Genetics Flashcards
For a long time, genetics was a very ____ field.
Stagnant.
Explain the sequence of genetics.
Gene (Genotype), mRNA, microRNA, protein, measurable trait or change within an animal. (Phenotype)
Define a gene
Sequence of DNA that direct protein synthesis in a very specific manner. These proteins then influence how traits develop.
What is mRNA?
Messenger RNA. Template which directs assembly of amino acids into proteins.
What is MicroRNA?
RNA template that can block or disrupt protein production.
Genotype?
The number and types of genes an animal possess (Genetic composition)
What is phenotype?
The characteristics of an animal that can be seen or measured (Outward appearance or behavior trait)
What is genomics?
Study of the genetic composition of animals.
What is epidenetics?
Heritable changes in gene expression that do not involve changes in DNA.
What is proteomics?
Study of Proteins that are produced by a specific genome (Or set of genes)
There are two animals. One can tolerate high ambient temperatures, one cant. Describe the phenotype differnce.
Heat tolerance.
In a phenotypic difference, what can be the four possible causes?
Genomic
Epigenetic
Proteonomic
Combination of all of the above.
If a phenotype difference is caused by a genomic difference, what does that mean? Look like?
Different genes cause the different phenotype!
Could be different forms of the same gene (allele difference)
Could be a different association among several genes.
If a phenotype difference is caused by a epidenetic difference, what does this look like? Mean?
Same genes, but certain ones are turned off or on.
DNA methylation patterns turn off a gene. The structure is exactly the same.
If a phenotype difference is caused by a Proteonomic differences, what does this mean? Look like?
The genes are the same, the same genes are turned on and off in each other, but the amount of protein produced is different!!
These are translational differences!! The genetics are exactly the same, but how much the gene is expressed depends on the proteins produced.
If a phenotype difference is caused by an all of the above?
The animals may have different alleles, an epigenetic change turning a gene off, and a protein difference changing the expression.
Things get complicated!
What is something intresting aboout sperm that can make reproductive difficulties hard to figure out?
If you look at sperm under a microscope, it may look completly functional but still not work.
Often this is from the seminal vessels not properly producing protein.
To understand an animals phenotype, we need to understand that:
Both the genetics and the environment of the animal contribute.
What is the basic equation of genetics?
Genotype + environment = phenotype.
What is Heritablity?
The proportion of variation or phenotypic differences among animals that is due to differences or variation in genotype.
What is heritability simplier?
A mathematical ratio! How much do genes contribute to a phenotype versus enviroment.
What does it mean if a trait is 100% heritable? Examples?
Environment has no effect on phenotype?
Ex: Eye color, coat color.
What is complete dominance?
The dominant gene completely masks the recessive.
There are only two phenotypes, and homozygous dominant (BB) is the same as heterozygous (Bb)
In complete dominace, what do the genes look like?
One loci, two forms of the gene (Alleles)
In complete dominace, is the dominate gene always the goal?
NO! sometimes recessive is more healthy. In this case, we select against dominant.
Describe partial dominance.
One loci, two difference forms of the gene.
Now there is a middle ground between dominant and recessive!