BIO SCI 98 Study Guide - Spring 2018, Comprehensive Midterm Notes - Dna, Messenger Rna, Protein
12 Oct 2018
School
Department
Course
Professor
BIO SCI 98
MIDTERM EXAM
STUDY GUIDE
Fall 2018
CHAPTERS 6 (192-203),15 (pp. 520-546) & 16 (pp. 554-562)
The central dogma
Replication = DNA → Transcription = RNA → Translation = protein
50 X 10^12 = 50 trillion
Gene expression: large scale, tightly controlled
Humans: 50 x 1012 cells, each with the same 30,000 genes
Our proteins are 99% similar to chimpanzee proteins
Transcription
-The process by which genetic information represented by a sequence of DNA nucleotides
is copied into newly synthesized molecules of RNA, with the DNA serving as a template
Replication (DNA) Transcription (RNA)
- both strands of DNA are copied
(complementary sequences)
- all DNA is copied (the entire genome)
- primer needed for DNA polymerase to
synthesize complementary strand 5' → 3'
- bases are A, T, C, G
- Selective stretches of DNA are copied into
RNA
- only one strand of DNA is used as a
template
- RNA polymerases do not require a primer
for complementary RNA synthesis
- template is copied 3' → 5' to make 5' → 3'
RNA
- Bases are A, U, C, G
RNA forms
-Messenger RNA
-Transfer RNA
-Ribosomal RNA
-Other RNAs (snRNPs, etc)
-We will focus mainly on mRNA transcription (directs protein synthesis)
Chemical differences between RNA and DNA
find more resources at oneclass.com
find more resources at oneclass.com
The inherent chemical properties of the nucleotide bases and of the sugar backbone are key to
the specific functions of DNA (long-lived, stable) and RNA (short-lived, labile)
Uracil belongs in RNA
-DNAs are long-lasting while RNAs are short lived
-Uracil is "cheaper" for RNAs because it is structurally simpler than thymine
-Less energy to make
Uracil wouldn't work in DNA
-Cytosine in DNA can deaminate and become uracil
-If uracil were used in DNA in place of thymine, repair enzymes would not be able to
distinguish the appropriate use of this base from deaminated cytosine
find more resources at oneclass.com
find more resources at oneclass.com
Document Summary
Replication = dna transcription = rna translation = protein. Humans: 50 x 1012 cells, each with the same 30,000 genes. Our proteins are 99% similar to chimpanzee proteins. The process by which genetic information represented by a sequence of dna nucleotides is copied into newly synthesized molecules of rna, with the dna serving as a template. Both strands of dna are copied (complementary sequences) All dna is copied (the entire genome) Primer needed for dna polymerase to synthesize complementary strand 5" 3" Selective stretches of dna are copied into. Only one strand of dna is used as a template. Rna polymerases do not require a primer for complementary rna synthesis. Template is copied 3" 5" to make 5" 3" We will focus mainly on mrna transcription (directs protein synthesis) The inherent chemical properties of the nucleotide bases and of the sugar backbone are key to the specific functions of dna (long-lived, stable) and rna (short-lived, labile)
