BHNU

1. 11
IInnttrroodduuccttiioonn iinnttoo
CCeellll BBiioollooggyy
What is Life? What is a cell?

2. Policies
 Tests will cover information in lectures,
recitations, and reading assignments
 2 exams count towards 80% of the final grade.
Weekly problem sets count towards 20% of final
grade.
 Make-up exams will be given only for valid
reasons

3. Policies
 All exams are to be taken without books
notes.
 Please turn off your phones during
class

4. 44
IInnttrroo iinnttoo CCeellll BBiioollooggyy
-> All living
organisms are
made of cells
-> Cells are the
smallest living
unit
Human egg cell + sperm

5. IInnttrroo iinnttoo CCeellll BBiioollooggyy
 The cell is the basic unit of life.
Microorganisms such as bacteria, yeast
exist as single cells. By contrast, the
human is made up of about 30 trillion cells
(1 trillion = 1012), which are mostly
organized into collectives called tissues.
Cells are, with a few notable exceptions,
small with lengths measured in
micrometers (1000 μm = 1 mm)

7. What is a Cell?
 Cell – Basic unit of living things.
Organisms are either:
 Unicellular – made of one
cell such as bacteria
 Multicellular – made of
many cells such as plants
and animals.

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IInnttrroo iinnttoo CCeellll BBiioollooggyy
Single cell organisms – Multi cell organisms
-> Single cell organisms -> Microorganisms
Bacteria Archea Yeast - Fungi

9. 99
IInnttrroo iinnttoo CCeellll BBiioollooggyy
Single cell organisms – Multi cell organisms
-> multi cell organisms -> higher degree or
organization of cells within the organism ->
specialization of cells
Human red blood cells Human skin cells Plant cells

10. IInnttrroo iinnttoo CCeellll BBiioollooggyy
 The first person observe and record cells was Robert
Hooke (1635–1703) who described the cella (open
spaces) of plant tissues. But the colossus of this era of
discovery was Anton van Leeuwenhoek (1632–1723),
a man with no university education observer and
recorder of the microscopic living world.
 Despite van Leeuwenhoek’s Herculean efforts, it was
to be another 150 years before, in 1838,the botanist
Matthias Schleiden and the zoologist Theodor
Schwann proposed that all living organisms are
composed of cells. Their “cell theory,” which was a
milestone in the development of modern biology.

11. Scientists to Remember
 Robert Hooke (1665) – Observed
“cells” in cork

12.  Anton van Leeuwenhoek (1674)
Father of Microscopy
Saw tiny living things in pond water.

13. Cell History
 Robert Brown
 discovered the nucleus in
1833.
 Matthias Schleiden
 German Botanist
Matthias Schleiden
 1838
 ALL PLANTS "ARE
COMPOSED OF
CELLS".
 Theodor Schwann
 Also in 1838,
 discovered that animals
were made of cells

14. Cell Theory
 Confirmed discoveries that all scientists
believe to be true about cells:
1. Cells are the basic unit of life.
2. All living things are made of cells.
3. New cells are produced from
existing cells.

15. Why are cells the basic units of life?
A. The cell is the structural unit of life, All organisms
is make up of cells.

16. B.The cell is the functional unit of organisms.
All metabolic activity is based on cells.

17. C. The cell is the foundation of reproduce,
and the bridge of inheritance.

18. D. The cell is the growing and developing basis of life
Human fetal development. (a)At 5 weeks, limb buds, eyes, the
heart, the liver and rudiments of all other organs have started to
develop in the embryo, which is only about 1cm long. (b)Growth
and development of the offspring, now called a fetus, continue
during the second trimester. This fetus is 14 weeks old and about
6cm long. (c)The fetus in this photograph is 20 weeks old. Now the
fetus grows to about 30cm in length.

19. E. Cell (nucleus) is totipotent, which can create a new
organism of the same type
As a general rule, the cells of a multicellular
organism all contain the same set of genes. For
animals, the first evidence that even highly specialized
cell carry a full complement of genes was verified by
the experiment of tadpole nuclei transplanting into
unfertilized egg that had been deprived of its own
nucleus. Some can develop swimming tadpoles. This is
animal cloning.
An especially dramatic example of animal cloning
was reported in 1997. Dolly the first animal ever cloned
from a cell derived from an adult.

