Biology 12 Name: KEY

Cell Biology Per: Date:

Chapter 3 – Cell Structures & Functions Complete using BC Biology 12, pages 62 - 107

3.1 The Cellular Level of Organization pages 66 - 67

1. The macromolecules, such as carbohydrates and nucleic acids, discussed in the last chapter are not alive, yet the cell is alive. The cell is the structural (a) and functional (b) unit of an organism. It is the smallest unit capable of performing all the functions necessary for life (c)

2. History of microscopy: name the scientist that made the following contributions to cell biology 3. The cell theory is a basic theory of biology which states

All organisms are made up of basic living units called cells

All cells come only from previously existing cells 4. Complete the following table.

Cube side length Surface Area (6s2) Volume (l x w x h) SA:V Ratio

1 cm 6 (12) = 6 13 = 1 6 : 1

2 cm 6 (22) = 24 23 = 8 24 : 8 = 3 : 1

3 cm 6 (32) = 54 33 = 27 54 : 27 = 2 : 1

4 cm 6 (42) = 96 43 = 64 96 : 64 = 1.5 : 1

5. Using the information from the table above, explain why humans are made up of trillions of small cells instead

of just big one. Amount of SA affects the ability to get materials in and out of the cell. Also, larger cells need

more nutrients and produce more wastes BUT have a low SA:V ratio. This is inadequate to sustain the needs of

the cell.

Across

3. Concluded that all cells come from preexisting cells. 5. Made some of the earliest microscopes. Down

1. Stated that plants are composed of cells. 2. Stated that animals are made up of living units called cells. 4. First used the term "cell" to refer to the honeycomb

structure of cork observed in the microscope.

1

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3

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5

V I R

L

C

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S

C

H

L

E

I

D

E

N

O

U

W

W E

S

C

H

W

A

N

N H

H

O

O

K

E

E K

6. Why are there some cells that are much larger, even visible to the human eye, such as a

chicken egg?

These types of cells are not actively metabolizing like other cells. Once fertilized, their

metabolism kicks in and they divide internally into smaller and smaller cells.

7. Give an example of a modification utilized by cells that specialize in absorption.

Columnar epithelial cells along intestine surface are highly folded into microvilli to

increase SA

3.2 Eukaryotic Cells pages 67 - 77

8. All cells are surrounded by a plasma membrane (a) consisting of a phospholipid bilayer (b) embedded with protein (c) molecules.

9. Describe the composition of cytoplasm. Water, salts, dissolved organic molecules 10. Define organelle: Any well-defined subcellular structure that performs a particular function for the cell

11. Identify the organelles on the following diagram. Use Figure 3.3 on page 70 to help.

nucleus vesicle or lysosome

smooth ER

Golgi apparatus

rough ER

plasma membrane cytoplasm ribosome

mitochondria

cytoskeleton

centrosome (or centrioles)

chromatin nucleolus

12. Match the functions of the organelles to their correct descriptions. B cytoskeleton A. cellular respiration (production of energy)

G Golgi apparatus B. shape of cell and movement of its parts

A mitochondria C. lipid synthesis, tasks vary depending on type of cell

J nucleus D. regulates molecule passage into and out of cells

H peroxisomes E. storage of substances

D plasma membrane F. folding, modification, and transport of proteins

I ribosomes G. processing, packaging and distribution of proteins and lipids

F rough endoplasmic reticulum H. various metabolic tasks

C smooth endoplasmic reticulum I. protein synthesis

E vacuoles and vesicles J. storage of genetic information; synthesis of DNA and RNAhe

Cytoskeleton pages 77 - 80

13. Briefly describe the specific parts of the nucleus

chromatin: DNA & associated proteins (“loose” DNA)

chromosomes: condensed DNA (just before cell division)

nucleoplasm: the cytoplasm of the nucleus

nucleolus: rRNA production and formation of ribosome subunits

nuclear envelope: double membrane around nucleus

nuclear pores: allows proteins, ribosome subunits, etc to enter and exit the nucleus

14. Where in the cell are ribosomes found? Floating in cytoplasm (can be polyribosomes) and attached to rough ER

15. The endomembrane system consists of the:

nuclear envelope

endoplasmic reticulum (smooth and rough)

Golgi apparatus

vesicles

16. How does the Golgi apparatus known whether the proteins made at the rough ER belong inside the cell or are

to be transported out of the cell? specific molecular tags like “postal codes”

17. Name three functions of lysosomes. (1) digest materials that

come into the cell (e.g. breakdown polymers) (2) immune

system aid (e.g. destroy pathogens) (3) autodigestion (e.g.

breaking down old or unneeded cell parts)

18. Use Figure 3.7 on page 74 to identify the missing labels in the diagram below.

19. Where in the body do we have cells that contain high numbers of peroxisomes? liver

20. Contrast animal and plant cells (based on organelles or specific organelle functions).

Unique to animal cells

i. lysosomes * cilia & flagella rare for plants

ii. centrosome / centrioles

iii. peroxisomes: break down fat, produce bile salts

Unique to plant cells

i. chloroplasts

ii. cell wall

iii. large central vacuole

21. Plants have chloroplasts (a) which use solar energy to synthesize carbohydrates by

the process of photosynthesis (b). This process is described by the equation:

plasma membrane

incoming vesicle

lysosome

transport vesicle

smooth ER

secretory vesicle

Golgi apparatus

transport vesicle

rough ER

solar energy + CO2 + H2O CH2O + O2

energy + carbon dioxide + water carbohydrates + oxygen KNOW THIS

22. Label the chloroplast below with the terms: grana, stroma, and thylakoid

23. Many organisms carry on cellular respiration (a) which is performed within the mitochondria (b). This process can be represented by the equation:

24. Label the mitochondrion below with the terms: matrix and cristae

25. Compare the chloroplast and the mitochondria in the following table.

Chloroplast Mitochondria A. Organelle with a double membrane X X

B. Converts solar energy into carbohydrates X

C. Converts carbohydrates into ATP X

D. Found in plant cells X X

E. Found in animal cells X

F. Smaller of the two organelles X

G. Contain a single circular DNA molecule and ribosomes X X

H. Divide by splitting in two (similar to how bacteria reproduce) X X

I. Thought to play a role in aging X

J. All come from the female parent X

thylakoid

stroma (fluid)

grana

cristae (folds)

matrix (fluid)

CH2O + O2 CO2 + H2O + chemical energy

carbohydrates + oxygen carbon dioxide + water + ATP KNOW THIS

3.3 The Cytoskeleton pages 77 - 80

26. The cytoskeleton is often compared with the bones (a) and muscles (b) of an animal. However, the cytoskeleton is dynamic (c), especially because its protein components can assemble and disassemble (d) as needed.

27. The cytoskeleton contains three types of proteins. Identify them in the image below.

28. Compare the functions of each of the cytoskeleton components.

Actin filaments (microfilaments): structural role (anchored to plasma membrane by special proteins)

i. Interact with myosin motor molecules

Intermediate filaments: structural role, support nuclear envelope, support plasma membrane, form cell-to-cell junctions, mechanical strength

Microtubules: maintain cell shape, tracks for organelles to move along, form spindle near cell division

i. Interact with kinesin and dynein motor molecules 29. What is the importance of the centrosome to cells? involved in microtubule assembly and disassembly, may

organize mitotic spindle (form the MTOC = microtubule organizing center) 30. Complete the table below. Use Figures 3.13 and 3.14 to help.

Centrioles Cilia & Flagella

Microtubule pattern 9 + 0 9 + 2

Cross-section drawing

Function Aids in cell division Aids in movement

intermediate filaments (width 8-11nm)

microtubules (width 25nm)

actin filaments (width 7nm)

3.4 Plasma Membrane Structure & Function pages 81 - 82

31. Draw a basic cross section of a portion of a plasma membrane. Label the following items: A. carbohydrate chain B. cholesterol C. glycolipid

D. glycoprotein E. hydrophilic head F. hydrophobic tail

G. integral protein H. peripheral protein I. phospholipid

32. Match the following terms and descriptions. D carbohydrate chain A. associated with only one side of the plasma membrane C cholesterol B. span the membrane and can protrude from one or both sides F glycolipid C. regulates the fluidity of the membrane E glycoprotein D. can be attached to either the phospholipid heads or proteins B integral protein E. protein molecule with a carbohydrate chain attached A peripheral protein F. lipid molecule with a carbohydrates chain attached G phospholipid G. primary component of the plasma membrane

33. Describe why the structure of the plasma membrane is

described as a fluid-mosaic model.

“fluid” refers to the phospholipids and the “mosaic” refers to

the proteins that are scattered throughout the membrane

A

B

C D

E

F I

H

G

phospholipid bilayer

34. Identify the FIVE types of integral proteins based on the diagrams below.

3.5 The Permeability of the Plasma Membrane pages 83 - 91

35. Why is the plasma membrane better referred to as selectively permeable rather than semi-permeable? The cell regulates the passage of molecules into and out of cell, “chooses” what goes across rather than allowing through only by size

Type: carrier Function: passage of molecules across membrane, often up a [ ] gradient (requires energy) Example: (1) sodium – potassium pump required for nerve conduction (2) movement of sugars

Type: receptor Function: allows specific molecules to bind causing protein to change shape and resulting in a cellular response Example: insulin receptors in liver causes storage of glucose

Type: cell recognition (also known as glycoprotein) Function: helps the body recognize its own cells versus foreign cells and pathogens (immune) Example: white blood cells keep body healthy

Type: enzymatic Function: carry out metabolic reactions directly (catalyze a specific reaction) Example: adenylate cyclase involved in ATP metabolism. Final steps of aerobic respiration.

Type: channel Function: passage of molecules across a membrane “freely” down a [ ] gradient (no energy) can be gated Example: H+ across inner mitochondria membrane to create ATP

36. Energy is NOT required to transport molecules across the plasma membrane if they are…

small, non-charged

going down [ ] gradient from [high] [low]

Examples include: water, O2, CO2, some sugar and amino acids 37. Energy is required to transport molecules across the plasma membrane if they are…

large, charged

going up [ ] gradient from [low] [high]

Examples include: macromolecules, sodium ions, glucose 38. While both involve movement from [high] to [low], what is the difference between diffusion and osmosis?

Diffusion deals with all ions and molecules while osmosis deals only with water molecules

39. Compare the three states of tonicity that may affect a cell.

Isotonic Hypotonic Hypertonic

Prefix Meaning

the same as

less than more than

Net movement of water (in, out or at equilibrium)

at equilibrium

in out

Drawing of an animal cell in a solution of this type

H2O

H2O

H2O

40. Are the following terms or descriptions related to isotonic (I), hypotonic (HO), or hypertonic (HE) solutions? A. HE crenation B. HO cytolysis C. HO turgor pressure D. HE plasmolysis E. I 0.9% NaCl intravenous drip F. HE preserving meats by salting them G. HO keeping vegetables crisp by spraying them with distilled water

PASSIVE

ACTIVE

41. Biologically useful molecules are able to enter and exit the cell at a rapid rate because of carrier proteins in the membrane. These proteins are believed to undergo a change in shape that moves the molecule across the membrane.

42. Define the two categories of transport

facilitated: no energy required, uses mainly channel proteins and some carrier proteins, requires a [ ] gradient

active: requires energy, gated channel proteins, carrier proteins, formation of vesicles

43. Why are proteins involved in active transport often called “pumps”? because they are pushing ions or molecules UP a [ ] gradient

44. Vesicles must be used to move macromolecules across the plasma membrane. The process of moving large substances out of the cell is called exocytosis (a) while the process of moving substances into the cell is called endocytosis (b).

