This preview shows pages 1–3. Sign up to view the full content.
This preview has intentionally blurred sections. Sign up to view the full version.View Full Document
Unformatted text preview: Version 108 EXAM 2 sathasivan (48475) 1 This print-out should have 50 questions. Multiple-choice questions may continue on the next column or page find all choices before answering. 001 2.0 points Which of the following does not contain ac- tive ribosomes that are involved in protein synthesis? 1. a prokaryotic cell 2. a nucleolus correct 3. an animal mitochondrion 4. a chloroplast 5. a plant mitochondrion Explanation: In the nucleolus, ribosomal RNA is synthe- sized but while inside the nucleolus, rRNA is not active and does not take part in protein synthesis. 002 10.0 points Placing a plant cell in a hypotonic solution will cause the cell to 1. burst. 2. swell. correct 3. not change at all. 4. shrivel. 5. divide. Explanation: In hypotonic solutions, there is less solute (and therefore more water) outside the cell; therefore, water will rush into the cell. Plant cells prefer this environment, and use the wa- ter to keep the stem upright and rigid. Unlike animal cells, plant cells have cell walls to pre- vent the cell from bursting. 003 10.0 points The nucleolus of the nucleus is the site of 1. the uncoiling and unraveling of chromo- somes. 2. chromosome replication. 3. ribosome assembly. correct 4. lipid synthesis. 5. protein synthesis. Explanation: Recall 004 2.0 points About how long ago did photosynthetic cyanobacteria originate? 1. 1,500,000,000 years 2. 1,000,000,000 years 3. 2,000,000,000 years 4. 2,500,000,000 years correct 5. 4,500,000,000 years Explanation: 005 2.0 points What is the general name of an enzyme that transfers phosphate groups from ATP to a protein? 1. protease 2. phosphorylase 3. protein kinase correct 4. ATPase 5. phosphatase Explanation: Protein kinase is an enzyme that transfers phosphate groups from ATP to a protein. Version 108 EXAM 2 sathasivan (48475) 2 006 10.0 points Which statement is true about facilitated dif- fusion? 1. Transport proteins are required to move molecules down a concentration gradient. correct 2. Transport proteins and energy are re- quired to move molecules against a concen- tration gradient. 3. Energy is required to move molecules against a concentration gradient. 4. Transport proteins are required to move molecules against a concentration gradient. Explanation: Diffusion refers to molecules moving down a concentration gradient; transport proteins are needed to facilitate, or help, large molecules and charged ions diffuse. Energy is not re- quired in this process. 007 2.0 points Which of the following functions of glycopro- teins and glycolipids of animal cell membranes are most important? 1. maintaining the integrity of a fluid mosaic membrane 2. the ability of cells to recognize like and different cells correct 3. maintaining membrane fluidity at low temperatures 4. assisting the active transport of molecules against their concentration gradients 5. facilitating the diffusion of molecules down their concentration gradients Explanation: Glycoproteins and glycolipids enable cells...
View Full Document
- Fall '10