Question | Answer |
Unicellular or multicellular eukaryote with chloroplasts but no stems, roots, or leaves | Kingdom Protista (algae) |
A unicellular prokaryote with cell walls that contain peptidoglycan | Kingdom Bacteria |
Non-motile unicellular or multicellular eukaryote with cell walls containing chiin or cellulose | Kingdom Fungi |
A unicellular prokaryote with cell walls that do not contain peptidoglycan | Kingdom Archae |
Unicellular (only) motile eukaryote without cell walls and without chloroplasts | Kingdom Protista (protozoa) |
What are dehydration synthesis reactions used for? | Used to build larger molecules |
Would dehydration synthesis reactions be catabolic or anabolic? | Anabolic |
Name one cellular function of carbohydrates. | Fuel storage, element structure |
Name one cellular function of triglycerides. | Membrane, energy storage |
Name one cellular function of proteins. | Enzymes, movement, structure, regulation |
Why do we use immersion oil? | It minimizes the refraction of light rays by air. |
Resolution of the eye | 1X at 0.2 micrometers |
Resolution of compound light microscope | 1000X at 1 micrometer |
Resolution of Transmission Electron microscope | 500000X at 1nm |
Darkfield Microscopy | Good for live specimens |
Phase contrast microscopy | Good for live specimens and bright/dark image on grey background. Provides detail on internal structures. |
Brightfield microscopy | Specimens are usually colored and good for live specimens |
Confocal microscopy | Laser illuminates layers of fluorescent specimens |
What color are gram positive cells? | Purple |
What causes cells to stain positive in the gram stain? | Thick peptidoglycan layer |
How is this structure different in cells that stain positive in the acid fast stain? | The cell wall has more lipids and mycolic acid and is much thicker. |
What color are cells that show a positive acid fast staining reaction? | Red |
What type of stain would you use to see Mycobacterium tuberculosis? | Acid-fast stain |
TEM | Examine the mitochondria of yeast cells. Examine the ribosomes of prokaryotic cells. |
SEM | HIV virus already attached to the surface of T-cells |
LM | Observe positive chemotaxis of bacteria. Immunofluorescent detection of the Syphilis bacterium. |
WHy is the resolution for Electron microscopy higher than for light microscopy? | Because the wavelength of electrons is shorter than that of light. |
Name 2 of the disadvantages to electron microscopy. | Have to cut into tiny pieces. No live specimens. Have to be in a vacuum. Very expensive. |
Eukaryotic Cells | Linear chromosomes, true nucleus, have organelles, 80s ribosomes, mitosis, larger cell size. |
Prokaryotic Cells | circular chromosomes, nuclear area, do not have organelles, 70s ribosomes, binary fission, smaller cell size. |
A bacterium with peritrichous flagella that was undergoing positive chemotaxis would: | Show more counterclockwise rotation of the flagella resulting in longer runs when moving toward the stimulus. |
WHich metabolic reactions occur in the mitochondria? | Cellular respiration |
WHich metabolic reactions take place in the chloroplast? | Photosynthesis |
List 2 structures found in organelles that support the embisimbiotic theory. | Circular chromosomes, multiple membrane layers, 70s ribosomes |
Explain how scientists think the mitochondria and the chloroplast originated. | A eukaryotic cell engulfed a prokaryotic cell but did not digest it because it gave more metabolic ability. |
Describe in detail how endocytosis occurs. | Uses energy to bring something outside the cell into it. |
When placed in a hypotonic solution describe what would happen to a bacterial cell. | Because there is less salt outside the cell it would bring water inside the cell and the bacterial cell would swell. |
What do you predict would happen to protozoa in a hypotonic solution. | They have a cell that would swell and burst because they do not have cell walls. |
How do you predict potassium ions cross the plasma membrane and why? | WIth the help of a transporter protein because potassium ions are charged. |
To maintain this concentration of potassium ions in the cytoplasm, would the cell use passive or active transport, why? | Active transport because brought in K+ froma concentration of low to high, had to use energy to do so. |
