Biology 101, Exam 2(2021)

Three cell parts found in all cells? correct answer- DNA, plasma membrane, and cytoplasm or ribosomes What is the cell theory? correct answer- The cell is the basic unit of life, all living things are made up of one or more cells, and all cells come from the reproduction of other cells Cells that do not have a nucleus are: correct answer- prokaryotes DNA in bacterial/prokaryotic cells forms a: correct answer- circle DNA in eukaryotic cells are: correct answer- linear Why are cells small? correct answer- Cells do not get very large because the surface area to volume ratio must be high to allow for the ready exchange of materials in and out of the cell What three cell parts are found ONLY in plant cells? correct answer- cell wall, chloroplasts, and the large/central vacuole What is Endosymbiosis? correct answer- The theory that some prokaryotic cells engulfed other prokaryotic cells thus forming membrane-bound structures (like mitochondria or chloroplasts) and ultimately giving rise to eukaryotic cells What is the organelle site of the reaction called CELLULAR RESPIRATION in eukaryotic cells? correct answer- Mitochondria What do you call the site of PROTEIN and LIPID SYNTHESIS in eukaryotic cells is an ENDOMEMBRANE SYSTEM? correct answer- the Endoplasmic Reticulum What can you find in the nucleus? correct answer- the nucleolus and DNA How can you distinguish between the ROUGH E.R. and the SMOOTH E.R.? correct answer- the presence of RIBOSOMES in the rough E.R. What are the three structures that enable cells to move? correct answer- cilia, flagella, and psuedopods What is found within the CHLOROPLASTS and is the site of PHOTOSYNTHESIS? correct answer- thylakoids What are the folds within the MITOCHONDRIA called? correct answer- cristae What are cytoplasmic bridges found between PLANT cells? (holes in the CELL WALL) correct answer- plasmodesmata What are the cytoplasmic bridges found between ANIMAL cells? (openings in the CELL MEMBRANES) correct answer- gap junctions Which organelle contains DIGESTIVE ENZYMES? correct answer- the lysosome The lysosome is produced by the pinching off of portions of the membranes of the: correct answer- Golgi bodies/apparatus What is the site of PROTEIN SYNTHESIS? correct answer- Ribosomes What is the largest CYTOSKELETON component? correct answer- the microtubules What are the structures involved in CELL MOVEMENT that are made up of "9+2" microtubules? correct answer- Cilia and Flagella What are the pair of structures that are made up of 9 triplets of microtubules? correct answer- the centrioles Centrioles are involved in the movement of chromosomes during cell division and found only in: correct answer- Animal cells Describe the make-up of a CELL MEMBRANE correct answer- The cell membrane is made of a bilayer of PHOSPHOLIPIDS, with PROTEINS floating in them Describe a PHOSPHOLIPID correct answer- The hydrophilic PHOSPHATE HEADS face outward while the hydrophobic FATTY ACID TAILS face inward What is the simplest type of passive transport across the membrane? What does it do? correct answer- diffusion it allows the passage of non polar molecules across phospholipids What are two non polar molecules that pass across phospholipids? correct answer- Carbon DiOxide (CO2) and Oxygen (O2) If a protein is involved in passive transport across the membrane then the process is called: correct answer- facilitated diffusion If molecules taken into the cell go from a Low concentration of that substance outside the cell to a High concentration ([L] to [H]) inside the cell through a carrier protein, then what is the process called? And what does it need for energy? correct answer- It is called ACTIVE transport and needs ATP for energy What happens if a red blood cell is put in a HYPOtonic solution? correct answer- it will swell up and burst What happens if a red blood cell is put in a HYPERtonic solution? correct answer- it will shrivel (plasmolysis) What happens if a plant cell is put in a HYPOtonic solution? correct answer- it will become rigid since the central vacuole creates TURGOR PRESSURE pushing against the cell wall which prevents wilting What are two examples of ENDOCYTOSIS? What do they do? What do they require? correct answer- 1. Phagocytosis (which means "cell eating") takes in LARGE molecules or cells 2. Pinocytosis (which means "cell drinking") takes in SMALL particles dissolved in fluid BOTH require ATP Glucose enters the cell through what process? Why? correct answer- Glucose enters the cell through the process of FACILITATED diffusion since it uses carrier proteins and does not require energy input (passive transport) Carbon DiOxide (CO2) and Oxygen (O2) enters the cell through the phospholipid bilayer by what process? Why? correct answer- They enter through the process of SIMPLE diffusion since they are non polar and do not require energy input (passive transport) How does water enter the cell, and by what process? correct answer- Water enters the cell through PROTEINS in the membrane called AQUAPORINS by the process of OSMOSIS which does not require energy input (passive transport) What does ACTIVE transport require? correct answer- ATP What is established by a positive charge on