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Bio 1110
Exam 1
Question | Answer |
---|---|
What is biology? | The study of life |
What is science? | nothing more than a logical inquiry concerning the world (universe) around us |
What are scientific questions? | What, when, where, how, who |
What is NOT a scientific question? | Why |
What type of data is considered in science? | Empirical |
What is empirical data? | Measurable data that constitutes a reasonable explanation for some phenomena |
What are the 5 Characteristics of Life? | Organization, Energy & Metabolism, Homeostasis, Irritability & Adaptation, Reproduction, Growth & Development |
What is organization? | All living organisms consist of at least one cell (basic unit of life) "cell theory" |
What is energy use & metabolism? | Maintain structure by taking up chemicals and energy from the environment |
What is homeostasis? | Maintenance of internal consistency |
What is irritability & adaptation? | Respond to stimuli in the external environment |
What is reproduction, growth & development? | Reproduce and pass on their organization to their offspring |
How is life defined? | Living things are recognized by certain common activities and properties, e.g., order |
What are cells? | The basic structural and functional unit of life |
What is the cell theory? | All life has at least the cellular level of organization. Cells arise from preexisting cells |
Who discovered the cell theory? | Schleiden & Schwann |
What are the two main types of cells? | Prokaryotic and Eukaryotic |
What is DNA? | Heritable information. The continuity of life. Double stranded helix. Codes for tremendous biological diversity & can be copied with great fidelity |
How is DNA organized? | Genes |
How are genes organized? | Chromosomes |
What are the four subunits that make up the double stranded helix? | Adenine (A), Cytosine (C), Thymine (T), Guanine (G) |
Who elucidated the structure of DNA, & when did it happen? | Watson & Crick, 1953 |
What are emergent properties? | Function of a "thing" (e.g., protein, cell, pancreas, digestive system, or rabbit) is the culmination of molecules that are arranged in a specific "order". |
What is reductionism? | Big -> small |
What is the organization of matter in the biosphere? | Subatomic particle, atoms, molecules, macromolecules, cells, tissues, organs, organ systems, organism, population, community, ecosystem, biosphere |
What are chemical reactions in the cell that are regulated? | Enzymes, negative feedback, positive feedback |
What do regulatory mechanisms do? | Allow physiology to be maintained within narrow limits |
Where does energy flow? | Through the ecosystem |
Where do nutrients cycle? | Through the environment |
What is the 1st Law of Thermodynamics? | Energy (matter) CANNOT be destroyed or created, ONLY changed in its form (E=MC^2) |
What is the 2nd Law of Thermodynamics? | All energy (matter) transformations are inefficient (i.e., less than 100%) and some energy is lost as heat. Energy & matter move randomly and from a greater to a lesser concentration |
What are the three domains of life? | Bacteria, archaea, eukarya |
How are organisms cataloged? | Taxonomy |
What is the order of the taxonomic scheme from biggest to smallest? | Domain, Kingdom, Phylum, Class, Order, Family, Genus, Species |
What is evolution? | Theory that gene frequencies change over time. Most important unifying concept in modern biology. Change in a population over time. Speciation. |
How are structure and function related? | Correlated. Form fits function. |
What is discovery science & induction? | Observation of many specifics to generate a generalized conclusion |
What is hypothetic-deductive science? | Begins with a general "idea" and through testing produces specific conclusions |
What is serendipity? | Luck |
What is the scientific method? | 1. Observation 2. Hypothesis 3. Experimentation (repeatable) 4. a) Accept Hypothesis b) Reject Hypothesis 5. a) Theory or Law b) Modify hypothesis; return to step 2 |
What is technology? | The way the average person encounters science. Applies scientific knowledge |
What are the requirements of life? | C, H, O, N, P, S |
What is the atomic number? | The atoms of an element have a particular number of protons. |
What does the atomic number equal? | Number of Protons & Electrons |
What is the mass number? | Number of protons and neutrons in an atom. |
What is mass number a close approximation for? | Atomic Weight |
What are isotopes? | Atoms with different mass numbers. Variations in neutron numbers results. |
What are unstable isotopes? | Radioisotopes. |
How do radioisotopes decay? | By emission of energy and subatomic particles; therefore transforms an isotope into an atom of a different element. |
What are energy shells? | Electrons that occupy space around nucleus |
What are valence electrons? | Electrons in outermost energy shell |
What do valence electrons determine? | Chemical reactivity |
What is a molecule? | Two or more atoms that have come together |
