How do melosis and sexual reproduction (fertilization) produce offspring that differ genetically from the parents?
First off, it is Meiosis, which deals with the reproduction of sex cell- mitosis deals with somatic (body) cells
okay now to your question. Each Parent carries a gene well not one more like 46 (somatic)but in Meiosis only 23. Each gene or Alleles which are traits or copies of that same gene are transfered in meiosis. A Dominant gene is an alleles that is carried more prominantly in the gene, example brown eyes is a dominant gene which is why more people have brown eyes. A Recessive gene is a alleles that is carried less prominantly in the gene (same scenario as the Dominant gene) but for example blue eyes is a recessive gene and that is why there aren't many blue eyed people. Now I'm sure your asking: How do you know what is Dominant and Recessive well a fellow by the name of Reginald Punnett a Pea Plant farmer came up with what is now known today as - you guessed it- the Punnett Square.
This is a simple graphical way to determine all the potential combinations of genotypes in everything living. (He used it to breed healthier taller Pea Plants) A Genotype is the genitic makeup of something or someone AKA Alleles. Im going to give you an easy example.
I have a Recessive gene Red hair.
I will have this as {rr} in the Punnett Square.
My b/f has a Dominant gene Brown hair. I will have this {BB} in the Punnett Sqaure.
Here is the the Punnett Sqaure set-up(imagine this as a grid) Put the genotype of one parent on the side and the other at the top,
[B] [r]
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[B] [ BB ] [ Br ]
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[r] [Br ] [ rr ]
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ok let my explain. [Br] represents that Brown hair is dominant over Red and visa versa. My grid shows that our children have a possibility of 25% completley Dominant [BB] brown hair gene 50% [Br] which shows that brown is dom. over red and 25% Recessive [rr] red hair. It basically shows that 75% of chance is our child will have brown hair and only 25% will have red hair.
Of course there are many possibilities my example shows the most easiest form.
I hope I answered your question; I know it is confusing but if you still don't understand google punnett square and most sites can help you better understand this.
the grid should be set us like this
B r
B BB Br
r Br RR
i don't know why it set up like it did but it should look like this
Melosis and sexual reproduction, specifically fertilization, result in offspring that differ genetically from the parents due to the process of genetic recombination.
In mitosis, which is a form of cellular division, the original cell divides to produce two daughter cells that are genetically identical to each other and to the parent cell. This type of cell division is responsible for growth, repair, and asexual reproduction in many organisms. However, it does not contribute to genetic variation.
On the other hand, sexual reproduction involves two individuals contributing genetic material, resulting in a unique combination of genetic traits in the offspring. This process can be broken down into several steps:
1. Meiosis: This is the specialized form of cell division that produces sex cells, or gametes. It involves two consecutive divisions, resulting in four daughter cells, each containing half the number of chromosomes as the parent cell. This reduction in chromosome number is important for maintaining a stable chromosome number across generations.
2. Genetic Recombination: During meiosis, the chromosomes pair up with their homologous counterpart (one from each parent) and exchange genetic information in a process called crossing over. This mixing of genetic material creates new combinations of genes on the chromosomes, leading to genetic variation.
3. Fertilization: When two gametes (sperm and egg) from different parents unite during fertilization, they combine their genetic material to form a zygote, which develops into a new organism. This combination of genetic material from two different individuals further adds to the genetic diversity of the offspring.
Overall, the process of meiosis, genetic recombination, and fertilization ensures that each offspring inherits a unique combination of genetic traits from their parents, leading to genetic variation and differences from their immediate ancestors.