Category: Cells

THE SURFACE AREA TO VOLUME RATIO OF A CELLINTRODUCTION:

Cells are limited in how large they can be. This is because the surface area and volume ratio does not stay the same as their size increases. Because of this, it is harder for a large cell to pass materials in and out of the membrane, and to move materials through the cell.
In this lab, you will make cube shaped models to represent cells. The dimension along one side will be doubled with each model. You will then calculate the surface area, volume, and the ratio between the two.

MATERIALS:

Scissors
Construction paper
Tape
Metric ruler

PROCEDURE:

1. Construct three cell models like the pattern shown. The dimensions of a side will double each time, with the sides being 2 cm, 4 cm, and 8 cm. Fold and tape into cubes with the tabs to the inside. Record the dimensions in the DATA TABLE (the first one is done for you in the table).

 

CALCULATIONS:

2. Calculate the total surface area for each cell model by the following formula:

surface area = (Length X Width) X 6 sides

 

Record the surface areas in the DATA TABLE.

3. Calculate the volumes for each cell model by the following formula:

volume = length X width X height

 

Record the volumes in the DATA TABLE.

4. Calculate the surface area-to-volume ratio for each cell model by the following formula:

ratio =	surface area volume

 

Record the ratio values in the DATA TABLE.
These ratios show how many times larger the surface area is as compared to the volume. Notice that it becomes less than one very quickly.

QUESTIONS:

1. Which model has the largest surface area?

2. Which model has the largest volume?

3. Which model has the largest ratio?

4. To maintain life, and carry-out cellular functions, materials must be able to move into and out of the cell. Also, material needs to be able to move within the cell. What might be the advantage of having a large surface area?

 

 

5. What might be the disadvantage of having a large volume?

 

 

Section 4-1 Introduction to the Cell

1. What is a cell?

2. Who was the first person to use a simple microscope and view microscopic organisms?

3.. What English scientist was first to view dead plant cells?

4. State the 3 parts to the cell theory.

5. Tell how each of these scientists contributed to the cell theory — Matthias Schleiden, Theodor Schwann, and Rudolf Virchow.

6. Give 3 ways that cells are not alike.

7. What is one of the longest animal cells?

8. Explain why cells are limited in how large they can grow.

9. The shape of a cell reflects its ______________________. Give an example of this.

10. Define organelle & tell what they do for a cell.

11. What surrounds the outside of all cells?

12. Where is the nucleus of a cell & what does it do?

13. What two characteristics do all eukaryotes share?

14. What type of cell is a bacterium?

15. Where is the genetic information (chromosome) of a bacterium found?

16. What are prokaryotes & are they in the same kingdom as eukaryotes?

Section 4-2 Parts of the Eukaryotic Cell

17. Why can cells not survive if they are totally isolated from their environment?

18. What controls what enters or leaves a cell?

19. Define selectively permeable.

20. Describe the phospholipid make up of cell membranes.

21. Cells are bathed in an aqueous environment. What does this mean?

22. Sketch the lipid bilayer of a cell showing the inside & outside of the cell. Be sure to label all parts of the membrane.