How does an enzyme lower the activation energy of a reaction? | ENzyme brings together 2 substrates in proper orientation, puts strain on their bonds until a new bond is formed. |
What is the incoming energy source for the ETC? | NADH |
What does ETC create to be used by ATP synthase to produce ATP? | proton gradient |
The ETC creates a proton gradient that is used by what to produce ATP? | ATP synthase |
Purpose of glycolysis | breakdown glucose into energy |
Purpose of Krebs cycle | oxidize pyruvate to CO2 for more energy |
Pupose of fermentation | continue glycolysis by changing NADH to NAD+ |
Define anaerobic respiration and give an example of a reaction. | Where the final electron acceptor is something other than O2. Does not require O2. Ex. Nitrate to Nitrite. |
Why would catabolism of a six-carbon fatty acid yield more energy than the catabolism of a six-carbon carbohydrate? | Because the fatty acid would be converted into 3 acetyl co a vs. 2. |
Why do our lives depend on photosynthetic organisms? | To convert CO2 into carbohydrates for us. |
What are humans? -troph wise. | Chemoheterotrophs |
Name the products of the light reactions of photosynthesis. | ATP, NADH, O2 |
Which products of photosynthesis are used by the dark reactions? | ATP, NADH |
Give an example of a microbe that is a photoautotroph. | Purple sulfur bacteria |
Which metabolic reaction would you expect to find in a photoautotroph but not in a photoheterotroph? | Dark reaction |
Which metabolic reactions would you expect to find in a photoheterotroph but not in a chemoheterotroph? | Light reaction |
Which growth phase is best for conducting biochemical tests on bacteria? | Log phase |
Why is there no increase in the number of cells during lag phase? | Because the cells are changing their metabolism to adjust to the conditions. |
What is occurring in cultures that are in stationary phase? | Death rate is equal to growth rate. |
When graphing a bacterial growth curve, what units are plotted and on what axis? | Log(#cells) on y axis, time on x axis. |
List the methods that can be used to obtain pure cultre. | Streak plate, spread plate, pour plate |
Which methods can also be used to enumerate cells in a culture? | Spread plate, pour plate |
DMC | Could be used for cells that do not grow in culture, but requires large numbers of cells in sample. |
MF | Method that can be used with < or = 2 organisms/mL in sample |
MPN | Uses tubes to culture microbes, can detect > or = 3 org/mL and analysis of results is simple compared to other methods. |
SPC | serial dilutions are used and pure culture of organisms results. |
Obligate Aerobe | can only grow in presence of O2. |
Facultative thermophile | can grow below but optimum 50-60 degrees C |
How would you examine potato salad samples for contamination if the level is predicted to be 30-300 orgs/mL? How would you determine the total number of gram + bacteria? | SPC and plate on selective media for growth of gram +. |
Is a media that causes color change and suppresses growth of a particular bacteria selective, differential, or both? | Both |
T/F: Both eukarytoes and prokaryotes use RNA Polymerase for transcription. | True |
T/F: In prokaryotes, ribosomes perform transcription in the cytoplasm. | FALSE, doesn't perform transcription in the cytoplasm. |
T/F: mRNA's produced from operons are spliced to remove introns. | FALSE, prokaryotes not operons |
T/F: only eukaryotes have multiple RNA polymerases. | FALSE, prokaryotes also |
T/F: 3'tails and 5'caps are added to prokaryotic mRNA's | FALSE, added to Eukaryotic mRNA's |
T/F: DNA polymerase must copy the chromosome before transcription can occur | FALSE, before cell division can occur |
What would happen if an enzyme responsible for splicing was missing or defective in a cell? | The mRNA's would have introns which wouldn't work for translation. |
Repression | Saves ATP, reacts slower to changing growth conditions |
Feedback inhibition | Uses more ATP, can react quicker to changing growth conditions |
Describe what would happen at the lac operon when lactose is present and glucose levels are high. | Repressor can't bind operator, RNAP binds promoter, low levels of transcription. |
