Meizoso Biology MIDTERM Review QUESTION WITH ANSWERS NAME_______________________________________________________ Goal 1: Learner will develop abilities necessary to do and understand scientific inquiry. 1.01 Identify biological problems and questions that can be answered through scientific investigations. KNOW your scentisits. 1.02 Design and conduct scientific investigations to answer biological questions (create testable hypotheses, identify variables, use a control or comparison group when appropriate, select and use appropriate measurement tools, collect and record data, organize data into charts and graphs, analyze and interpret data, communicate findings). What is the independent variable? The dependent variable? Temperature Breathing rate What is the best type of graph for this data? Why? Line (each point has two numbers) What happens to breathing rate with increase in Temp? Breathing rate increases What would be a good control for this experiment? Measure breathing rate of fish in regular environment How do you think the breathing rate was measured? Counting movements of gill cover or mouth openings What do you think would happen if you raised the temperature even more? Fish might die at some point – living systems cannot handle too much increase in T. Why would it be a bad idea to do this? Death of fish Goal 2: develop an understanding of the physical, chemical and cellular basis of life. 2.01 Compare and contrast the structure and functions of the following organic molecules: Macromolecules Function Subunits Carbohydrates Quick energy; plant cell walls Monosaccharides such as glucose Proteins Serve as enzymes, antibodies, plasma membrane Amino acids inclusions; carrier molecules (hemoglobin); structural Lipids Long term energy storage, insulation, plasma membranes Glycerol and 3 fatty acids Nucleotides (sugar, Nucleic Acids Carry instructions for making proteins; also carry those phosphate, Nit. base) instructions to the ribosomes Specific Molecule Starch carbohydrate Cellulose carbohydrate Insulin protein Glycogen carbohydrate Glucose carbohydrate Enzymes Function Plants store glucose as starch – source of energy Subunits glucose Form the cell walls of plants glucose Used to help store glucose in liver as glycogen Amino acids Animals store glucose as glycogen – source of energy Glucose Simple sugar used in cellular respiration (aerobic and anaerobic); energy is released Catalysts for chemical reactions (both synthesis and Amino acids 1 Meizoso Biology MIDTERM Review QUESTION WITH ANSWERS protein decomposition) Hemoglobin Oxygen carrier molecule found in the blood protein Fats Used for long term energy storage and insulation – as well lipids as forming cell membranes DNA Found in nucleus – carries instructions for making Nucleic acid proteins RNA Form the ribosomes, forms mRNA to carry genetic info to Nucleic acid ribosome, forms tRNA which carry amino acids to ribo. Describe the following nutrient tests: Amino acids Glycogen and fatty acids nucleotides nucleotides Nutrient Starch Type of Test For presence of starch Negative Test Stays brownish gold Positive Test Turns blue black Lipids Brown paper bag No greasy mark Has a greasy mark Monosaccharides Benedict’s Test Stays turquoise blue Protein Biuret’s test Turns brick red (orange) Turns pinkish violet Stays deep purplish blue Explain the importance of shape to enzyme function. Enzymes function by lock and key – each enzyme has to fit the molecules that it joins together or breaks apart; if it does not fit, it cannot function. Explain what determines the shape of an enzyme. The order of the amino acids determines the secondary and tertiary levels of structure. Explain why enzymes are specific. The specific substrate of an enzyme has the same shape as the active site on the enzyme. The substrate and enzyme fit together like a lock and key. 2.02 Investigate and describe the structure and function of cells including cell organelles, cell specialization, and communication among cells within an organism. Fill in this chart. Also give the letter or number of the part as seen in the diagrams below. Cell Part and Letter Structure Description Function Nucleus Porous nuclear envelope; contains Carries code for what proteins to A, 6 chromosomes (DNA) and nucleolus make (inherited information) Plasma Membrane Phospholipid bilayer with embedded Regulates what leaves and enters K, near 11 proteins, etc. cell Cell wall Composed of cellulose; surrounds Gives structure to plant cells PLANTS only J plasma membrane Mitochondria Two membrane layers; inner membrane Where parts of aerobic cellular L, 1 folded to incr. surface area respiration takes place Vacuoles G, 3 Membrane bound sacs Sacs -hold food or water; in animals, Large in PLANTS small vesicles hold materials Chloroplasts I Structures containing stroma and grana Site of photosynthesis PLANTS only Ribosomes Small beads of RNA found on ER or in Site of protein synthesis (“read” the F, 13 cytoplasm code found on mRNA) Which cell is the plant cell (left or right)? (LEFT) Which structures are found only in the plant cell? Chloroplast, cell wall, large central water vacuole Which structures are found only in the animal cell? Centriole (#2) 2 Meizoso Biology MIDTERM Review QUESTION WITH ANSWERS Know all the parts of the Microscope: Put the following steps for making a wet mount slide in order. A. Once the object is located, without moving the adjustment, change to medium power B. Put the tissue on the slide C. Switch to high power and bring the object into clear focus again. D. Add a coverslip E. Place the slide on the stage of the microscope F. Add a drop of water G. Try to locate the object using low power and coarse adjustment H. Use fine adjustment to bring the object into clear focus. 