23. What is the difference between peripheral & integral proteins in the cell membrane?

24. What is the purpose of the carbohydrate tails attached to some integral proteins?

25. Do all integral proteins look alike? Explain.

26. Explain the fluid mosaic model of the cell membrane.

27. Name 12 organelles found in cells. (See table 4-2)

28. In what part of a cell are organelles found?

29. What is cytosol & what does it contain?

30. Name 3 organelles found in plant, but not animal cells. (See bottom of table 4-2)

31. What is the function of mitochondria? What energy molecule is made there?

32. Why do liver & muscle cells have more mitochondria than other types of cells?

33. Describe the outer covering of the mitochondria.

34. What are cristae & what is their purpose?

35. Mitochondria are able to reproduce inside cells because they have their own ___________.

36. What organelles are the most numerous inside cells?

37. What two things make up ribosomes & are ribosomes surrounded by membrane like other organelles?

38. Ribosomes are made inside the _______________ of a cell.

39. Ribosomes may remain unattached or __________ in cytosol or attach to what other organelle’s surface?

40. What organic compounds to ribosomes synthesize or make?

41. What does ER stand for & what is the ER in a cell?

42. What is the ER’s function?

43. Name the two types of ER inside cells.

44. What is on the surface of rough ER?

45. Rough ER synthesizes large amounts of _________________ for cells.

46. Give 3 functions of smooth ER.

47. What is the Golgi apparatus?

48. Golgi is a system of ________________ or flattened _____________.

49. How does the Golgi work with the endoplasmic reticulum of a cell?

50. What are lysosomes & what do they do?

51. Name 8 things that the enzymes inside lysosomes digest?

52. In what type of cells are lysosomes common? In what type of cell are they rare?

53. Where is the cytoskeleton & what is its function?

54. What are the two major components of the cytoskeleton?

55. How do microfilaments & microtubules differ from each other?

56. What are spindle fibers & what are they made of?

57. What protein makes up microfilaments?

58. Compare cilia & flagella.

59. What is the purpose of the nuclear matrix?

60. What double membrane surrounds the nucleus?

61. Where is chromatin found & what 2 things is it made of?

62. When a cell is ready to divide, chromatin condenses & coils into _____________________.

63. What is the purpose of DNA inside the nucleus?

64. How do nuclear pores help RNA?

65. Where is the nucleolus found and what is made there?

66. Where is the cell wall in plants found, what is its function, and what is it made of?

67. What are the 2 types of cell walls in plants?

68. What is the difference between the primary & secondary cell walls?

69. What is found inside plant vacuoles?

70. What takes up much of the volume of plant cells? What happens to the other organelles?

71. How are plastids similar to mitochondria?

72. What is found inside of plastids?

73. Name the most familiar plastid & tell its function.

74. What are thylakoids?

Section 4-3 Multicellular Organization

75. Cells are organized into ______________________. Give an example.

76. What is an organ & give an example?

77. What forms organ systems?

78. The digestive system is an organ system. Name the organs that make up this system.

79. All the systems working together make up an ______________________ such as a plant or animal.

 

Transport Across Membranes

PowerPoint Questions

Membrane Structure

1. Cell membranes of unicellular organisms are ____________ so the organism can move.

2. What is meant by homeostasis?

3. Homeostasis is also called __________________.

4. How does the plasma membrane help maintain homeostasis?

 

5. Give 7 functions of the plasma membrane.

    a.

    b.

    c.

    d.

    e.

    f.

    g.

6. What is meant by the term selectively permeable?

7. What are cell junctions?

8. Fluid inside the cell is called _________________.

9. Label the plasma membrane (phospholipids, cholesterol, peripheral proteins, integral proteins, cytoskeleton, glcocalyx…)

10. A ________________ bilayer makes up most of the cell membrane.

11. Are phospholipids heads polar or nonpolar? the tails?

12. How many fatty acid chains are in a phospholipid?

13. Describe the heads of a phospholipid.

14. The __________ _____________ ___________ describes the appearance of the cell membrane.

15. Why is the cell membrane said to act like a fluid?

 

16. What causes the mosaic pattern of the cell membrane when viewed from above?

17. The phospholipid ____________ of the cell membrane allows ____________ molecules to pass through easily, but _________________ do NOT.

18. Materials soluble in __________ can pass easily through the cell membrane.

19. Because the cell membrane is ___________________, only ___________ molecules and larger _______________ molecules can move through easily.

20. List 3 substances that pass easily through the cell membrane.

21. _________, _____________ molecules larger than water, and large __________ molecules do NOT move easily through the phospholipids of the cell membrane.

Types of Membrane Transport

22. Simple ____________ requires NO energy to move things across the cell membrane.

23. With simple diffusion, molecules move from an area of ________ concentration to an area of ______ concentration.

24.Why is diffusion considered a passive process?