If a frameshift mutation were to occur in the first structural gene of the lac operon, what would happen? | It would change the reading frame of the nucleotides. What would happen would then depend on what was read from the mRNA. |
Briefly describe the results of the fluctuation test and what it proved. | FLuctuation test proved that mutations were random and not induced by exposure to antigens. |
Name the enzyme used for PCR and two other components of a PCR reaction. | Taq DNA polymerase, primers, target DNA, and plenty of the 4 nucleotides. |
If you run a PCR reaction for 10 cycles, you will have now many times the amount of DNA you started with? | 2^10, use 2^#of cycles |
Amp^r gene | select for cells that get/keep the plasmid |
Restriction enzyme sites | tell DNAP where to bind and copy the plasmid |
What is recombinant DNA? | Genes from 2 organisms are combined and transgenic cells pass recombinant genes to offspring. |
How is recombinant DNA created in the lab? | Created in lab bacteria by using restriction enzymes to cut at certain points in the DNA to insert vectors. |
Give 2 examples of how the use of genetic engineering technology has benefitted the pharmaceutical industry. | Able to produce recombinant insulin instead of having to produce it in pigs. Abel to make recombinant human growth hormone instead of using cadaveors. |
Several cultures of different gram - bacteria are all resistant to the same 4 antibiotics. What could expalin the acquired resistance and what would you expect to find in these bacteria? | Conjugation and transfer of a resistance transfer factor. Expect to find the resistance genes in eact bacteria. |
Outline the steps you would take to create recombinant cells that produce anti-hemophilic factor VIII for use by hemopheliacs. | Use enzymes to cut at desired location on DNA for the factor, use plasmid to introduce factor to cells, test for the factor in the created cells, culture them if the factor is there and purify them. |
Describe 2 ways bacteria and archae differ at the cellular level. | Bacteria no histone, Archae have histone. Bacteria have linear fatty acid, Archae have branched fatty acid. Bacteria contains peptidoglycan, Archae do not. Bacteria have single RNA, Archa have multiple RNA. |
For 2 of the 3 main groups of Archae, list the group name and give an example. | Methanogen - Methanobacterium. Extreme halophite - Halobacterium. Extreme acidophiles - Sulfobolus. |
In addition to PCR, which other 2 identification methods can differentiate between not only species but strains? | Phage typing and Immunological testing. |
What are the three possible methods an animal virus can use to enter the cell? | Direct entry, membrane fusion, endocytosis |
Which method requires an envelope? | Membrane fusion |
Explain how animal viruses can exit cells. | Lysis for naked viruses, budding for enveloped viruses. |
Describe the replication cycle of a lytic bacteriophage. | Adsporption - attach to host cell. Penetration - uses direct entry for a single strand of nucleic acid. Biosynthesis - genomes are replicated. Maturation - particles are assembled. Release - exit cell. |
For HIV to attach to and enter cells: | The viruse uses proteins gp120 and gp41 to attach to host cells that have CD4 and CXCR4/CCR5 on their surface, then HIV enters by membrane fusion. |
Describe how HIV convert its genome into a provirus and describe any specific proteins/enzymes required for these steps. | ssRNA -RT-> dsDNA -Integrase-> provirus. RT and Integrase are viral enzymes, HIV then replicates using host cell enzyme RNAP. |
How does infection with PrPsc cause disease? | PrPsc + PrPc -> 2PrPsc Replicates the misfolded protein damagine the brain tissue. |
Is the DNA sequence that encodes PrPsc the same as the gene for PrPc? Why or why not? | Yes, protein is misfolded not mutated. |
List 2 methods that have been used to prevent/postpone the arrival of vCJD in the U.S. | FDA ban on using cow blood as a substitute for calves milk. Ban on feeding cow carcasses and pieces to other cows. |
Name 2 other prion diseases mentioned in the notes. | Kuru - humans. CWD - deer/elk. Scrapie - goats. Mad Cow - cow. |