BIOL41 Lecture Exam2 -1

all catabolized to end up as Krebs cycle/metabolic precursors

 polysaccharides broken down outside of cell by exoenzymes -> mono/disaccharides transported into cell -> glycolytic intermediate

tri/diglycerides broken down outside of cell by secreted lipases -> FFAs, glycerol transported into cells -> B-oxidation -> acetyl-CoA/glycerol to glycolytic pathway

protein in environment broken down by enzymes -> amino acids transported into cell -> conversion into metabolic intermediates

polysaccharides

tri/diglycerides

organized structure of DNA and protein

• entirety of an organism's hereditary information
• includes both the genes and the non-coding sequences of the DNA/RNA

• circular
• double stranded
• typically only 1 chromosome

• linear
• double stranded
• several chromosomes

DNA polymerase

helicase

each new double-helix has 1 older strand from the previous cell division and 1 newly synthesized strand

• small, circular external, double-stranded DNA in prokaryotic cells
• can give extra advantages to bacteria (ie: antibiotic resistance)

• 1) unit of info to form protein
• 2) physical location on chromosome

process by which information from a gene is used in the synthesis of a functional gene product (protein, rRNA, tRNA)

yields an RNA product from the DNA

RNA polymerase

• template is the strand that is actively being transcribed into RNA and will eventually be translated into protein
• non-template strand is the strand of DNA which is not actively being transcribed/translated into protein

promoters present 35 or 10 nucleotides upstream of gene to be transcribed (where proteins assemble)

cytoplasm

nucleus

any nucleotide sequence within a gene that is removed by RNA splicing while the final mature RNA product of a gene is being generated

turns mRNA into protein

• carries coding info for amino acids
• sent out of nucleus to cytoplasm/ER

section of mRNA with 3 nucleotides that code for specific amino acids

• nonsense codons
• UAG, UGA, UAA
• where translation ceases

• transfer RNA
• stays as RNA, used as is
• molecule that brings amino acid to ribosome
• has anticodon complimentary to codon

set of nucleotides complimentary to a codon

• complex that brings codons and tRNA together to form amino acid chain for protein synthesis during translation
• made of large and small subunits and several polypeptides

peptide bonds

many ribosomes read one mRNA simultaneously, progressing along the mRNA to synthesize the same protein

• 1) single genome per cell (changes seen easier/quicker)
• 2) fast growth rates
• 3) enormous numbers of offspring
• 4) easily sequenced

• "strange eater"
• doesn't consume the same as a normal organism of its species

• gene (DNA) responsible for phenotype
• single genotype change in haploid organisms = phenotype change

• observed characteristic representative of genotype
• need at least 2 mutations to change phe of diploid organisms

change in DNA -> change in amino acid translated

change in DNA leading to a stop codon 

• 1) spontaneous error
• 2) base analogs (ex: bromouracil incorporated instead of thymine, but base pairs with guanine)
• 3) UV radiation (covalently bound thymine dimers caused)

compound that causes mutations in DNA

compound that causes mutation in DNA that leads to cancer

• 1) oncogenes 
• 2) tumor suppressors

• control when cell decides to divide
• normally pushes a cell through DNA synthesis

Ames test (look for mutation that changes phe)

• 1) pour plates with his(-) media
• 2) spread plate with his(-) Salmonella auxotroph (can't make His), add disk with test chemical in center
• 3) POSITIVE result: mutated bacteria (only mutated bacteria can grow, bc chemical reversed original mutation) -> SUGGESTS SUSPECTED CHEMICAL IS MUTAGENIC

mixing of 2 types of DNA inside 1 cell

similar sequences of DNA (often bc of same origin)

• sharing of genetic info from 1 cell (donor) to another (recipient)
• rare

sharing of genetic information from parent to progeny

• "naked" DNA in environment taken up by bacterial cell
• -recombines or catabolizes for amino acids

• 1) bacteriophage injects DNA into bacteria then
• 2) replicates but accidentally
• 3) packages bacterial DNA and
• 4) injects DNA into a similar bacterial cell leading to
• 5) recombination of homologous DNA

VIRUS is used to move bacterial DNA

• very closely related cells pass DNA (F plasmid) through a pilus
• must have 1 cell with ability to make pilus, and 1 cell without ability

use of living systems and organisms to develop or make useful products

use naturally occurring gene transfer features of microbes to study and manipulate genes

• 1) To eliminate undesirable phenotypic traits in humans, animals, plants, and microbes. 
• 2) To combine beneficial traits of two or more organisms to create valuable new organisms, such as laboratory animals that mimic human susceptibility to HIV.
• 3) To create organisms that synthesize products that humans need (vaccines, Ab's)

• cloned gene
• plasmid with gene of interest ligated into it

• cut DNA at specific sequences
• enzymes naturally found in bacteria/fungi as defense mechanism

collection of DNA fragments that is stored and propagated in a population of micro-organisms

• 1) extract DNA
• 2) cut DNA of interest and plasmid with RE's
• 3) ligate digested fragments with digested plasmid
• 4) transform and grow in bacteria

• polymerase chain reaction
• uses DNA pol from thermophilic bacteria
• makes many copies of a specified DNA sequence
• useful for amplifying scarce DNA

detects gene in DNA

• 1) DNA separated by agarose gel
• 2) transferred to porous membrane
• 3) probed with radioactive probes complimentary to sequence of interest
• 4) probes expose photographic film if bound to DNA of interest

• consists of molecules of single-stranded DNA, either genetic
• DNA or cDNA, immobilized on glass slides, silicon chips, or nylon membranes
• single strands of fluorescently labeled DNA in a sample
• washed over an array adhere only to locations on the array
• where there are complementary DNA sequences

can be used to monitor gene expression, diagnose infection, ID organisms in an environmental sample