Genetics Chapter 1 & 2 Flashcards
Genetics
Study of inheritance - How things were inherited
Phenotypes
Observed Traits
Molecular TRANSMISSION of Hereditary Material
(DNA,GENOTYPE)
Molecular EXPRESSION of Hereditary Material
(RNA, Proteins)
Locus / Loci
Chunk of DNA with function
Gene
A stretch of DNA that encodes
What is DNA
DNA is a linear polymer (repeated units) of nucleotides.
A nucleotide is composed of
- Phosphate Group
- Deoxyribose Sugar (5 Carbon Sugar)
- Nitrogenous Space ( Adenine, Cytosine, Guanine, Thymine)
Describe DNA structure
DNA strands are ANTI parallel (Double helix)
Two paired DNA strands are complimentary
Reverse complements - A,T & C,G
DNA strands have polarity: 5’ and 3’ ends
Outside is very water soluble, inside is water repellent - Nitrogen bases are inward, and sugar phosphate is outward
Genetic information is stored in the sequence of nucleotide in DNA
DNA is contained in chromosomes (which also has a protein)
What is a genome ?
Total DNA of an organism
- Genes are coded information for building proteins or building RNA
DNA Splicing
When DNA is transcribed into RNA it needs to remove introns
Introns get cut out bc they intervene
Introns are way larger than exons
Exons are left because they are protein-coding regions
When the protein regions are being created that called translation
Central Dogma of Molecular Biology
- DNA transcribed into mRNA, Translated into protein
- mRNA is a compliment of DNA but protein is a diff language
What is the RNA start Codon ?
AUG (it can never be right at the start)
What are the parts of a protein
- Amino Group
- Side chain 1 (can change AND UNQIUE to every amino acid)
- Carboxyl Group (COOH)
Describe RNA strands
- Single strands that are complementary to DNA strand
Who first sequenced peptides / proteons
Frederick Sanger (Insulin, 1955)
When was the first gene sequences
1972
First genome found
1977
Human genome project is launched in
1990 ($3B)
The human genome has _ pairs of
22 pairs of autosomes, 1 pair of sec chromosomes
Haploid
Protein
a linear polymer of amino acids that folds into a particular shape
RNA
a polymer of nucleotides that is an intermediary in the synthesis of proteins from instructions in DNA
Intron
part of a gene that does not contain protein coding information
Complimentary
G–C and A–T base pairing in DNA through hydrogen bonds
Mutation
alteration of DNA sequence
Exons
part of a gene that can contain protein coding information
Chromosomes
DNA structures that contain genes
Gene
DNA information for a single function, such as production of a protein
Genome
the entirety of an organism’s hereditary information
Nucelotide
subunit of the DNA macromolecule
DNA
a double-stranded polymer of nucleotides that stores the inherited blueprint of an organism
The only one of the four bases in RNA that is not in DNA
Uracil
a macromolecule composed of a string of subunits
Protein and DNA
four different subunits
DNA
Composed of Nucleotides
DNA
20 different subunits
// composed of amino acids
Protein
contains a code used to generate other macromolecules
DNA
performs chemical reactions
Protein
are the triplets usually written as DNA or
RNA? Why do you think this is?
The triplets are usually written as RNA because of the various combinations of amino acids. It is used to specify which amino acid is apparent.
There are two amino acids that are each specified only by a single triplet. Identify these two amino
acids and the corresponding nucleotide triplets.
AUG - Met (start) // UGG - Trp
If you know the sequence of amino acids in a protein, can you predict the exact sequence of
nucleotides in the gene that specifies that protein? Why or why not?
No, an amino acid can correspond to more than one codon.
Why do scientists think that all forms of life on earth have a common origin?
All scientists think that all forms of life on earth have a common origin because many distinct organisms have the same genetic code as well as similar amino acid sequences which encode proteins.
