So why do equal probabilities of survival and reproduction reproduce parental allele frequencies in the offspring generation?
Hopefully the answer to this question is more obvious now that you understand that an equal likelihood of surviving and producing surviving offspring is really about each individual having an equal chance of providing one of the two gametes to every fertilization event that occurs in a population and produces a surviving offspring. Nothing is operating to bias the chances of an individual contributing a gamete to each and every fertilization event and every individual's two alleles have an equal (50:50) chance of ending up in the gamete involved in fertilization. But in case its not quite clear, let's explore the issue a bit further.
To do this, re-examine the pool of potential gametes depicted as buckets in the cartoon above (which is repeated below for your benefit) and answer the questions that follow.
a. If a gamete is randomly selected from this population, as happens when each individual has an equal chance of surviving and reproducing, what is the likelihood (probability) that it contains an
A allele?
b. Explain the reasoning behind your response to question a.
Much as there is a 13 in 20 chance of blindly pulling a gold chip out of a bag of 20 chips of which 13 are gold and 7 blue (and they differ in no other way), there is a 13 in 20 or 65% chance that the gamete would contain an
A allele, if a a gamete were randomly selected from the population above (13/20 = 65/100 = 0.65*100 = 65%). Buckets of
A alleles are nearly twice as common as buckets of
a alleles. Consequently when reproduction is random, as happens when every individual has an equal probability of surviving and reproducing, any randomly selected parent is nearly twice as likely to be carrying an
A allele as opposed to an
a allele.
Now consider the following questions.
a. If 15 random matings took place in this population, requiring a total of 30 gametes to be randomly selected, what is the likelihood that each randomly selected gamete contains an
A allele? How about an
a allele?
b. Explain the reasoning supporting your response to question a.
c. Imagine all 30 of the gametes resulting from 15 random matings displayed on a piece of paper in front of you, how frequently would you expect the
A allele to occur in this collection? The
a allele? Why? Please explain.
d. Review your responses to questions a and c. What do they tell you about how likely (frequently) the
A allele is to appear in the offspring population? The
a allele? Why? Please explain.
Ideally, your responses to questions a and c were identical. For each of the 15 random mating events, the probability that a contributed gamete contains an
A allele is 13/20 (65%) and an
a allele 7/20 (35%). This is true because each gamete selection event is independent; the allele one gamete contains does not in anyway influence what allele the second gamete of a fertilization event will contain if mating is random. (This is not true is mating is not random. Can you provide an example?)
Since the above is true for each individual mating event, the overall allelic composition of the resulting offspring generation will simply reflect the probability associated with picking each allele during each random gamete selection event summed for all 30 events. Therefore, on average 65% of the 30 alleles will be
A and 35%
a in the offspring generation if mating is truly random.
Questions & Answers
Do somebody tell me a best nano engineering book for beginners?
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
In this morden time nanotechnology used in many field .
1-Electronics-manufacturad IC ,RAM,MRAM,solar panel etc
2-Helth and Medical-Nanomedicine,Drug Dilivery for cancer treatment etc
3- Atomobile -MEMS, Coating on car etc.
and may other field for details you can check at Google
Azam
anybody can imagine what will be happen after 100 years from now in nano tech world
Prasenjit
after 100 year this will be not nanotechnology maybe this technology name will be change .
maybe aftet 100 year . we work on electron lable practically about its properties and behaviour by the different instruments
Azam
name doesn't matter , whatever it will be change... I'm taking about effect on circumstances of the microscopic world
Prasenjit
how hard could it be to apply nanotechnology against viral infections such HIV or Ebola?
Damian
silver nanoparticles could handle the job?
Damian
not now but maybe in future only AgNP maybe any other nanomaterials
Azam
Hello
Uday
I'm interested in Nanotube
Uday
this technology will not going on for the long time , so I'm thinking about femtotechnology 10^-15
Prasenjit
can nanotechnology change the direction of the face of the world
At high concentrations (>0.01 M), the relation between absorptivity coefficient and absorbance is no longer linear. This is due to the electrostatic interactions between the quantum dots in close proximity. If the concentration of the solution is high, another effect that is seen is the scattering of light from the large number of quantum dots. This assumption only works at low concentrations of the analyte. Presence of stray light.