1. THE CELL
Chapter 7

2. Microscopy
 Micrographs
 Photograph of the view through a microscope
 Light Microscopes
 Electron Microscopes
 Scanning EM
 To look at the surface of cells/specimen
 3-D images
 Transmission EM
 To look at internal structures of cells/specimen

14. Robert Hook (1665)
 Englishman
 cork
 “cells”
 Compound
microscope

16. Anton van Leeuwenhoek
(1660’S)
 (LAY vun
Hook)
 Holland
 Single lens
microscope
 Pond water
 “animalcules”

18. Cell Theory
 3 parts and key people

19. Cells
 Basic units of life

20. Matthias Schleiden (1838)
 German botanist
 Plant cells

21. Theodor Schwann (1839)
 German biologist
 Animal cells

22. Rudolf Virchow (1855)
 German physician
 New cells could only
come from the division
of existing cells

23. Cell Theory
 All living things are composed of one or
more cells
 Cells are the basic units of structure and
function in living things
 New Cells are produced from existing
cells

24. Lots of different shapes
and sizes of cells

28. Sizes
 The body is made of 100 trillion cell (1014)
 Extremely small…The human eye can see
.01 cm, a human cell is 5x smaller
 5 to 50 micrometers…µm
 How big is a micrometer?
 1m=100cm=1,000,000 micrometers
 1 micrometer=.000001m
 Basically you can’t see it
 Remember: KHDmDCM..micro..nano..pico

30. Chaos chaos
 Largest protozoan
 You can see without
microscope
 1000 micrometers
 How many meters is this?
 .001 m
 How many centimeters is
this?
 0.1 cm

31. 2 things in every cell…
 Surrounded by a barrier, cell membrane
 At some point in their life they contain….
 DNA

32. What is a Nucleus?
 Plural: nuclei
 Large, membrane enclosed
structure that contains the
cell’s genetic material in the
form of DNA
 What is a membrane?
 A thin layer of material that
serves as a covering or lining

34. 2 categories for cells…
 Prokaryotes (pro-care-ee-ohts)
 No nucleus
 Cell’s genetic material is not contained in the
nucleus…found in NUCLEOID:
 Region in cytoplasm where DNA is found
 Less complicated that eukaryotes
 Some have internal membranes
 Do NOT have membrane bound organelles
 Carry out every activity associated with living
things…which are…

35.  Eukaryotes (you-care-ee-othts)
 Contain nucleus in which the genetic
material is separated from the rest of the cell
 Contains dozens of structures and internal
membranes
 High Variety
 Single celled or multi-cellular
 Plants, animals, fungi, and protists

36. Eukaryotic cell
structure

37. The Cell factory
 Organelles
 Highly specialized structures within the cell
 Little organs
 2 major divisions of the eukaryotic cell
 Nucleus
 The “brain”
 DNA
 Cytoplasm
 Portion outside the nucleus but inside the cell membrane

38. 2 types of Eukaryotic cells
 Plant cells
 Animal cells
 What are the differences? (write them down!!!)

39. Nucleus
 Brain of the cell
 Office of the factory
 Contains nearly all the cell’s DNA and
with it the coded instructions for making
PROTEINS and other important
molecules

40. Nuclear envelope
 Surrounds nucleus
 Made of 2 membranes
 Dotted with thousands of nuclear pores
 How do we get messages, instructions and
blueprints out of the office?
 Allow material to move in and out of nucleus by
using “little runners” such as proteins, RNA and
other molecules

41. Inside the nucleus we
see…
 Contain a granular material called…
 CHROMATIN
 Chromatin= DNA + protein
 Usually spread out in nucleus
 During cell division, chromatin clumps
together or condenses…we call this….
 CHROMOSOMES

42. In the nucleus…
 Contain a granular material called…
 CHROMATIN
 Chromatin= DNA + protein
 Usually spread out in nucleus
 During cell division, chromatin clumps
together or condenses…we call this….
 CHROMOSOMES

43. Chromosomes
 Threadlike structures that contain genetic
information that is passed on from one
generation to the next

44. Nucleolus
 Small dense region inside the nucleus
 Function: assembly of ribosomes begin…

46. Ribosomes
 Most important function of cell is…
 Making proteins
 Proteins regulate a zillion different things
 Like…
 Proteins are assembled ON Ribosomes
 Ribosomes are small particles of protein &
RNA (what’s RNA?)
 They follow instructions from the nucleus to
make proteins…follow the orders from the
“head haunchos” in the main office
 Scattered throughout the cell
 They are like little factories
 If a cell’s main function is making proteins, how
many ribosomes are you going to have?

48. Endoplasmic reticulum
(ER)
 Internal membrane system
 The site where the lipid components of
the cell membrane are assembled, along
with proteins and other materials
exported from the cell
 2 types
 Smooth ER
 Rough ER

49. Rough ER
 Involved in protein making (synthesis)
 So what are we going to see on it?
 ribosomes
 Once a protein is made, it leaves the
ribosome and goes into the Rough ER
 The rough ER then modifies the protein
 All proteins that are exported by the cell
are made on the RER
 Membrane proteins are made on the
RER too

51. Smooth ER
 NO ribosomes on it
 Looks smooth
 Contains collections of ENZYMES that have
specialized tasks
 What do enzymes do?
 Tasks include:
 Synthesis of membrane lipids
 Detoxification of drugs
 Liver cells
 Big in detox therefore….what do u think liver cells have a
lot of?

53. Golgi Apparatus
 Discovered by Italian scientist Camillo Golgi
 Once proteins are done being “modified” in the
RER, they move onto the Golgi apparatus
 Looks like a stack of pancakes
 Function: modify, sort, and package proteins
and other materials from the ER for STORAGE
or SECRETION outside the cell
 Proteins are “shipped” to final destination
 They are the CUSTOMIZATION SHOP
 Finishing touches on proteins before they leave
factory

56. Lysosomes
 (Lie-so-soh-mz)
 The factory’s clean-up crew
 It’s an Organelle filled with
enzymes
 Function: Digestion (break
down) of lipids,
carbohydrates, and proteins
into smaller molecules that
can be used by the cell
 Also digest organelles that
have outlived their
usefulness

57. What do you think happens if
lysosomes malfunction?
 A bunch of “junk” build up in the
cell…why?
 Is this good?
 Many human diseases result from
malfunction of lysosome
 Tay-Sachs disease
 DNA does not make the enzyme
hexoaminidase A that breaks down
lipids in nerve cells
 Build up of lipids in nerve cells
causes those cells to stop working
 Noticeable 3-6 months after birth,
child lives to be about 4-5 years old

58. Vacuoles
 The factory’s storage place
 Only in certain cells
 Sac-like organelles
 Function: stores material such as water,
salts, proteins, and carbohydrates
 Plant cells have a single, large central
vacuole
 Pressure of central vacuole allows plants to
support heavy structures

60. Single-celled organisms and
some animals also have
vacuoles…
 Paramecium
 Contractile vacuole
 Contracts rhythmically to pump excess water
out…this maintains what?
 homeostasis

61. What is the one thing
all living things need
to eat, breath,
reproduce, move and
much more?
ENERGY!!!!

62. Two ways cells get
energy…
 From food molecules
 From the sun

63. Mithochondria
 Convert chemical energy stored in food
into compounds that are more convienent
for the cell to use
 Has 2 membranes
 Inner membrane
 Outer membrane
 In Animal AND Plant cells
 Nearly all come from the ovum
 You get your mitochondria from your mom!

66. Chloroplasts
 Plant and some Bacteria cells only ( NOT
in animal cells)
 Capture energy from the sunlight and
convert it into chemical energy…what is
this process called?
 PHOTOSYNTHESIS
 Like solar power for plants
 2 membranes
 Inside: large stacks of other membranes
that contain chlorphyll

69. Organelle DNA
 Chloroplasts and
mitochondria contain their
own genetic info
 In form of small, circular
DNA molecules
 mDNA

70. Lynn Margulis
 American biologist
 Chloroplasts and
mitochondria are
descendents of
prokaryotes

71. She said…
 Ancient Prokaryotes from wayyyyy back in the
day had a symbiotic relationship with the
ancient eukaryotes
 What is symbiotic? (review ecology!!!)
 The prokaryotes lived inside the eukaryotes
 There were prokaryotes that used oxygen to
make energy (ATP)
 Mitochondria
 There were prokaryotes that used
photosynthesis to get energy
 Chloroplasts

72. Endosymbiotic Theory
 Idea that
mitochondria and
chloroplasts evolved
from prokaryotes

73. Cytoskeleton
 Supporting structure and
transportation system
 Network of protein filaments that helps
the cell to maintain its shape and to help
the cell move
 2 main type of filaments
 Microtubules
 Microfilaments
(Intermediate filaments is a 3rd type)

74. Microfilaments
 Threadlike structures
 Made of protein called ACTIN
 Extensive networks
 Tough, flexible framework
 Help cells move
 Assembly and disassembly helps cells
move (like amoebas)

77. Microtubules
 Hollow structures
 Made of proteins called TUBULINS
 Maintain cell’s shape
 Important in cell division
 Make mitotic spindle (separates
chromosomes)
 Help build projections from cell surface…

78. Cilia and Flagella
 Plural: cilium and flagellum
 Cilia: hundreds of extension of the cell membrane that move like
the oars of a boat
 Flagella: one or two long extensions off the cell that move in a
whip like fashion
 Enable cells to swim rapidly through liquid

80. Centrioles
 Only animal cells
 Made of protein
TUBULIN
 What else is made of
tubulin?
 Near nucleus
 Help organize cell
division

81.  Antwon van Leeuwenhook  Golgi apparatus  Microscope
 Robert Hook  Micrometer  Micrograph
 Cell  Millimeter  Magnifier
 bacteria  Picameter  Lens
 Cell Theory  Lysosome
 Contractile vacuole
 Electron microscope  Vacuole
 Prokaryote  Mitochondria  Central Vacuole
 Eukaryote  Chloroplast  Centrioles
 Organelles  Cytoskeleton  Centrosomes
 Cytoplasm  Centriole  Nuclear pores
 Nuclear envelope  Mictrotubule  Nuclear-plasm
 Chromatin  Microfilament  Stomata
 Nucleus  Theodor Schwann  ATP synthase
 nucleolus  Matthias Schleiden  Chlorophyll
 Ribosome  Rudolph Virchow
 Cell membrane
 Smooth ER  Lynn Margulis
 Rough ER  Endosymbiotic Theory  Cell Wall
 Chromosome  Cilia  Cellulose
 Vacuole  Flagella  Phospholipids
 Osmosis  Photosynthesis  Thylakoid
 Endocytosis  Pseudopodia  Cristae
 exocytosis  Aquaporin  Matrix
 Proteins  Transmembrane protein  Inner membrane
 DNA  Facilitated diffusion  Outer memebrane
 RNA