the outside of a nerve cell membrane? correct answer- the sodium-potassium pump (Na-K) What are enzymes and what are their functions? correct answer- Enzymes are CATALYSTS that speed up chemical reactions If energy is stored in the product of a reaction, the chemical reaction is: correct answer- Endergonic What does the SUBSTRATE bind to on an ENZYME? correct answer- the active site Name 3 factors that effect the function of enzymes: correct answer- 1. Temperature 2. pH 3. Salinity (also inhibitors) The enzyme shape changes very slightly once the enzyme and substrate bind together. What is this called? correct answer- Induced fit What is the first law of thermodynamics? correct answer- Energy is neither created nor destroyed, it just changes form What is the second law of thermodynamics? correct answer- The disorder (entropy) of a system INCREASES with time. For living systems to MAINTAIN ORDERLINESS, they must INput energy from their environment What kind of energy does Sucrose have? And where is it stored? correct answer- Sucrose has POTENTIAL energy, and this energy is stored in the CHEMICAL BONDS What is the cell's currency? (energy readily available to cells) correct answer- ATP ATP is made by all cells by what process? correct answer- Cellular respiration ATP supplies energy by giving up what? correct answer- phosphate groups What is an organic catalyst, and what is its function? correct answer- enzymes. enzymes react with a specific substrate in an active site What are enzymes made of? correct answer- amino acids (proteins) Why are enzymes effective in SMALL quantities? correct answer- Enzymes are used over an over again because they are not changed or altered during the reaction Describe an allosteric enzyme: correct answer- an allosteric enzyme has ONE active site for its specific substrate and ANOTHER site that binds with an inhibitor molecule (also called non-competitive inhibition) What 4 things have an effect on enzyme activity? (by altering the shape of the active site) correct answer- 1. Temperature 2. pH 3. Feedback inhibition 4. Chemicals that fit into allosteric sites One of the main functions of an enzyme is to ___ so that the reaction can ___ correct answer- One of the main functions of an enzyme is to LOWER THE ACTIVATION ENERGY so that the reaction can OCCUR AT BODY TEMPERATURE Describe a cofactor: correct answer- Certain METAL IONS and COENZYMES called COFACTORS are needed for some enzymes to function. An example is the IRON ION. (which is necessary for the enzyme hemoglobin to accept O2) Describe simple diffusion: correct answer- Moves WITH the concentration gradient ([H] to [L]). No energy is required. Some structures involved are a FATTY ACID BILAYER. Some examples of the substances transported are GASES (O2 and CO2) and FATTY ACIDS. Describe facilitated diffusion: correct answer- Moves WITH the concentration gradient ([H] to [L]). No energy is required. Some structures involved are PROTEIN CARRIERS in the fatty acid bilayer. Some examples of the substances transported are GLUCOSE and AMINO ACIDS. Describe active transport: correct answer- Moves AGAINST the concentration gradient ([L] to [H]). ATP is required. Some structures involved are the PROTEIN PUMP in the fatty acid bilayer. Some examples of the substances transported are the Sodium-Potassium (Na+ K+) pump and the Chlorine (Cl-) ion channel. Describe endocytosis: correct answer- Moves AGAINST the concentration gradient ([L] to [H]). ATP is required. Some structures involved are PROTEINS and FATTY ACIDS (pseudopods for phagocytosis). Some examples of the substances transported are BACTERIA and LARGE MOLECULES like Insulin. Describe exocytosis: correct answer- Moves AGAINST the concentration gradient ([L] to [H]). ATP is required. Some structures involved are PROTEINS and FATTY ACIDS. Some examples of the substances transported are LARGE MOLECULES like Insulin. Describe osmosis correct answer- Moves WITH the concentration gradient ([H] to [L]). No energy is required. Some structures involved are AQUAPORINS between fatty acids. OCCURS IN WATER ONLY. What is the first stage of cellular respiration? (the oxidation of glucose) correct answer- glycolysis Where does glycolysis take place? correct answer- the cytoplasm Glucose in glycolysis produces two 3-Carbon molecules called: correct answer- pyruvates (pyruvic acid) Does glycolysis require oxygen? correct answer- No In order for pyruvate to enter the mitochondria, what must be present? correct answer- oxygen The second stage of cellular respiration is the oxidation of: correct answer- pyruvates The oxidation of pyruvates results in the production of a 2-Carbon molecule called: correct answer- acetyl Acetyl combines with: correct answer- coenzyme A The third stage of cellular respiration is: correct answer- the Kreb's cycle How many times does the Kreb's cycle turn to make one glucose? correct answer- two times The fourth stage of cellular respiration is: correct answer- the Electron Transport Chain (ETC) Where does the Electron Transport Chain take place? correct answer- the cristae (of the mitochondria) What is established in the inter-membrane space while the electrons are passed down the Electron Transport Chain, which FUEL the pumping of ions across the membrane? correct answer- The Proton (H+) Gradient The protons (H+) diffuse through the ___ enzyme to produce ATP correct answer- ATP Synthase For each molecule of NADH, how many ATP's are produced? correct answer- three ATP's For each molecule of FADH, how many ATP's are produced? correct answer- two ATP's The ANAEROBIC stage of cellular respiration is called: correct answer- Glycolysis If oxygen is absent, then the resulting pyruvate is converted to what? correct answer- Lactic Acid (Lactate) in animals and ethanol in yeast The conversion of a pyruvate to ethyl alcohol is a process called: correct answer- fermentation Fermentation is a form of ___ respiration correct answer- Anaerobic Anaerobic respiration/Glycolysis occurs in what organelle? correct answer- The cytoplasm Yeast is used to rise dough since it produces the gas: correct answer- Carbon DiOxide (CO2) Aerobic respiration formula: correct answer- Glucose (C6H12O6) + 6 Oxygen (6(O2) - to- 36-38 ATP + 6 Water(6(H2O) + 6 Carbon DiOxide (6(CO2) occurs in mitochondria Anaerobic respiration in animals formula: correct answer- Glucose (C6H12O6) -to- 2 ATP + 2 Lactic Acid occurs in cytoplasm Anaerobic respiration in yeast formula: correct answer- Glucose (C6H12O6) -to- 2 ATP + 2 Carbon DiOxide (2(CO2) + 2 ethanol occurs in cytoplasm Photosynthesis formula: correct answer- 12 Water (12(H2O) + 6 Carbon DiOxide (6(CO2) -to- Glucose (C6H12O6) + 6 Oxygen (6(O2) + 6 Water (6(H2O) With light and chloroplasts Cellular respiration formula: correct answer- Glucose (C6H12O6) + 6 Oxygen (6(O2) - to- 36 ATP + 6 Water (6(H2O) + 6 Carbon DiOxide (6(CO2) With enzymes and mitochondria The energy found in glucose originates from what? correct answer- the sun The organelle needed to produce glucose is ___? In what process? correct answer- The chloroplasts produce glucose in the process of photosynthesis The organelle needed to break down glucose is ___? In what process? correct answer- The mitochondria breaks down glucose in the process of cellular respiration Where can you find cellulose? correct answer- the cell walls Cellulose is made up of: correct answer- glucose molecules What is the name of organisms that do not obtain their energy from the sun but from GEOTHERMAL energy or from CHEMICALS? correct answer- Chemotrophs Name the two raw materials needed for photosynthesis: correct answer- Water (H2O) and Carbon DiOxide (CO2) The best color lights for plant growth are: correct answer- red and blue Carbon enters the ecosystem via the molecule called ___? During what process? correct answer- Carbon DiOxide (CO2) during the process of photosynthesis The Light Dependant Reaction occurs in which organelle? correct answer- The thylakoid membrane The Light Independent Reaction occurs in which organelle? correct answer- The stroma (fluid) in the chloroplasts Describe the first stage of photosynthesis: correct answer- It begins when an electron in the Chlorophyll A molecule is excited by a PHOTON of light in Photosystem II (p680). This results in the splitting of WATER and the release of OXYGEN through the STOMATES of the leaf. Describe how ATP is produced: correct answer- In order for ATP to be produced, a PROTON GRADIENT must be established in the compartment of the mitochondria as electrons pass down the ELECTRON TRANSPORT CHAIN. The gradient provides the energy as the ions are pumped through the ATP SYNTHASE ENZYME for a phosphate to be added to ADP to become ATP. What can you find inside the THYLAKOID MEMBRANE that passes electrons from Photosystem II to Photosystem 1? correct answer- Cytochrome proteins Describe the formation of NADPH: correct answer- The electrons excited from the CHLOROPHYLL A (p700) in Photosystem I and the HYDROGEN pumped through the membrane are ultimately accepted by NADP+ to form NADPH What are the final products of the Light Dependant reaction? correct answer- ATP and NADPH The Light Independent reaction uses ATP and NADPH to run the Calvin Cycle to produce what? correct answer- 2 P Gal's or 1 Glucose The Light Independent reaction fixes Carbon DiOxide (CO2) to a 5-Carbon molecule called ___ with the enzyme ___. correct answer- the 5-Carbon molecule is called RuBP with the enzyme Rubisco. The first 3-Carbon product produced in the Light Independent reaction is: correct answer- PGA How many P Gal's make one Glucose? correct answer- Two P Gal's make one Glucose What happens to the remaining P Gal's produced in the Calvin cycle? correct answer- The remaining P Gal's are converted back to the Carbon DiOxide acceptor called RuBP, and the cycle repeats In order to survive hot dry environments, plants evolved a different pathway to fix Carbon DiOxide called the...? correct answer- C4 Pathway In C3 plants, if Oxygen (O2) competes with Carbon DiOxide (CO2) for the active site of the enzyme Rubisco, then glucose is not produced, resulting in the death of the plant. What is this process called? correct answer- Photorespiration Pineapples and cacti are examples of plants that close their stomates during the day and carry out the Light Independent Calvin Cycle reaction during the night. What is this process called? correct answer- The Cam Pathway