This document discusses microscopy and cell structure. It begins by describing different types of microscopes used to study cells, including light microscopes and electron microscopes. It then summarizes the key contributors to the Cell Theory, including Hooke, van Leeuwenhoek, Schleiden, Schwann, and Virchow. The rest of the document details the structures and organelles found within eukaryotic cells, including the nucleus, mitochondria, chloroplasts, endoplasmic reticulum, Golgi apparatus, lysosomes, vacuoles, cytoskeleton, and cell membrane. It emphasizes that cells are the basic functional units of living things.

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. Microscopes

29. 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

31. 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

32. 2 things in every cell…
 Surrounded by a barrier, cell membrane
 At some point in their life they contain….
 DNA

33. 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

35. 2 categories for cells…
 Prokaryotes (pro-care-ee-  Eukaryotes (you-care-ee-othts)
ohts)  Contain nucleus in which the
 No nucleus genetic material is separated from
 Cell’s genetic material is the rest of the cell
not contained in the
nucleus…found in  Contains dozens of structures and
NUCLEOID: internal membranes
 Region in cytoplasm  High Variety
where DNA is found  Single celled or multi-cellular
 Less complicated that  Plants, animals, fungi, and protists
eukaryotes
 Some have internal
membranes
 Do NOT have membrane
bound organelles
 Carry out every activity
associated with living
things…which are…

41. Eukaryotic cell
structure

42. 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

43. 2 types of Eukaryotic cells
 Plant cells
 Animal cells
 What are the differences? (write them down!!!)

44. 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

45. 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

46. 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

47. 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

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

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

51. 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?

53. 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

54. 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

56. 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?

58. 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

61. 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

62. 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

63. 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

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

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

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

68. 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!

71. 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 chlorophyll

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

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

76. 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

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

78. 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)

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

82. 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…

83. 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

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

86.  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