Explain the meaning of diffusion?

Answer:

1. A yellow lizard population living on an island with no predators
2. A hawk was introduced to the habitat and starts preying on the yellow lizard because it is easier to see from the air
3. Some of the lizards mutate their color from yellow to greyish brown so they can camouflage
4. Yellow individuals keep being hunted, while brown individuals get to survive
5. The following generations of lizards will have a higher proportion of greyish brown individuals and just a few yellow individuals.  
6. Eventually, almost all of the lizards will be greyish brown individuals.

Explanation:

The scenario is the following.

A population of yellow lizards lives on an island where there is no natural predator. Males of the species use the yellow color to attract females in reproductive seasons. The brighter the males are, the better their genetic quality is. Females are also yellow, but not as bright as males.

A new hawk species was introduced into the island to control some farm pests. But this hawk species prefer to feed on the lizards. The yellow color of these animals contrasts with the dark background and can be easily seen from the air. So the lizard population suffers from significant predation affecting its size sharply.

Some of the lizards then suffer from a mutation and change their color from yellow to greyish brown, which turns to be better to camouflage on the rocks and get to survive. Individuals with greyish brown color get to reproduce at a higher rate than yellow individuals, who keep being hunted by the hawk.

Eventually, after many generations, the yellow individuals decrease to near zero in the population, while greyish brown individuals increase significantly, with males still being brighter than females.

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Natural selection is an evolutive force that can act favoring an allele or against it, according to how it affects the fitness of individuals. Natural selection selects beneficial alleles and increases their frequency in the population.

When many organisms in a population sharing the same trait die, it is because they did not have good fitness, so they were not adapted to the environment and its pressures. The alleles coding for that trait were not good for the fitness of the animals, so they do not get to survive.

These individuals die before reproducing, so they could not transfer their genetic charge to the following generation. Eventually, the alleles coding for the trait will decrease in the population, probably near zero. Natural selection is acting against this phenotype. Other alleles will be beneficiated, and their frequency in the population will increase.

This change in alleles frequency is what we call adaptation.

Natural selection results in adaptation, which means the increase of the aptitude phenotype. Aptitude is the contribution of each genotype to the next generation.

In many cases, adaptations can be correlated to environmental factors or selective pressures applied by other organisms or habitats.

Let us remember that a mutation is a change or alteration in DNI sequences that introduce new variants. Many of these are eliminated, but some of them might succeed and be incorporated into each individual. These mutations are the ones that have been selected by natural selection.  

So, in the exposed example, we are focussing on the lizards population.    

• The selective pressure or modeling environmental factor is predation by the introduced hawk.  

• The lizards´ response to predation is the survival of only those that carry mutations ⇒ greyish brown color  

• Natural selection benefits these mutations.    

• Greyish brown lizards survive and increase their fitness.

Answer:

The genotype of a fly can be determined gray bodied is dominant over black body flies. The possible genotype of a fly is either YY or Yy.

Explanation:

The genotype of a gray bodied fly can be determined with the help of punnett square. The gray bodied fly is crossed with black bodied fly, the original genotype of the fly can be determined. This type of cross is known as test cross.

If the cross results in the formation of all gray bodied progeny, the fly is homozygous dominant with the genotype YY. The cross results in  the mixture of progeny with gray and black body , then the genotype of a fly is heterozygous dominant Yy.

Thus, the genotype of a fly can be determined by the test cross. The fly may have genotype either YY or Yy.

Answer:

Listening. One of the most important aspects of effective communication is being a good listener. ...

Non-Verbal Communication. ...

Be Clear and Be Concise. ...

Explanation:

Answer:

There will be no movement of kinesin motor protein along the microtubules .

Explanation:

Microtubules is an important component of cytoskeleton which play an important role in maintaining cell shape,cell motility,cell division regulation etc.

  Whereas kinesin belongs to the family of motor proteins present in the eukaryotic cell.Kinesin plays an important role axonal transport.

  The hydrolysis of ATP generates energy to power up the movement of kinesin along the microtubules.

 According to the given question if kinesin and microtubules were incubated with an non hydrolyzable ATP analog instead of ATP,then the movement of kinesin along the microtubules will not occur due to lack of energy because the non-hydrolyzable analog of ATP cannot undergo hydrolysis to release energy.

Answer:

C

Explanation: