My biology teacher said that one white and one black parent having a child is not blending.?

Question

I don't understand though. All babies from one black and one white parent I have seen are a light brown color. I have never seen a white baby from one black parent. So why is it not blending? She said the Blending Theory used to be believed, but was disproved.

Answer 1

I guess it followed the Mendel's theory for segregation.  Maybe the "black-colored-skin" trait is a recessive trait while "light-colored-skin" is the dominant one.  

On my knowledge "curly-hair" is dominant trait, so when a curly-haired person paired with straight-haired person, the children will have curly- or wavy-hair.

Please check any Mendel-related reference, I think it would help.

Answer 2

Well there was an interracial couple who had twins where they had different colored skin tones.  I guess it was disproved because genetics can sometimes skip a generation and such. Here's a photo of the family below.

http://www.thestencil.com/archives/image...

Answer 3

Having just read what the 'blending theory' is I would concur.  It would appear that blending - in the sense that the child of two parents is an 'average of the two' is a very unscientific theory that is disproved every time a child is born.

Example - I have brown eyes and my boyfriend has brown eyes.  So going on the blending theory our daughter should have brown eyes, but her eyes are bright blue.  

Blending in the sense of a mix of genes would be a correct description of any child, but to use the 'blending theory' is incorrect.

Answer 4

A specific characteristic of an individual is determined by presence or absence of a particular genetic  character. Thus absence of melanin pigment is white colour of skin and high amount of melanin is black colour.

In blending we expect that black & white [colours] can be mixed to produce different sheds of gray or more so blue and yellow [colours] mixed, can be green. This does not happen in genetics. If baby gets genetic makeup for low melanin she is white; and if for high melanin she is black. genes do not blend. So in fowers let us say if blue is dominant over yellow, then absence of blue will be yellow. 2 genes of blue will be blue, and a combination of one blue and one yellow gene will also be blue.

Dr. Abhay

Answer 5

Okay: there is a lot of misinformation in many of the answers so far. Many traits, such as skin color are controlled by many genes interacting and, in the short term give the appearance of blending.

Blending theory works on the  idea that offspring should show an appearance mid-way between the two parents in the same  way mixing two paints produces a new in-between color: for example, mixing blue and yellow will produce green. In this case, if you mate two of the green offspring, all they can produce is green, since blending says the children will be the blend of two identical colors.

By contrast, the Mendelian approach states that traits are due to the inheritance of 'particles' termed genes so, rather than mixing paint think mixing marbles. In the above case one parent passes on many blue marbles, the other many yellow. When you look at this from a distance, it looks green. When two of these individuals mate they will each pass on a random mix of blue and yellow. Most of the time the offspring will get a mix and be some shade of green. However, in a few cases it will happen that both parents pass on all blue, or all yellow and the offspring will look like the grandparents. An example of this in humans can be seen when two parents are both mixed race and can occasionally  produce children at either end of the color spectrum

p://www.dailymail.co.uk/news/article-3...

Answer 6

It would be the blending of genetic traits, but not blending of colours/pigments.

Example: One parent with blue eyes and one parent with brown eyes will only produce blue or brown eyed children, not browny-blue eyes.  

The lightening of skin pigment in the children would be due to a mixture of genes controlling melanin production.