1) ___B__ 2) __F___ 3) __D ___ 4) _ E ____ 5) __G___ 6) __A___ 7) __H___ 8) _C____ How do you determine total magnification of a microscope? (Assume the eyepiece magnifies 10 x and the objective magnifies 40 x) 10 times 40 = 400x Draw how the letter “e” would look as view through a microscope? Upside down and reversed left to right Put the following in order from smallest to largest: Organ systems __cells_____ Cells _tissues___ Organs _organs____ Tissues ___organ systems__ Explain what has happened in the diagram to the left. Water passed to right; starch could not move through membrane – too large. Why did the large dark molecules NOT move to the left? Too large for membrane pores How is the semipermeable membrane like a cell membrane? Cell membranes have pores that selectively move materials in and out. If the dark molecule is starch, where is the starch concentration greatest (left or right)? If the white molecule is water, where is the water concentration greatest at first? On left In osmosis, water moves from an area of __high________ to an area of ______low___ concentration. 3 Meizoso Biology MIDTERM Review QUESTION WITH ANSWERS If the dark molecules could move, in what direction would they move? From right to left Why? High concentration is on right; low is on left and molecules move from high to low concentration. In diffusion, molecules move from an area of ___high_____ to an area of __low______ concentration. What is osmotic pressure? The difference between concentrations of molecules on each side of membrane – greater the difference, the greater the osmotic pressure. Draw arrows to show which way water will move in each of the following situations: a. Salt inside the cell = 65% and outside the cell 40%. ----------------------------------------- (water moves into cell) b. Sugar inside the cell 27% and outside 80%. --------------------(water moves out of cell) What is homeostasis? Regulation of internal environment; maintenance of balance and stability How do cells maintain homeostasis: Consider pH, temperature, blood glucose, water balance (negative feedback of hormone systems maintains homeostasis); insulin and glucagon work together to maintain blood sugar; osmosis regulates water; temperature regulation through sweating, shivering, blood vessels opening wide and becoming smaller; pH through buffers and H ions. Comparison of active and passive transport Requires energy? Low to high concentration or high to low concentration? Examples PASSIVE TRANPORT NO ACTIVE TRANSPORT YES High to Low with concentration gradient Osmosis of water; movement of glucose Low to High against concentration gradient Neurons – sodium/potassium pumps or iodine in thyroid Energy Use the following diagram to show where energy is released and where energy is used. Also use arrows on the lines attached to the circles to indicate the direction of the energy. What cellular process produces ATP? Cellular respiration What is ATP energy used for? Give examples. To provide energy for all cell processes that require energy – active transport for example. 2.05 Investigate and analyze the bioenergetic reactions: aerobic respiration, anaerobic respiration, and photosynthesis. Label the following molecules in these equations (water, glucose, oxygen, carbon dioxide, ethyl alcohol) A) water + carbon dioxide = glucose + oxygen gas (Photosynthesis) B) glucose + oxygen gas = carbon dioxide + water ( Aerobic Cellular Respiration) C) glucose = ethyl alcohol + carbon dioxide (Fermentation; anaerobic cellular respiration) A) B) C) Which of the above reactions is photosynthesis? A 4 Meizoso Biology MIDTERM Review QUESTION WITH ANSWERS Which of the above reactions is fermentation (anaerobic cellular respiration)? C Which of the above reactions is cellular respiration (aerobic)? B Which reaction(s) requires or stores energy? A Which reaction(s) release energy (ATP)? B and C Which reaction releases the most energy? B Why? Oxygen allows complete breakdown of glucose Which reaction requires chlorophyll? A What is the purpose of the chlorophyll? Trap sun’s energy Which reaction requires light? A What is the light used for? Provides radiant energy which is stored as chemical energy in glucose Which organisms carry out process A? plants and algae (photosynthetic protists) Which organisms carry out process B? all organisms except anaerobes Which organisms carry out process C? anaerobes (bacteria) and yeast Which process uses chloroplasts in eukaryotes? Photosynthesis Which process uses mitochondria in eukaryotes? Aerobic Cellular Respiration What factors could speed up (or slow down) process A? amount of light, water, carbon dioxide; temperature; pH What factors could speed up (or slow down) process B? amount of glucose; amount of oxygen; temperature; pH What factors could speed up (or slow down) process C? amount of glucose; temperature; pH 2.04 Investigate and describe the structure and function of enzymes and explain their importance in biological systems. What is the function of enzymes in biological systems? Why are they necessary for all biochemical reactions? To speed up the combining or break down of substances; the reactions would be too slow to be compatible with life. Explain why enzymes can be reused over and over again. Not changed by the reactions that they catalyze. Why is there only one kind of enzyme for each biochemical reaction? Enzymes function by shape (lock and key) so there is just one enzyme for each type of reaction. How do extreme pH and extreme temperature affect enzymes? Extremes in pH or temperature can alter the secondary and tertiary bonds of a protein; altered shape means altered function. The enzyme is denatured. Explain the lock-and-key model of enzymes and substrates. The substrate fits the enzyme like a lock fits a key; there is an active site where the substrate fits into the enzyme. 5