What is a compound? | A molecule that has more than one atomic species |
What are weak bonds? | Electrical forces of attraction. |
What are weak bonds important in? | Proteins |
What are hydrogen bonds? | Fairly weak bond between positively charged Hydrogen atoms and some negatively charged atoms. |
What are hydrogen bonds common in? | DNA |
What are ionic bonds? | Donating electrons. Once an atom "gives" away one of its electrons or accepts one, the atom becomes VERY charged (polar). Many ionic bonds are water soluble? |
What are covalent bonds? | Sharing of electrons |
What is the strongest chemical bond? | Covalent bonds |
What types of bonds do most proteins have in them? | All four chemical bonds: weak, hydrogen, ionic, and covalent |
What happens to ionic bonds in water? | Ionic bonds disassociate in water. |
What are the two types of covalent bonds? | Polar and nonpolar |
What are polar covalent bonds? | Refers to a molecule's tendency to be attracted to water or anything that has an opposite charge (like magnets) |
What are nonpolar covalent bonds? | Refers to a molecule's tendency to be repelled by water or anything that has a charge ( + / - ) |
What are Van der Waals Interactions? | Weak bonds formed when molecules come into close proximity and where the charges of these molecules match (like magnets). |
What type of interaction is common in how enzymes do their "work"? | Van der Waals Interactions |
What is a hydrophobic molecule? | Refers to a molecule or a region of a macromolecules tendency to repel water |
What is a hydrophillic molecule? | Refers to a molecule or a region of a macromolecules tendency to attract water |
What is the "Solvent of Life"? | Water |
What are the properties of water? | Hydrogen bonding, cohesive properties (surface tension), temperature stabilizing effects (evaporation), good solvent for polar or charged substances |
What is cohesion? | The tendency for dissimilar molecules to stick together |
What is adhesion? | The tendency for similar molecules to stick together |
What is a calorie? | The amount of heat needed to raise 1 gram of water 1 degree celcius |
What is a solution with a pH less than 7 classified as? | Acid |
What is a solution with a pH 7 classified as? | Neutral |
What is a solution with a pH greater than 7 classified as? | Base |
What will release free H+ ions when dissolved in water? | Acid |
What will bind to free H+ ions when dissolved in water? | Base |
Why is three-dimensional shape of a molecule important? | Because it is a determinant of its function in a cell |
How is the shape of a molecule determined? | By the arrangement of electron orbitals that are shared by the atoms involved in the bond |
What happens when a covalent bond forms | The orbitals in the valence shell rearrange |
What is a linear molecule? | A molecule with two atoms (shape) |
1 kilogram = ? gram | 1 x 10^3 g |
1 milligram = ? gram | 1 x 10^-3 g |
1 microgram = ? gram | 1 x 10^-6 g |
1 nanogram = ? gram | 1 x 10^-9 g |
1 picogram = ? gram | 1 x 10^-12 g |
1 femtogram = ? gram | 1 x 10^-15 g |
1 attogrom = ? gram | 1 x 10^-18 g |
What are organic compounds? | Compounds of life. |
What do organic compound typically contain? | Carbon and Hydrogen (a few exceptions - carbon dioxide, sodium bicarbonate, carbon monoxide, and a few others which are considered inorganic molecules) |
What are the 4 groups of organic compounds? | 1. Proteins 2. Carbohydrates 3. Lipids 4. Nucleic Acids |
What are the four families of organic molecules? (monomeric form) | 1. simple sugar (monosaccharide) 2. amino acid 3. fatty acid 4. nucleotide |
What are the four families of organic molecules? (polymeric form) | 1. disaccharide, oligosaccharide, polysaccharide 2. protein 3. lipid 4. nucleic acid |
What is synthesis? | Removal of water |
What is condensation? | Removal of water |
What is elongation? | Removal of water |
What is hydrolysis? | Addition of water |
What functions do proteins perform? | Enzymes, carrier molecules, hormones, antibodies, components of the cell well & cell membrane |
What makes up over 50% of a cells dry weight? | Protein |
What is the basic unit molecule of protein? | Amino acids |
What are bonds between amino acids? | Peptide bonds |
What are the parts of an amino acid? | Central carbon, amino group, carboxyl group, hydrogen, *R group (side chain) |
What is the primary level of protein structure? | basic sequence of amino acids |
What is the secondary level of protein structure? | how the primary structure folds back on itself |
What is the tertiary level of protein structure? | how the secondary structure folds back on itself |
What is the quaternary level of protein structure? | intimate interaction of two or more proteins bonding to each other |
What two types of bonds play an important role in protein structure? | Hydrogen bonds and weak bonds |
What determines if proteins will work properly? | If their primary structure is in the correct order of amino acids; if their tertiary and/or quaternary structures are intact. |
