Nursing Cell Biology Final Exam
4. Describe the role hexokinase plays in the first step of glycolysis. (Cellular Respiration)
hexokinase takes a phosphate group off of glucose and makes it glucose 6 phosphate. taking a phosphate group- an ATP is changed to ADP.
Distinguish between scientific laws, theories, and hypotheses. (Nature of Science/ Scientific Method)
laws: correct everytime when tested so far theories: very well supported statement hypothesis: educated guess
Explain the role of peer review in science. (Nature of Science/ Scientific Method)
needs to be proven needs to be repeated by others or else such evidence can be skewed
10. Describe the advantages and disadvantages of fat as an energy storage molecule compared to glycogen. (Molecules of Life)
- Fats are more dense due to them being nonpolar (hydrophobic) -Fat moves through the bloodstream but can cause blockages
9. Distinguish between fats and oils in terms of structure and function. (Molecules of Life)
- Oils are unsaturated and contain double bonds -the double bonds create a kink in the chain. this causes unsat. fats to be liquid at room temp - Fats are saturated and are only single bonded
24. Recognize the three components of nucleotides. (Molecules of Life)
- sugar (deoxyribose) - phosphate - 1 of 4 bases (AGCT)
Given the electronegativity of two atoms predict the type of bond they will form. (Chemistry/ Properties of Water)
->.4 nonpolar -<.4 polar 1.67 polarity is considered ionic
14. List the general characteristics of bacteria that account for their great success on earth. (Intro to Cells/ Prokaryotes)
-Abundant -Ubiquitous -Metabolically Diverse -Masters of Adaptation ( rapid reproduction and mutation)
9. Distinguish between collision and binding. (Enzymes)
-Collision- when substrates hit the enzyme -Binding- is when the substrate and enzyme connect and bind together.
2. Provide specific examples of cytosolic proteins, membrane proteins and secretory proteins. (Eukaryotic Cell Structure and Function)
-Cytosolic proteins: hemoglobin, hexokinase, cytoskeletal proteins -Membrane proteins: integral, peripheral -Secretory proteins: hormones, enzymes
Be able to distinguish proper from improper research conclusions. (Nature of Science/ Scientific Method)
often involves a statistician to reach a correlation correlation does not equal causation Restricted to statements which can be directly supported by the data collected from the experiment
Be able to recognize when blinded studies are needed and provide examples of single blind and double blind studies. (Nature of Science/ Scientific Method)
-Double blind is needed only when there is concern about the proctors bias affecting the results -They are expensive however and any case in which they are not needed, a single blind is preferred
19. List the 5 types of interactions that contribute to a protein's tertiary structure. (Molecules of Life)
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10. Design experiments to test the effect of each of the following variables on the rate of an enzyme catalyzed reaction: [enzyme], [substrate], temperature and pH. Be prepared to explain and graph expected results. (Enzymes)
-If you increase the amount of enzymes the rate of reaction will keep increasing until there is no substrate left. -If you increase the amount of substrate the rate of reaction will increase until the enzymes are doing work as fast as they can so it becomes saturated. -If you increase the temperature it will increase then decrease because the movement of substrates will increase the amount of collisions that happen. Then when it gets too high the enzyme will actually denature itself. -If you increase the pH the rate of reaction will go up around 5 and goes straight back down around 8. the enzyme then is broken
Provide examples of isotopes and explain their usefulness in research and medical diagnostics. (Chemistry/ Properties of Water)
-Isotopes are atoms that differ from their normal state in number of neutrons yet are still the same element -Often used for medical scans/tracing the path of molecules through the body -ex: GAmma rays, Beta, X rays
Describe the three subatomic particles. (Chemistry/ Properties of Water)
-Protons and Neutrons are in the nucleus -Electrons are in the electron cloud
4. Describe the role of phospholipids in cell membranes and the factors that influence the permeability of the phospholipid bilayer. (Cell Membrane Structure and Function)
-Short & unsaturated hydrocarbon tails = higher permeability and fluidity -Long & saturated hydrocarbon tails = lower permeability and fluidity
9. Distinguish between simple diffusion, facilitated diffusion and active transport. (Cell Membrane Structure and Function)
-Simple diffusion - molecules can pass through the phospholipid bilayer without the assistance of membrane proteins -Facilitated diffusion - use membrane proteins such as gates and channels, most cells use facilitated diffusion -Active transport - move less of them to where there is more with the assistance of
15. Define symbiosis, distinguish between the three types of symbiotic relationships and provide specific examples of each. (Intro to Cells/ Prokaryotes)
-Symbiosis : a relationship which two species live in close association (not always positive or negative) -Mutualism : both symbiotic organisms benefit (bees and flowers) -Parasitism : where a parasite harms, but does not kill the host organism, parasites that cause disease are pathogens (fleas on dogs) -Commensalism : one organisms benefits, while the other is neither helped nor harmed (barnacles and whales)
11. Describe the specific mechanisms by which tetracycline and penicillin help fight bacterial infections in humans. Explain why these poisons do not damage human cells. (Intro to Cells/ Prokaryotes)
-Tetracycline : Targets ribosomes of a bacteria. Doesn't bother us because of our slight variations within our ribosomes -Penicillin : targets peptidoglycan enzyme, the cell wall then can't form, allowing the body to destroy the bacteria. Doesn't harm us because we don't have cell walls
Explain the relationship between sample size and statistical significance. (Nature of Science/ Scientific Method)
-The larger the sample size the more reliable the results are -Statistical significance is not just that something is indicated by the results, but that those results are unlikely to have occured by random chance
11. Distinguish between allosteric inhibition and allosteric activation and provide specific examples of each. (Enzymes)
-allosteric inhibition: changes the shape of the enzyme so the substrate cannot bind -allosteric activation: changes the shape so the active site is bigger allowing the substrate to attach more easily.
Explain the benefits and limitations of experiments on humans, human cells and animal models. (Nature of Science/ Scientific Method)
-ethics -humans cannot be exploited -variables need to be humanly safe within limits -consent is needed
3. Describe the events that lead to the non-enzymatic conversion of 2 H2O2 into 2 H2O + O2. (Enzymes)
-it is a spontaneous reaction, which means that the rate in which it will be converted will be slow without an enzyme present.
Be prepared to explain the important aspects of experimental design illustrated in the clinical trial (RCT) on the effects of caffeine on short term memory in elderly. (Nature of Science/ Scientific Method)
-the control group and experimental group should be identical in all ways but the amount of caffeine. -Sample size must be large enough to have statistically significant results. -Randomization: Race, age, and lifestyles should be equally represented.
Describe the difference between CO2 and H20 that accounts for their different physical and chemical properties. (Chemistry/ Properties of Water)
-water molecules arent symmetrical while co2 is -water molecules are polar. (one side neg and one pos)
3. List the four classes of biological molecules and their building blocks. (Molecules of Life)
1. Carbs (sucrose, glycogen, cellulose) 2. proteins (amino acids, insulin, hexokinase, hemoglobin, antibodies, actin) 3. Lipids (oil, fat, phospholipids) 4. Nucleic Acids (DNA, RNA)
6. List three significant structural differences between bacterial cells and eukaryotic cells. (Intro to Cells/ Prokaryotes)
1. DNA found in nucleoid and plasma (not membrane bound) v Inside membrane bound nucleus 2. Internal membranes only in photosynthetic species v Large number and variety of organelles 3. Cytoskeleton is limited in extent v extensive, usually found throughout volume of cell
9. Contrast the structural features of gram negative and gram positive bacteria and explain why penicillin is ineffective in treating gram negative bacteria. (Intro to Cells/ Prokaryotes)
1.Gram Negative : Outer membrane, peptidoglycan layer, and plasma membrane ( E.coli, Gonorrhea) 2.Gram Positive : Peptidoglycan layer and plasma membrane (Anthrax, Tetanus) 3.Gram negative bacteria has a protein layer that penicillin can't travel past.
12. Describe the events that increase the likelihood of the evolution of antibiotic resistance. (Intro to Cells/ Prokaryotes)
1.Patient starts taking antibiotics 2.Patient then stops taking medicine/forgets to take medicine 3.Some bacteria has died from antibiotics that have been taken, while the bacteria still living in the body has begun to multiply 4.The bacteria is now resistant to the antibiotic, so the infection the patient has is now stronger and isn't affected by the antibiotic
4. Our current classification scheme divides eukaryotes into four kingdoms. Name these and list the major distinctions between them. (Intro to Cells/ Prokaryotes)
Animalia-multicellular Plantae- have cell wall, chlorophyll Fungi protista
Compare and contrast science with other ways of learning (Nature of Science/ Scientific Method)
Art- it is individualistic and depends on the creator Math- it is the truth by definition. you must conform since there is only one right answer. theology- based on faith. often asks big questions without answers.
