Figure 1. Base your answer to the question on the information and diagram below and on your knowledge of biology.

Transcription

1 Name: Teacher: Lathrop Topic 3 cells CR HW #3 Figure 1 Base your answer to the question on the information and diagram below and on your knowledge of biology. Using a microscope and a wet-mount slide, a student observed a pond water sample containing paramecia, which are singlecelled freshwater organisms. He noticed that there was a structure within each living paramecium that contracted regularly about four times each minute. He researched the organism in his science textbook and found that the structure was a contractile vacuole and its function was to remove excess water from the paramecium. In the diagram below, a paramecium is represented as seen through a microscope. The function of the contractile vacuole is described. He decided to determine if the concentration of salt in the environment of the paramecium would affect the rate at which the contractile vacuole would contract. 1. [Refer to figure 1] The student predicted that the contractile vacuole would contract fewer times in one minute in a solution that had a higher concentration of salt than that found in typical pond water. This prediction is most likely 1. correct, because a high concentration of salt in the environment will force water into the cell, causing the contractile vacuole to pump 2. incorrect, because salt would be entering the cell, and the contractile vacuole would have to pump it out 3. incorrect, because the concentration of salt in the environment should not affect a cell 4. correct, because water would be moving out of the cell into the salt solution 2. [Refer to figure 1] The process used to remove excess water from the paramecium by the contractile vacuole is 1. synthesis 3. active transport 2. digestion 4. passive transport

2 3. The diagram below represents two cells viewed using the same magnification with the same microscope. One possible conclusion that can be drawn about the activity of these two cells is that 1. more active transport occurs in cell B than in cell A 2. more active transport occurs in cell A than in cell B 3. cell B uses some of the extra mitochondria to make food 4. cell A is a plant cell since it has a cell wall 4. Structures in an animal cell are represented in the diagram below. Which row in the chart correctly identifies the functions of structures A, B, and C? Row Structure A Structure B Structure C 1. waste removal extract energy from nutrients protein synthesis 2. information storage transport of materials storage of liquids 3. protein synthesis storage of wastes reproduction 4. cell communication transport of materials waste removal

3 5. The diagram below represents a cell and some molecules in its environment. Which molecule would require the use of energy in order to be brought into the cell? The diagram below represents what occurred when an onion cell and a red blood cell were placed in distilled water. The best explanation for why the onion cells do not burst, while red blood cells often do, is that 1. the red blood cells have only a cell membrane, which does not protect them from bursting 2. the onion cells do not have a cell wall that could protect them from bursting 3. the onion cells have a cell membrane, which can protect them from bursting 4. the red blood cells have a cell wall, which does not protect them from bursting

4 7. A cell is represented in the diagram below. The coded information that the cell uses to synthesize many different proteins is stored in structure 1.A 3.C 2.B 4.D 8. State one reason why a molecule may not be able to pass into or out of a cell.

5 9. The diagram below represents a laboratory setup used to demonstrate the movement of molecules across a selectively permeable membrane. In the diagram below, draw the 5 starch and the 12 glucose molecules to show where they would most likely be located after 15 minutes.

6 10. A laboratory setup using an artificial cell made from dialysis tubing is shown in the diagram below. Identify the process that would most likely be responsible for the movement of glucose from inside the artificial cell to the solution outside of the cell. Figure 2 Base your answer to the question on the diagram of a cell below. 11. [Refer to figure 2] Describe how structures 1 and 2 interact in the process of protein synthesis.

7 Figure 3 Base your answer to the question on the diagram below, which shows some of the specialized organelles in a single-celled organism, and on your knowledge of biology. 12. [Refer to figure 3] State the name of the organelle identified by label D. Explain how the function of organelle D assists in the maintenance of homeostasis. Identify a system in the human body that performs a function similar to that of organelle D.

8 Answer Key for Topic 3 Cells CR HW # Allow credit for a response showing the five starch molecules only on the left side and glucose molecules distributed on both sides. Example: Note: The number of glucose molecules on each side does not have to be equal diffusion or passive transport Acceptable responses include, but are not limited to: Structure 2 provides the code for assembling protein at structure 1. DNA in the structure 2 provides the code for assembling proteins at the ribosome Structure 2 provides the code for assembling amino acids into proteins at structure 1 RNA made in structure 2 goes to structure 1 so proteins can be made Acceptable responses include, but are not limited to: too large to pass through the cell membrane no receptor site faulty receptor site molecule is charged 12. The name of the organelle is cell membrane. How the organelle assists in the maintenance of homeostasis: The cell membrane controls the movement of molecules into and out of the cell. A system in the human body that performs a function similar: excretory system, lining of digestive system (or respiratory system).