and the mean value of the parents, (Xs). So,
SD = Xs - X₀
- Heritability in the narrow-sense, h², is the genetic component measure to which additive genetic variance contributes. The heritability might be used to determine how the population will respond to the selection done, R.
h² = R/SD
- The response to selection (R) refers to the metric value gained or lost from the cross between the selected parents. R can be calculated by multiplying the heritability h², with the selection differential, SD.
R = h²SD
R also equals the difference between the new generation phenotypic value (X₁) and the original population phenotypic value (X₀),
R = X₀ - X₁
-------------------------------------------------------------------------------------------------------------
Now that we know these concepts and how to calculate them, we can solve the proposed problem.
<u>Available data: </u>
- trying to decrease the maturation time in a population of sunflowers.
- the population mean time to flower is 100 days → X₀
- Chosen parental Plants mean flowering time is 90 days → Xs
- the narrow-sense heritability for flowering time is 0.2 → h²
According to what we sow previously, we need to find out the value of X₁, which reflects the next generation average time to flowering.
- We know that R = X₁ - X₀, so we need to clear this formula to calculate X₁
X₁ = R + X₀
We already know that X₀ = 100 days,
Now we need to calculate R.
We know that h² = 0.2,
Now we need to calculate SD
Xs = 90 days → Parentals media flowering time
X₀ = 100 → Population media flowering time
SD = Xs - X₀
SD = 90 - 100
SD = - 10 days
Knowing this, we can calculate R
o h² = 0.2
o SD = - 10
R = 0.2 x (-10)
R = - 2
- Finally, once we know the R-value we can calculate the X₁ value
X₁ = R + X₀
X₁ = - 2 + 100
X₁ = 98
Physician recommends radiation therapy because radiation therapy helps in preventing cellular growth. It uses high-energy radiation to shrink tumor or kill cancer cells. It may be used to cure or to control malignancy when the tumor can no longer be removed or when lymph node involvement is present; also, it can be used prophylactically to prevent spread. Radiation therapy kills cancer cells by damaging their DNA which is the molecules inside cells that carry genetic information and pass it from generation to generation. Radiation therapy can either damage DNA directly or create charged particles within the cells that can in turn damage the DNA. Cancer cells whose DNA is damaged beyond repair stop dividing or die and when these cells die, they are eliminated by the body through natural process.
Answer:
One key way by which species evolve over time in response to changes in environmental conditions is adaptation by natural selection acting over generations. Characteristics that aid in effective survival and reproduction in the new environment grow more prevalent, while those that do not become less prevalent.
Explanation:
Rodolf Virchow was the scientist that studied how wounds heal and proposed that cells come from preexisting cells. Rodolf Virchow was born on 13th of October in the year 1821 and died on 5th of September in the year 1902.He was a German doctor, pathologist, anthropologist, writer, editor and politician. he was a multi faceted person. He became famous because of his discoveries regarding public health. He is also regarded as the Father of modern pathology. He was German by birth. Although he failed in containing the typhus epidemic that occurred in Upper Silesia but his report was valuable in laying the foundation for public health in Germany.
Answer:
the sun, jupiter, saturn, uranus, neptune
Explanation:
