1. Cell Structure and Function
Chapter 7
Cell Structure and Function

2. The History of the Cell Theory and Microscopes
Section 7-1
The History of the Cell Theory and Microscopes

3. Historical View of the Cell Theory
As science improves, so do improvements in scientific instruments, and improved scientific instruments lead to new discoveries.

4. 1590 – Zacharias Janssen
Built first simple microscope (one set of lenses)

5. 1670’s Anton Van Leeuwenhoek
Made improvements
270x magnification
Saw bacteria, protozoa, sperm cells, red blood cells and yeast cells

6. 1665 – Robert Hooke Produced a compound microscope
Saw hollow boxes and named them “cells”

7. 1665 – Robert Hooke

8. 1831 – Robert Brown
Saw central structure in plant cells, called this structure a nucleus

9. 1838 – Theodore Schwann
Concluded that all animals are made of cells

10. 1838 – Matthias Schleiden
Concluded that all plants are made of cells

11. 1839 – Johannes Purkinje
Stated that “the cell is the unit of function of life”

12. 1858 – Rudolf Virchow
Concluded that “ cells come only from previously existing cells”

13. The Cell Theory All living things are composed of cells
Cells are the basic units of structure and function
New cells are produced from existing cells

14. Prokaryotes and Eukaryotes
Section 3-2
Prokaryotes and Eukaryotes

15. Eukaryotes
Have a nucleus and membrane covered organelles

16. Prokaryotes
Don’t have a nucleus and membrane covered organelles

18. Eukaryotic Cell Structures

19. Plasma Membrane Separates the cell from its environment
Controls the transport of materials in and out
Allows some materials but not others to pass through this is called…
Selectively permeable

21. Endoplasmic Reticulum
Extensive network of tube-like structures that forms a passageway that functions in the transport of materials throughout the cells

23. Ribosomes Site of protein synthesis
Attached to the walls of the ER or move freely in the cytoplasm

24. Golgi Bodies Stack of tiny, flattened sac-like tubes used in secretion
Package protein molecules in a membrane and send the package to the cells surface

26. Mitochondria Where cellular respiration takes place to release energy
“Mighty Mitochondria”
Powerhouse of the cell

28. Microtubules
Tubes that serve as support for the cell

30. Microfilaments
Thin threads attached to the cell membranes, play a role in movement

32. Lysosomes Vesicles that contain enzymes used in digestion
Fuses with food vacuoles to digest food into smaller pieces
Digest old cell structures to dispose of them or even entire cells

35. Nucleus
Regulates all the cells activities

37. Chromosomes Long coiled fibers that carry the material of heredity
Made of protein and DNA

39. Nucleolus Composed of RNA
Involved in the passage of RNA into the cytoplasm

40. Centrioles
Small cylinders in the cytoplasm that play a role in cell division

42. Cilia

44. Flagella

46. Chloroplasts
Organelle found only in plants, used to make food

48. Vacuoles Spherical, bubble-like storage sacs
Plant cells have very large vacuoles compared to animal cells

49. Cell Wall Rigid structure that surrounds the cell membrane
Made of cellulose
Permits most things to pass through
Cell Wall

50. Section 3-3
Cellular Processes

51. The Big Idea
Cells need to regulate the movement of dissolved molecules on either side of the membrane

52. Cell membrane
Regulates what enters and leaves the cell and also provides protection and support
Outside
of cell
Inside
(cytoplasm)
Cell
membrane
Proteins
Protein
channel
Lipid bilayer
Carbohydrate
chains

53. Cell membrane Made of a double layered sheet called a lipid bilayer
Outside
of cell
Inside
(cytoplasm)
Cell
membrane
Proteins
Protein
channel
Lipid bilayer
Carbohydrate
chains

54. Cell Wall Provide support and protection for cell
Found in more than just plants
Contrary to popular belief, not selectively permeable

55. Cell Walls

56. Diffusion Through Cell Boundaries
One of the more important functions of the cell membrane is to regulate the movement of dissolved molecules from one side of a membrane to the other

57. Concentration The mass of solute in a given volume of solution
Mass/volume

58. What is the concentration of 12 grams of salt in 3 liters of water?

59. In a solution, particles move constantly

60. Diffusion
Process by which molecules of a substance move from areas of high concentration to areas of low concentration

61. Diffusion

62. Diffusion

63. Equilibrium
When the concentration of the solute is the same throughout a system

64. Because diffusion depends on random particle movements, substances diffuse across membranes without energy being used
Even during equilibrium, particles still move, but there is no net change in concentration

65. Osmosis
The diffusion of water

66. Osmosis

69. Isotonic
The concentration of solutes is the same inside and outside the cell

70. Hypertonic
Solution has a higher solute concentration than the cell

71. Hypotonic
Solution has a lower solute concentration than the cell

73. Facilitated Diffusion
Movement of specific molecules across cell membranes through protein channels
Only go from high concentrations to low concentrations
Does not require energy
Glucose
molecules
High
Concentration
Cell
Membrane
Low
Concentration
Protein
channel

74. Types of Active Transport
Sometimes cells must move materials in the opposite direction
Low concentrations to high concentrations

75. Active Transport
Energy requiring process that moves materials across a cell membrane against a concentration gradient

76. Active Transport
Molecule to
be carried
Molecule
being carried
Energy

77. Molecular transport
Small molecules and ions are actively transported

78. Carrier proteins
Proteins that act like pumps

81. Endocytosis
The process of taking material into the cell by means of infolding of the membrane
Forms a vacuole
Food particle
engulfing

82. Phagocytosis
Cell eating
White blood cells do this

83. Pinocytosis
Cell drinking

84. Exocytosis
Forces contents out of the cell
Endocytosis in reverse

87. The Diversity of Cellular life
Section 3-4
The Diversity of Cellular life

88. Unicellular Organism Single celled
Do everything a living organism does

89. Multicellular Organism
Many celled
Depend on communication and cooperation among specialized cells

90. Specialization
When cells develop in different ways to perform different tasks

91. Red Blood Cells
Transport oxygen

92. Pancreatic Cells
Make proteins
Packed with ribosomes

93. Skeletal Muscle Generate force Packed with mitochondria
Overdeveloped cytoskeleton

94. Nerve Cell
Send messages

95. Guard Cells
Open and close the stomata

96. Levels of Organization
Cells
Tissues
Organs
Organ Systems

97. Tissues Group of similar cells that perform specific function
Ex.) smooth muscle

98. Organ
Group of tissues that work together to perform a specific function
Ex.) stomach

99. Organ System
Group of organs that work together to perform a specific function
Ex.) digestive system
This organization creates a division of labor that makes multicellular life possible

100. Biological Organization