Genetics: DNA, RNA, and proteins Flashcards
Each chromosome is long, but the DNA is wrapped around proteins that make them
shorter
What is the key to distinguish between transcription and translation in gene expression?
DNA and RNA are both nucleotide, so they have the same language (transcription)
When you move from RNA to amino acids, you need to translate it
When DNA is transcribed into RNA, thymine is replaced into what base?
Uracil
Why do triplets of RNA code each amino acid rather than twins?
There are 21 amino acids in total. Twins would only result in 4^2 = 16 combinations. Triplets allow for expression of each amino acid.
What could a base pair switch mutation cause in terms of protein production?
A protein codon could turn into a stop codon. making an incomplete protein that doesn’t work
Only around __% of the DNA in our chromosomes codes for a gene
3
What are introns? (intragenetic region)
Parts of the DNA that are not part of mRNA.
What are exons? (expressed region)
Any part of the gene that will encode
Where does DNA to RNA transcription occur?
In the nucleus, as you’re not gonna take the chromosome out of it
Hemophilia is an _-linked _________ disorder
X, recessive
What is a sex-linked gene?
Any gene located on a sex chromosome
What affliction is a common human sex-linked disorder caused by a malfunction of light-sensitive cells in the eyes?
Red-green colourblindness
What false conclusion did the scientific community accept for 33 years?
That humans have 48 chromosomes. We now know that there are 46.
What is gene mapping?
Using methods to identify they locus of a gene and the distances between genes
What is a genetic map and what is a physical map?
Genetic maps are based on genetic linkage (recombination) information)
Physical maps use actual physical distances measured in DNA base pairs