What is the activity (function) of a protein based on? | Its structure (3D shape); anything that alters a proteins shape will alter its activity |
How can you alter the shape of a protein (denature)? | heating to 100 degrees celcius, high salt concentrations, reducing agents, etc. |
How is tertiary structure determined? | By a variety of interactions among R groups & between R groups & the polypeptide backbone |
Which interactions between R groups help determine tertiary structure? | Hydrogen bonds, ionic bonds, hydrophobic interactions, and van der waals interactions |
What are disulfide bridges? | Strong covalent bonds that form between sulfhydryl groups (SH) of cysteine monomers which stabilize the structure. |
What is a simple protein? | Contain only amino acids |
What is a conjugated protein? | Contains amino acids and another component: -glycoprotein (addition of sugars) -nucleoprotein (addition of nucleic acids) -lipoprotein (addition of lipids) -phosphoprotein (addition of phosphate groups) |
What elements are in carbohydrates? | C, H, O - ratio of H:O = 2:1 |
What are the functions of carbohydrates? | Fuel for cell activity, food reserve (starch), part of cell wall, part of DNA and RNA (deoxyribose and ribose) |
What are some examples of monosaccharides? | glucose, fructose, galactose |
How many carbons does trioses have? | 3 |
How many carbons does tetroses have? | 4 |
How many carbons does pentoses have? | 5 |
How many carbons does hexoses have? | 6 |
How many carbons does heptoses have? | 7 |
What happens to carbons or aldehyde or ketone group when in an aqueous solution? | React with -OH group, resulting in a ringed structure |
What is an isomer? | Compound that exists in different forms having different arrangement of atoms but the same molecular weight |
What is formed when carbons of the aldehyde or ketone group in the ring form react with -OH group of another monosaccharide? | A disaccharide is formed |
What are polysaccharides? | A chain of monosaccharides |
What are examples of polysaccharides? | 1. glycogen 2. starch 3. cellulose |
What is glycogen? | The storage form of glucose for animales and some bacteria |
What is starch? | The storage form of glucose in plants |
What is cellulose? | The main structural component of plant and algae cell walls |
What are lipids? | Fatty acids; fats and oils |
What do lipids consist of (elements)? | C, H, O - no 2:1 ratio like in carbohydrates |
Are lipids generally polar or nonpolar? | nonpolar |
What is the function of lipids | Food source, energy storage, structure of cell membrane and cell wall |
What is amphipathic | has both hydrophillic and hydrophobic ends. (mostly hydrophobic) |
What is an example of a fatty acid with double bond? | unsaturated hydrocarbons |
What is triglyceride made up of? | 1 glycerol, 3 fatty acids |
What are the two types of fatty acids | saturated & unsaturated |
What happens when phosphate group replaces one of the fatty acids? | Polar head & nonpolar tail form |
What is the main structural component of the cell membrane | Lipids |
What are lipid bilayer membranes | Machines that are held together by weak intermolecular interactions between phosopholipids and other molecules including the proteins |
What are the three components of nucleotides? | 1. nitrogenous base 2. phosphate group 3. five carbon sugar (ribose or deoxyribose) |
What does ATP stand for? | Adenosine triphosphate |
Why are cells so small? | Upper limit on size imposed by surface area to volume ratio Low limit imposed by a need for basic metabolic activities |
What is entropy? | Randomness |
In what domains are Prokaryotic cells found? | Bacteria and Archaea |
In what domain are Eukaryotic cells found? | Eukarya |
What do all cells have? | -Plasma membrane with the main structural feature of a phospholipid bilayer -Cytosol -DNA -Ribosomes |
Ribosomes are responsible for what? | Translation of mRNA to protein |
What are the general features of prokaryotes? | -No membrane bound nucleus -nucleoid -cell wall -peptidoglycan -1 to 10 micrometers in diameter -divide by binary fission (asexual reproduction |
What are the general features of eukaryotes in animals? | -Nucleus -Endoplasmic reticulum (RER & SER) -Golgi -Lysosome -Perioxisome -Mitochondrion -Cytoskeletal elements |
What is the function of the nucleus? | houses DNA and location for DNA & RNA synthesis |
What is binary fission? | Asexual reproduction |
What is the function of the Endoplasmic Reticulum? | Protein synthesis and modification |
What is the function of the Golgi? | Secretion |
What is the function of the lysosome? | Digestive membrane-sac of chemicals |
What is the function of the perioxisome? | Membrane-sac of protective chemicals (e.g., catalase) |
What is the function of the mitochondrion? | Location for the majority of ATP synthesis |
What is the function of the cytoskeletal elements? | Aids in cell structure, hydrostatic pressure, motility of vesicles and cell motility |
What are the general features of eukarotes in plant cells? | -all animal organelles minus flagella & cilia -chloroplast -central vacuole -cell wall |