25. With diffusion, molecules move by their own natural __________ energy or energy of motion.

26.  Explain what happens to a drop of food coloring put into a beaker of water.

 

27. When solutes diffuse through a membrane, they move from __________ to _________ concentration.

28. __________ is the diffusion of _________ across a cell membrane.

29. If water potential is HIGH, solute concentration is __________.

30. If water potential is LOW, solute concentration is ___________.

31. Water moves from _________ water potential to ________ water potential.

32. Water diffuses through the pores called _____________ of the cell membrane.

33. Sketch a picture of a cell in an isotonic environment & show the direction of water movement?

 

 

 

 

34. What is meant by NO NET movement?

35. Sketch a picture of a cell in an Hypotonic environment & show the direction of water movement?

 

 

 

 

36. Sketch a picture of a cell in an hypertonic environment & show the direction of water movement?

 

 

 

 

37. Complete the following table:

38. _____________ occurs whenever water moves out of a cell & the cell shrinks in size.

39. _____________ occurs whenever water moves into the cells causing them to swell and burst.

40. Explain what happens to a red blood cell placed in:

     a. distilled water

     b. a concentrated salt solution

41. Complete the following drawings.

42. Plants prefer ________________ environments, while animal cells do best in _____________ environments.

43. Describe these 3 types of movement across cell membranes.

     a. simple diffusion

 

     b. facilitated diffusion

 

 

    c. active transport

 

44. Passive transport does _______ require additional energy & moves materials from ________ to _________ concentration.

45. Give 2 examples of passive transport in cells.

 

46. ___________ diffusion is a type of __________ transport because energy is NOT required.

47. Facilitated diffusion uses _____________ proteins to help move materials from _________ to __________ concentrations.

48. Name 2 materials that move into or out of cells by facilitated diffusion.

49. name 2 types of transport proteins found in cell membranes.

50. Describe channel proteins.

51. How do carrier proteins help move materials across a cell membrane?

52. Channel proteins have an opening or ___________ through which molecules can passively move by _____________ diffusion.

53. Do all carrier proteins extend across the cell membrane?

54. Explain how these carrier proteins move materials across the membrane.

 

55. Some carrier proteins can change ________ to move materials across the cell membrane.

56. __________ transport requires additional energy to move materials.

57. Active transport uses cellular energy known as _________.

58. Active transport moves materials AGAINST the concentration gradient or from _________ to ___________ concentration.

59. The _______________ pump is an example of active transport.

60. The sodium-potassium pump moves _______ sodium ions out for every ______ potassium ions moved into the cell creating voltage across the cell called the ____________ potential.

61. Moving very large particles out of the cell is called _____________.

62. In exocytosis, wastes are moved out of the cell in ___________ that fuse with the cell membrane.

63. __________ involves moving large particles into the cell.

64. taking in large liquid droplets is called ____________ or “cell drinking”.

65. __________ ____________ endocytosis involves protein ____________ recognizing hormones to help move them into the cell.

66. How does cholesterol get into a cell?

67. “Cell eating” is known as ______________.

68. White blood cells engulfing bacteria is an example of _____________.

69. _____________ is the opposite of exocytosis.

 

 

 

    Construct a 3-dimensional eukaryotic plant or animal cell that includes the organelles listed in the table below. Your cell must show all of the cellular organelles listed on the table. These organelles should be LABELED with straight pin “flags” with the FUNCTION of each organelle written on the back  Make sure that your cell has a FLAT NOT round bottom so it will sit on a table or shelf. 

•  NO FOOD ITEMS MAY BE USED IN THE CONSTRUCTION OF YOUR CELL MODEL! 
•  DO NOT USE CLAY OR PLAY DOUGH AS THE CELL WILL BE TOO HEAVY OR NOT STAY TOGETHER!

ANIMAL CELL

Copyright Pearson Education, Inc.

PLANT CELL

Copyright Pearson Education, Inc.