How are genetic traits passed down through generations?
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Each person has 2 versions of a gene. One will come from their mother and one from their father. This happens when their sex cells split at random and the genes are joined. Genes that have been passed on determine your traits, the colour of your hair, your eyes, how tall you are e.t.c. For example, if a mother has a gene for blonde hair and a gene for red hair and father has two genes for red hair, then the child will have 1 gene for red hair no matter what combination of genes are given by the parents. If an organism has two genes the same (two dominant or two recessive genes) this is called homozygous. If there are 2 different genes (one dominant and one recessive) this is called heterozygous.
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This is a picture of a girl with red hair, she will have two genes for red hair.
http://hairstyles.thehairstyler.com/hairstyle_views/front_view_images/6333/original/002_Sheer-Professionals-Salon.jpg
The next image is of two girls, this shows how some peoples genes make them taller, or shorter.
http://www.englishexercises.org/makeagame/my_documents/my_pictures/2013/apr/E5C_titolo.jpg
The last image has different eye colours, resulting from different genetic combinations
http://youqueen.com/wp-content/uploads/2013/07/eyes-colors.jpg
The next image is of two girls, this shows how some peoples genes make them taller, or shorter.
http://www.englishexercises.org/makeagame/my_documents/my_pictures/2013/apr/E5C_titolo.jpg
The last image has different eye colours, resulting from different genetic combinations
http://youqueen.com/wp-content/uploads/2013/07/eyes-colors.jpg
Describe how the alleles of plants or animals can be selected by humans.
Humans select organisms with particular alleles and breed them with other organisms to create an offspring with the desired characteristics. This is done using a test cross. In this image, one of the parents has BB genes when the other has bb. As you can see, the only possible outcomes are Bb. This means that because the B is dominant, they will have the same phenotype as the parent whose genes are BB.
Describe the process of In Vitro Fertilisation as part of the selective breeding process
There are 5 steps that are used during In Vitro Fertilisation (IVF) there are 5 steps that are used.
Straight away we have changed the natural breeding process. In step one medication has been used to stimulate and develop eggs that wouldn't necessarily be healthy enough to produce a baby. In step two, the human bodies natural selection of the egg being chosen is overridden as the eggs taken are only the biggest and strongest that the doctors choose, and not the choice of the female’s body. Step three, where the sperm is being collected, they again only choose the strongest and fastest specimens. In Step four, an artificially created environment is free of all the natural challenges, such as climate, women's health, stress, knocks and falls, alcohol and food that would impact the embryo in a natural situation. The selective breeding process is most active in the fifth stage where external doctors can choose what they think are the most successful embryos and then transfer only those into the uterus, discarding those with undesired qualities, like genetic defects.
- Scientists or doctors will monitor and stimulate the development of healthy eggs in the ovaries.
- They will then harvest the eggs.
- Then collect the sperm.
- They combine the eggs and sperm together in a laboratory and provide the appropriate environment for fertilisation and early embryo growth.
- Transfer embryos into the uterus.
Straight away we have changed the natural breeding process. In step one medication has been used to stimulate and develop eggs that wouldn't necessarily be healthy enough to produce a baby. In step two, the human bodies natural selection of the egg being chosen is overridden as the eggs taken are only the biggest and strongest that the doctors choose, and not the choice of the female’s body. Step three, where the sperm is being collected, they again only choose the strongest and fastest specimens. In Step four, an artificially created environment is free of all the natural challenges, such as climate, women's health, stress, knocks and falls, alcohol and food that would impact the embryo in a natural situation. The selective breeding process is most active in the fifth stage where external doctors can choose what they think are the most successful embryos and then transfer only those into the uterus, discarding those with undesired qualities, like genetic defects.