What is the function of the chloroplast? | Location for photosynthesis |
What is the function of the central vacuole? | Location for food storage |
What is the function of the cell wall? | Polysaccharide layer that give structural support to the cell |
What is the extracellular matrix of an animal cell? | Necessary for attachment & tissue organization (e.g., organs) and cell to cell communication (e.g., immune system) |
What are tight junctions? | Cell to cell junctions that leave no space between cells |
What are desmosomes? | Junctions between cells that are very resistant to physical stress (prevents tearing) |
What are gap junctions? | Regions between cells that allow communicative chemicals to be released and absorbed |
What are plasmodesma? | opening between cells walls allowing the passage of chemicals |
What did Singer-Nicholson create? | Fluid mosaic model (1972) |
What are types of lipid bilayers? | Phospholipids, sterols, glycolipids |
What are types of proteins? | Peripheral, Integral |
Are unsaturated phospholipids fluid or viscous? | Fluid |
Are saturated phospholipids fluid or viscous? | Viscous |
Do membrane proteins move? | Yes |
What are the functions of protein? | Transport, enzymatic activity, signal transduction, intercellular joining, cell-cell recognition, attachment to the cytoskeleton and extracellular matrix (ECM) |
Where are membrane lipids and proteins synthesized? | ER |
Through what do vesicles move? | The Golgi |
What is a selectively permeable membrane? | Only certain chemicals are capable of entering OR leaving a cell due to the hydrophobic & size of the lipid bilayer (cell membrane) |
What is diffusion? | Movement of a molecules/ion/particle from an area of higher concentration to an area of lower concentration |
What is osmosis? | The diffusion of water (greater -> lesser) |
What will a hypotonic solution do to an animal cell? | Make it lysed |
What will a hypotonic solution do to a plant cell? | Normal |
What will an isotonic solution do to an animal cell? | Normal |
What will an isotonic solution do to a plant cell? | Make it flaccid |
What will a hypertonic solution do to an animal cell? | Make it shriveled |
What will a hypertonic solution do to a plant cell? | Make it plasmolyzed |
What is facilitated diffusion? | Movement of solute from an area of higher concentration to lower concentration with the aid of a transport protein |
What does facilitated diffusion require? | Channel or carrier |
What is active transport? | Movement of solute from an area of low concentration to an area of higher concentration |
What does active transport require? | Carrier and energy |
What are types of passive transport? | Diffusion & facilitated diffusion |
What is endocytosis? | Bringing into the cell |
What is phagocytosis? | Engulfing fairly large particles; requires pseudopodia (membrane extensions that surround the engulfed particles) |
WWhat is pseudopodia? | Membrane extensions that surround the engulfed particles |
What is pinocytosis? | Indentation of membrane that surrounds and pinches off within the cell |
What is receptor-mediated endocytosis? | Indentation of membrane due to a signally envent (substrate to ligand binding) that surrounds and pinches off within the cell |
What is exocytosis? | Secreting into the extracellular fluid |
What are types of endocytosis? | phagocytosis, pinocytosis, receptor-mediated endocytosis |
What is the function of intermediate filaments? | provides tensile strength |
What type of cell is the cytoskeleton found in? | Eukaryotic |
What is the function of actin filaments? | Provides strength, & in conjunction with myosin, movement. |
What is the function of microtubules? | Movement of vesicles, maintenance of ER and Golgi organization, movement of chromosomes, formation of cilia and flagella |
What are ribosomes made up of? | Proteins and ribosomal ribonucleic acids (rRNA) |
What organelle does not have a lipid bilayer membrane? | Ribosome |
What is needed to bind together to form a complete and functional ribosome? | 30 S and 50 S |
What type of cell has 70 S? | Prokaryotes |
What type of cell has 80 S? | Eukaryotes |
30 S and 50 S sandwich what? | mRNA |
What type of ribosomes are found in the mitochondrion? | 70 S |
What type of chromosomes are found in the mitochondrion? | Circular |
What is the function of the Mitochondrion? | Location of cellular respiration |
What organelles can replicate on their own? | Mitochondrion & chloroplast |
What type of ribosome is found in the chloroplast? | 70 S |
What type of chromosome is found in the chloroplast? | Circular |
What is the function of the chloroplast? | Location of photosynthesis |
What is the endosymbiotic hypothesis? | Mitochondria and chloroplasts were once free living prokaryotes that were engulfed by Amoeba-like eukaryotic cells |
Stanley Miller experiment tested what? | The Oparin-Haldane theory about the evolution of prebiotic chemicals and the origin of life on earth |
What are meteors? | Bits of comic duct which coalesced into a solid "rock" contain complex molecules like amino acids and sugars |