This blog post will basically
touch the simple facts, the history of genetics, etc.
1886: Gregor Mendel discovered that traits of offspring depend on the parents traits, which may be dominant or recessive. ( but this was somehow lost)
1902: Theodore Boveri & Walter Sutton used color to observe chromosomes
1905: Nettle Stevens found out that all homologous chromosomes are the same except the ones that determines sex (X,Y)
1909: Thomas H Morgan made many important researches in fly genetics and linked analysis that apply to all diploid organisms
1941: Beadle and Tatum discovered that each gene encodes one protein
1944: Oswald Avery identified DNA as genetic material
1953: Rosalind Franklin and Maurice Wilkins showed that the DNA is a double helix, Thomas Watson and Frances Crick figured out that the base of the double helix enabled replication
1970: Tamin and Baltimore found a enzyme used to clone genes
1981: First transgenic mammals are made
Genetics is the features
and characteristics that make up an organism.
1996: Iam Wilmut cloned the lamb Dolly from adult mammary gland tissue
decipher what you will look like, and your features.
There are many things you can learn about your genetics
like your DNA and what factors are inside of it to make it important, also your
genotype/phenotype, and what a recessive gene and dominant gene is.
Lets start simple:
DNA stands for Deoxyribonucleic
acid. Your DNA is a molecule that carries all of your genetic information
Genotype describes what certain alleles are on a certain
Alleles are a form of a gene that play part on a specific
chromosome, which controls a certain trait.
There are dominant and recessive alleles
Dominant alleles are upper case and usually the trait that
comes out the most
Recessive is usually shown with an lower case letter, and
in this allele it is usually the trait that does not show unless the organism
Homozygous just means that both of the alleles are either
dominant or recessive
Heterozygous means that one of the alleles are dominant and
one is recessive
Phenotype is the physical characteristics of the gene
There are many ways that you can determine what exactly an
offspring’s traits will be by using genotype. One way is to look at the alleles
of the two organisms. Also if you really wanted to be accurate you will put
them in a punnet square.
squares is just a fancy word to describe the separation of alleles to figure
out what an offspring may look like, also to fish out the chances of having a
example a mother and father are about to have a child they want a child with blue
eyes. The mother has two alleles bb, which are homozygous. The father also has
two alleles Gb, which are heterozygous. Knowing that the father has green eyes,
because greens allele is dominant and blue is recessive you can figure out what
is the chance of the child having blue eyes.
looking at this you can see that the child has a 50% chance of having green
eyes or having blue eyes. But what if the father was also homozygous? There would be no chance at the child being born with blue eyes.
the PSSA I do not know exactly what kind of questions will be asked, but make
sure you do the study island and also look up a few things to make sure you
understand such as:
your DNA gets its information from and what it is made up of and how its held
many chromosomes a human has (46)
types of gene disorders and also different types oh names for each type of gene
kind of diseases are gene orientated