Biology Lesson 9: Genetics, Part 2 Flashcards
Structural genes:
responsible for coding outward appearance and inward components of a person’s cells
Regulatory genes:
code for the proteins which turn genes on and off
Mutations:
errors in the genetic code
Translocation:
occurs when broken peices of chromosome attach to the wrong chromosome
Deletion:
occurs when a segment of a chromosome breaks off and is lost
Inversion:
occurs when a segment breaks off and reattaches in the correct place, but inverted- upside down
There can be errors in the genes called
point mutations, these occur when one or more nucleotide in the sequence
Substitution:
occurs when a nucleotide is removed and replaced with a different nucleotide
Addition:
occurs when an extra nucleotide is placed in the sequence causing a frame shift, when all the nucleotides in the DNA are shifted down by one.
Deletion:
occurs when a nucleotide is removed from the DNA causing a frames shift
There can be aneuploidy mutations:
the presence of an abnormal number of chromosomes
2 types of aneuploidy mutations
Trisomy, Monosomy
Trisomy
instead of a homologous pair, there are three chromosomes
Monosomy
instead of a homologous pair, there is just one chromosome
Example of trisomy
Down syndrome
Example of monosomy
turner’s syndrome
Mutations
mutations can account for some of the change we see in a species over time
Microevolution
small changes you see in species over time
Macroevolution
massive changes take place over long periods of time, altering a species into something very different
Eugenics
means good origins
The goal of eugenics is to–
increase the types of people seen as desirable and decrease the populations of people who seen as undesirable
Positive eugenics:
the belief that people with desirable qualities should be breed more to increase desirable traits in the population
Negative eugenics:
the belief that people with undesirable qualities should be breed less or not at all to prevent those traits from being passed to the next generations
Examples of eugenics
The Jewish Holocaust in nazi Germany
Sterilization laws in the U.S.
Modern genetics screen of unborn babies for birth “defects”
Cloning:
genetic duplicates
Genetic engineering:
when genes of an organism are changed through artificial means to alter organism’s phenotype