3. Name the three domains of life. (Intro to Cells/ Prokaryotes)
Bacteria, Archaea, Eukarya
2. List the six most common elements found in biological molecules and be able to recognize the six functional groups. (Molecules of Life)
CHNOPS
1. Describe the characteristics of carbon atoms that make them uniquely suited to form the framework for biological molecules. (Molecules of Life)
Carbon has four valence electrons that allows them to bind with many molecules basis of electronegativity
2. Describe the contribution Louis Pasteur made to the cell theory. (Intro to Cells/ Prokaryotes)
Cells arise from preexisting cells, not spontaneously from nonliving material.
8. Describe how the absence of chloride channels causes cystic fibrosis. (Cell Membrane Structure and Function)
Chloride pumps do not function as well, if at all → lack of chloride ions in the extracellular fluid creates a thick extracellular fluid which prevents the rate at which cilia moves, promoting the growth of bacteria
Be able to recognize proper experimental design. (Nature of Science/ Scientific Method)
Controlled vs. experimental variables Sampling error
22. Explain why cyanide poisoning shuts down glycolysis. (Cellular Respiration)
Cyanide is considered to be toxic because it binds to cytochrome c. it cannot transport any electrons to oxygen. This blocks the further passage of electrons throughout the chain, halting ATP production. Since no ATP is made, the electron transport chain stops working. the concentration of protons build up and the gradient becomes large. Therefore, the person is deprived of chemical energy to perform the many numerous processes that sustain life and the person dies.
4. Provide examples of human proteins and their functions. (Molecules of Life)
DNA/RNA- helps copies genetic code ATP- releases energy when hydrolyzed in cells (Primary, Sec ondary, Tertiary, Quarternary Structure
23. Describe how DNP causes weight loss and why this drug is sometimes fatal. (Cellular Respiration)
DNP causes weight loss by making cellular respiration less efficient. The majority of ATP (molecules used for energy) is produced in the mitochondria. Through a series of oxidation-reduction chemical reactions a higher concentration of protons is built up in the inter-membrane space of the mitochondria than the proton concentration in the mitochondrial matrix. The inter-membrane space is separated from the matrix by a membrane that protons can not cross on their own. Instead they cross through a protein called ATP Synthase which produces ATP as the protons go through it. This is fatal as it may cause overheating of the body.
2. Describe the experiments that led to the fluid-mosaic model of cell membranes. (Cell Membrane Structure and Function)
Freeze fracture electron microscopy because the steps involve freezing and fracturing the membrane before examining it with a scanning electron microscope. Allowed researchers to split cell membrane and view the middle of the structure. Membranes are a mosaic of phospholipids and different types of proteins.
Be prepared to draw the electron configuration of the first 17 elements in the periodic table (given the atomic number). (Chemistry/ Properties of Water)
H,He,Li,Be,B,C,N,O,F,N,Na,Mg,Al,Si, P,S,Cl
Distinguish between ionic bonds, polar covalent bonds and non-polar covalent bonds and provide examples of each. (Chemistry/ Properties of Water)
Ionic- Between a metal and a nonmetal Covalent-Very strong, shared electron clouds Nonpolar- Doesn't have electrically charged (polarized) ends
5. Explain what it means to say that the 3rd step of glycolysis is the first "committed step". Discuss glycogen synthesis in your answer. (Cellular Respiration)
It is the first committed step so it doesnt go back and make glycogen.
Discuss the limitations of science. (Nature of Science/ Scientific Method)
Limited to observable, measurable phenomena
5. Describe diseases that result from malfunctioning lysosomes. (Eukaryotic Cell Structure and Function)
Lysosomal storage disorders are a result of not being able to properly break material down
2. Describe the role of NAD+ in the first 3 phases of cell respiration. (Cellular Respiration)
NAD+ is taken to the electron transport chain
Distinguish between RCTs, case-control studies and cohort studies and be prepared to discuss the advantages and disadvantages of each. (Nature of Science/ Scientific Method)
Randomized- Study subjects are randomly assigned to either the control or experiment groups Blind Studies-Subjects are unaware if they are in the control or experimental group Double Blind- Both subjects and scientist are unaware what group subjects are assigned to Case Control Study- Compare past exposures/behaviors of people who have already developed disease (case) with and equivalent group who have not had disease (control)-- recall bias Cohort Study- Follow a group of people for many years, Try to find characteristics that distinguish people who get disease from those who don't
5. Describe the role of carbohydrates in cell membranes. (Cell Membrane Structure and Function)
Responsible for cell to call recognition. Carbohydrates covalently linked to glycoproteins and glycolipids on the outside of the phospholipid bilayer. Ex: reason for different blood types
1. Describe the contributions Robert Hooke and Anton von Leeuwenhoek made to the cell theory (Intro to Cells/ Prokaryotes)
Robert Hooke discovered plant cells. He also saw microbes under a microscope. Leeuwenhoek improved the lenses of microscopes. He found that all organisms are composed of one or more cells.
