From Genes to Proteins Flashcards
What are 2 examples of structure fits function in this unit?
- DNA- its structure codes for specific proteins that give us our individual looks and perform functions throughout our entire body
- enzymes- a specific structure of a protein (enzymes) can only catalyze specific molecules
How do we see God in DNA?
- John 1- the Word spoke things into existence and DNA is a language that creates (codes) for things
- unique- everyone’s walk with Christ is unique, everyone’s DNA is unique and different
- unity and diversity- Trinity (3 persons, 1 God) and everyone has DNA but everyone’s looks are different
- identity from God in that we are sons and daughters of Him, identity from DNA = looks
What is the Central Dogma of Biology and who founded it?
DNA→RNA→proteins (by this process, traits are expressed), Watson, why? 1. important in bodily structure and 2. enzymatic activity → control every chemical reaction in the body
What is gene expression?
the process by which DNA directs the synthesis of proteins
Where is DNA transcribed?
nucleus
Where does RNA processing occur?
nucleus
Where does translation occur?
ribosomes in the cytoplasm (protein synthesis)
Generally, what is transcription and translation?
- copying of the DNA instructions into RNA
2. converting nucleotide info into protein info
What are proteins’ important functions?
- important in bodily structure
2. enzymatic activity → control every chemical reaction in the body
What are proteins made of?
chains of amino acids, called polypeptides (immature proteins)
How is proteins synthesis an example of intelligent design?
has to be flexible enough to make thousands of proteins but precise enough to manufacture them correctly
What do the four pairs of DNA form?
a genetic alphabet
What are codons?
3 letter “words” of the mRNA, triplets of bases which code for a particular amino acid
How many combinations are there of the 4 bases to form codons? (ie. how many codons are there?)
64
How many amino acids are there?
20
What are the stop and start codons and what are their functions?
they stop and start the making of a protein, Stop codons: UAG, UGA, UAA, start codons: AUG
What is a reading frame?
reading symbols in the correct grouping, mRNA needs to make sense to code for codons
How does RNA differ from DNA?
- single stranded (small enough to fit through nuclear pores)
- contains uracil instead of thymine
- ribose sugar instead of deoxyribose sugar
What are the structures and functions of mRNA, rRNA, and tRNA? And what do they stand for?
mRNA (messenger RNA): single stranded and made of RNA nucleotides, carries the code from DNA to the ribosome
rRNA (ribosomal RNA): folds up with some proteins to make a ribosome, protein synthesis (as a ribosome)
tRNA (transfer RNA): t-shaped strand of RNA with an anticodon (3 unpaired bases attracted to codon) at one end and an amino acid at the other end, pick up amino acids in the cell and transfer them to the ribosome
Describe the structure and function of a ribosome.
structure: made up of rRNA, large (tRNA) and small (mRNA) subunit, A (arrival) site, P (peptide bonding) site, E (exit) site, function: organelle where translation occurs
What are the 3 steps involved in transcription?
initiation, elongation, and termination
Describe initiation.
RNA polymerase binds to promoter (series of bases to which RNA polymerase is attracted), causes DNA strands to unwind and polymerase begins to copy the DNA at the start point on the template strand into mRNA
Describe elongation.
RNA nucleotides are used to form mRNA, a copy of the DNA’s template strand, RNA polymerase moves in a 5’ → 3’ direction
Describe termination.
mRNA strand is released once completed, RNA polymerase detaches from DNA
Describe RNA processing.
the maturing of mRNA, 5’ Cap of guanine is added to the 5’ end of the mRNA (helps mRNA attach to the ribosome properly), Poly-A tail (a bunch of adenines) added to 3’ end, maybe to strengthen or stabilize mRNA for the journey to the ribosome (holds off other enzymes), RNA splicing- introns are non-coding segments of mRNA which are removed, exons are segments of mRNA which remain and are expressed: spliceosome cuts out introns with SNURPS in them to do so, exons come together, mRNA exits the nucleus
Who discovered the spliceosome?
Joan A. Steiz, 1st woman allowed in James Watson’s lab, studied RNA whole life
Describe translation.
mRNA attaches to binding site on small subunit of ribosome, tRNA picks up specific amino acids to take to large subunit of ribosome, arrives at A site, covalent bond between tRNA in P site (carrying the amino acid chain), moves to P site (amino acid now attached to chain), then moves to E site and can actually come back again with a different amino acid, this continues until stop codon
What are polyribosomes?
a string of ribosomes used to speed up the process of protein synthesis, all translating a mRNA at the same time
After a polypeptide is formed, 4 steps of folding must occur to the protein to mature it. What is this called?
Post Translational Modifications
What are mutations?
any change in DNA or genetic info
silent mutations
a mutation that has no negative effect because a substitution might not be harmful if it just makes a different kind of enzyme/protein
What do mutations lead to?
malformation of proteins
