Transcript for:
Understanding Heredity and Genetic Variation

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and hairland was derived from her mother therefore the sum of the genetic characteristics of the parents are passed to the child inheritance on the other hand is the acquisition or reception of genetic quality's appearance to offspring in sexual reproduction the genetic materials of two parents is combined and passed on to one individual although the offspring receives a combination of genetic material from the two parents certain genes from each parent will dominate the expression of different traits looking back at this picture the child inherited the characteristics of the nose eyes hair color and skin complexion from her father while she inherited the characteristics of the mother's lips hair lent and freckles genetic variation refers to the differences between individual or the differences between populations it is a state of having different traits and characteristics for example some people are blue eyes some are brown while others have green eyes it is due to the presence of differences in sequences of genes between individual organisms of a species here are some of the genetic terms for your genetic vocabulary enrichment first is the phenotype the term phenotype refers to the observable physical properties of an organism this includes the organism's appearance development and behavior examples pointed nose blue eyes straight hair those are some of the characteristics that we may observe in a human therefore it is the phenotype genotype a genotype is an organism's complete set of heritable genes or genes that can be passed down from parents to upspring genes are primarily represented by pair of letters four examples capital n m is the genotype of a person with a pointed nose capital b small b is the genotype of a person with a blue eyes while capital s s is the genotype of a person with a straight hair genotype can also refer to the two alleles inherited from a particular gene but what are alleles alleles are any of the alternative forms of gene in a genotype it is represented by a letter examples capital n and n are the alleles for pointed nose capital b and small b are the alleles for blue eyes capital s and s are the alleles for straight hair as you can observe there are capital and small letters representation it is because some of the genetic characteristics are dominant while others are recessive dominant rates are inherited characteristics that appear in an offspring if it is contributed from a parent through a dominant allele it is represented by a capital letter alleles for example in this picture you can see that the child inherited the eye color the dimple and the skin color of his mother therefore those characteristics from the mother are dominant on the father while the child inherited the broad lips and the curly golden hair from his father therefore those are the dominant characteristics he gets from his father to represent dominant traits let us use capital b b for brown eyes capital d d for dimple and capital l l for broad lips capital s s for brown skin as you can see the genes are written by capital letters to represent dominant rates on the other hand recessive traits are the weak unexpressed rate of pair of alleles that has no effect in the phenotype of the heterozygous individual going back to this picture the father's blue eyes having not dimpled and his skin color are recessive treats since it is not expressed or observed in the appearance of the child same as the mother's lips and hair which are not observable in the child therefore those are recessive drinks recessive traits are represented by small letter for examples blue ice being a recessive trait can be represented by small bb having nothing pulled for small d d small ll for thin lips and small ss for white skin as you could see those recessive traits are represented by small letters here are some other examples of the dominant and recessive trait representations always remember that the dominant rate has capital letter either both letters are capital or one is capital and the other paired letter is not capital while resuscitates always have small letters but why some traits have the same latter representations of being capital or small while some traits have the combination of both capital and small letter those are what we called homozygous and heterozygous traits a homozygous trait is made up of two same alleles examples capital a a capital f f smaller gg and small ii a heterozygous tree is made up of two different alleles examples capital a is small letter a capital f small f capital g is small g and capital i is small i it is made up of combinations of letters of capital and small letters in these examples you can see homozygous dominant and heterozygous dominant e e for detached heirloom while the homozygous recessive e e is having attached earlobes to test if you learned something on this video let us try to answer this one in a family the father has a tall height characteristics while the mother is short the child possesses the high characteristics of the father the mother's trait is an example of a blank is it a a dominant trait or a b a recessive feel free to comment down below your answer and let us find out if it is correct and that's it with our lesson for today do not forget to subscribe like and share this video see you again on the next lesson