Describe the important aspects of a properly phrased scientific question. (Nature of Science/ Scientific Method)
Testable/measurable Objective Specific
Know what the atomic number and mass number of an element describes. (Chemistry/ Properties of Water)
The atomic number tells the number of protons, and the mass number tells the numb er of protons and neutrons.
10. Explain the role of antibiotics (such as penicillin and tetracycline) in the microorganisms that produce them. (Intro to Cells/ Prokaryotes)
The role of antibiotics in the microorganisms that produce them is that it allows them to protect themselves as well as outcompete other bacteria for resources.
Describe the properties of water that contribute to earth's suitability for life. (Chemistry/ Properties of Water)
Water allows solutions to be formed. They allow molecules to collide and interact
Describe the relationship between the density of water and temperature and explain how this has impacted the evolution of life on earth. (Chemistry/ Properties of Water)
Water becomes less dense as the heat increases.
20. Fermentation in humans is expensive. Explain. (Cellular Respiration)
We use 6 ATP, however we only produce 4. As a result, we only have a net of -2 ATP.
5. List five structural characteristics common to all cells. (Intro to Cells/ Prokaryotes)
a. Cell Membrane b. Cytoplasm c. Ribosomes d. DNA e. Proteins
7. Describe how each of the following cell types is specialized to perform its task: a.muscle b.liver c.ovary (endocrine) d.macrophage e.sperm (Eukaryotic Cell Structure and Function)
a.Muscle: using protein filaments of actin and myosin that changes both the length and the shape of the cell. b.The SER of muscle cells release calcium that is essential in the contraction and sliding of muscle cells. c.Liver:In liver cells, glucose-6 phosphatase is unique to liver cells and found no where else. You eat glucose so its in the extracellular fluids, it's taken up by the membrane, glucose permease transport glucose across the plasma membrane, in the cytosol, hexokinase attaches a phosphate onto the glucose so that the SER traps it. Glucose-6 could be immediately used to help make ATP, or stack on a glycogen. Only liver cells that have the right proteins in the SER make glucose so that glucose can get back out into the bloodstream. Take glucose out of the blood flow, make into glycogen, get glycogen and make it into glucose and release it back into the blood flow. d.ovary (endocrine): the SER in ovaries and testes release lipid hormones macrophage: cytosol of macrophages can break down and build back up to help the cell maneuver anywhere in the body. e.Sperm: flagella that allows it to travel through the body
12. Contrast allosteric regulation and competitive inhibition and provide a specific example of the former. (Enzymes)
allosteric regulation: is about making an enzyme change shap through another active site while competitive inhibition mimicks the normal substrate and says in the active site blocking the other substrate.
16. Some yeast cells convert pyruvate into alcohol. Describe how this benefits the yeast. (Cellular Respiration)
can survive without oxygen
2. Provide examples catabolic and anabolic pathways in human cells. (Enzymes)
catabolic: digestion anabolic: biosynthesis, the making of DNA or proteins
3. Using the terms oxidation and reduction, summarize the events that occur in the first 3 phases of cell respiration. (Cellular Respiration)
oxidation is used when NADH is converted to NAD+. reduction is used when NAD+ is converted into NADH.
27. Describe the relationship between DNA, RNA and protein. (Molecules of Life)
rna copies dna in order to 'reproduce'.
Provide examples of the role of weak bonds in biological molecules. (Chemistry/ Properties of Water)
weak bonds can become strong when repeated. Hexokinase is an enzyme that catalyzes the first step of cell resp
4. Describe the mechanism by which catalase catalyzes the reaction shown above. (Enzymes)
when a catalase is present the rate of collision is increased, therefore the rate of binding is increased. Has the perfect binding site for the molecules instead of trying go at the right velocity and angle on both molecules.
8. Sketch an enzyme, its substrates and products and illustrate the events that occur over the course of a reaction (binding, catalysis and dissociation). Describe each event. (Enzymes)
when binding the substrates attach to the enzyme and in catalysis the substrates change the enzyme slightly and make new products, in dissociation- the products are spat out