45. Name the three ways large substances can enter a cell. Then briefly describe the process in terms of an area of the body where it occurs, or what substances are brought in this way, etc.

Description

“cell drinking”

Small items (e.g. glucose) are taken in for use or transport.

Happens continuously for cells (e.g. kidney filtering blood, intestines absorbing

nutrients)

Description

form of pinocytosis

Very selective and more efficient. Uptake and

exchange between cells (e.g. moving substances

between mother and fetal blood at placenta)

Description

“cell eating”

Taking in large particles (e.g. worn out cells or bacterium) into a vesicle to fuse with a

lysosome. Hydrolytic enzymes released to breakdown contents.

Example: white blood cells

phagocytosis pinocytosis receptor mediated endocytosis

Edmodo Assignment! Read “Osmotic Balance in Salmon” article on page 89 and answer the questions below on Edmodo when asked to.

1. Define anadromous and smoltification. 2. Answer book question #2.

3. Describe in moderate detail what happens to a salmon as it returns to its natal stream to spawn.

Chapter 3 Review Questions pages 102 – 107

1. A 3. D 4. D 5. D 6. B 7. C 8. C

9. D 10. B 11. D 12. C 13. D 15. D 16. C

17. A 18. C 19. D 20. C 21. A 22. C 23. A

24. C 25. C 26. C 27. D 28. C 29. D 30. D

31. Only one possible answer for each (a) IV (b) V (c) VII (d) III (e) I (f) V (g) II _

32. (a) VI (b) I (c) II (d) VI (e) V (f) VII (g) IX (h) III, VIII (i) III, VIII (j) IX (k) IX (l) VI (m) IV (n) VII (o) VIII (p) III, VIII

35. cellulose

36. A

37. vesicle

38. maintain rigid structure, pushes against cell wall

40. Name all 3 CO2 + sunlight + H2O

45. Cardiac muscle cells need lots of energy which is supplied by the mitochondria

Testes have smooth ER to produce testosterone

46. H2O2 would build up and be toxic to the cells and body

50. The bacterium would be brought inside a cell by phagocytosis into a vesicle. This would merge with a

lysosome which would empty its digestive enzymes to break it down

51. The cell would shrivel and turgor pressure would decrease

52. Reverse processes: the products of one are the reactants of the other

57. The cell would divide or infold 58. Show your work 3:1 3 ÷ 1 = 3

4:3 4 ÷ 3 = 1.3

3:2 3 ÷ 2 = 1.5 *

60. Water is always entering the cells so organisms need to adapt a method to remove excess water (e.g.

contractile vacuoles, dilute urine, etc)

61. Temperature, molecule size, polarity, [ ]

65. Hypotonic: 1 Hypertonic: 2

66. Chloroplasts pushed to the edges by the central vacuole

67. Water goes out

70. Plasmolysis

71. Water comes in, turgor pressure increases

72. Test tube 1 isotonic Test tube 2 hypertonic Test tube 3 hypotonic

73. Cell shrivels, water goes out, crenation

74. Water goes in, cell bursts, hemolysis

83. 4 and 5

84. about 15%

85. SA:V ratio is too large for efficient exchange of materials for an organism to survive

* incorrect answer key, look at answer for #90

91. Weakened wall gives increased chance for viral infections or cell might burst with increased water intake

Mark the review questions using the answer key on pages 527 – 530

Extra practice (will not be marked). See how many of these organelles you know. Some are duplicated and there may be some that are hard to identify so just name as many as you can.

A – cell membrane

B – nuclear envelope

C – nuclear pore

D – nucleolus

E – chromatin

F – nucleoplasm

G – mitochondria

H – Golgi body

I – centriole

J – microtubules

K - vesicle

L – lysosomes

M – vacuoles

N – actin filaments

O – ribosomes

P – rough & smooth ER

Q – cytoplasm