21. Dolly and her daughter The process of
cloning Dolly
Is there any practical value to such technology?

22. Basic properties of cells
A. Cells are highly
complex and
organized, capable
of self-regulation;
Cells acquire and
utilize energy.
B. All cells share
similar structure,
composition and
metabolic features:
Plasma membrane,
DNA/RNA, and
Ribosome.

23. C. Cells can capable of producing more of themselves,
even grow and reproduce in culture for extended
periods.
HeLa cells are
cultured tumor
cells isolated
from a cancer
patient named
Henrietta Lacks
in 1951. It is the
first human cell
to be kept in
culture for long
periods of time
and is still used
today.
Johns Hopkins
univesity,in
1951

24. D. Cells are able to respond to stimuli via surface
receptors that sense changes in the chemical
environment.
Cells within plant or animal respond to stimuli
less obviously than single-celled protist. But
they respond. They posses receptors that
interact with substances in the environment in
highly specific ways. For example, the receptor
on the cell surface can respond to hormones
and growth factors.

25. The Discovery of Cells
before nucleus
true nucleus

26. Internal Organization
Cell membrane
Prokaryotic Cell
Cell membrane
Cytoplasm
Cytoplasm
Nucleus
Organelles
Eukaryotic Cell

27. Compare and Contrast
Prokaryotes Eukaryotes
Cell membrane
Contain DNA
Ribosomes
Cytoplasm
Nucleus
Endoplasmic reticulum
Golgi apparatus
Lysosomes
Vacuoles
Mitochondria
Cytoskeleton

28. Viruses
Virus diversity
1.Viruses are pathogens
first described in the late
1800s.
2. Viral structure:
a)The genetic material:
Single- or double- straded
DNA orRNA.
b)obligatory intracellular
parasites.
3.Viral infection types:
a)Lytic infection; b)integrated infection

29. 4. Viral origins:
a)Viruses had to arise after their hosts evolved;
b)Viruses probably arose as fragments of host chromosomes.
5.Viroids
6.prion

30. 3322
Size of the cells
The smallest objects that the
unaided eye can see are about 0.1
mm long. That means under the
right conditions, you might be able
to see a human Smaller cells are
easily visible under a light
microscope. It's even possible to
make out structures within the cell,
such as the nucleus, mitochondria
and chloroplasts. The most
powerful light microscopes can
resolve bacteria but not viruses.
To see anything smaller than 500
nm, you will need an electron
microscope.

31. Cell Size
 Female Egg - largest cell in the human body;
seen without the aid of a microscope
 Most cells are visible only with a
microscope.

32. Microscopes
 Light Microscope – magnifies tiny organisms
up to 1,000 times.
-Uses light and lenses.
-We use these.
 Electron Microscope – magnifies
up to a million times.
-Uses electrons.

34. Cells are small for 2 Reasons
Reason 1:
 Limited in size by the ratio between their
outer surface area and their volume.
A small cell has more surface area than a
large cell for a given volume of crtoplasm.

35. Cells are Small
Reason 2:
 The cell nucleus can only control a
certain amount of living,active
cytoplasm.

36. Cell Shape
 Diversity of form reflects a
diversity of function.
 The shape of a cell
depends on its function.

37. 339
Evolutionary time line

38. 4400
IInnttrroo iinnttoo CCeellll BBiioollooggyy
Different Types of Cells
There are two main groups
of cells, prokaryotic and
eukaryotic cells. They differ
not only in their
appearance but also in
their structure,
reproduction, and
metabolism. However, all
of the cells belong to one of
the five life kingdoms. The
greatest difference lies
between cells of different
kingdoms. The following
diagram shows the five
kingdoms: monera,
protista, plantae, fungi, and
animalia.

39.  In biology, evolution is any change across
successive generations in the heritable
characteristics of biological populations.
Evolutionary processes give rise to diversity at
every level of biological organization, from
kingdoms to species, and individual organisms
and molecules such as DNA and proteins. The
similarities between all present day organisms
indicate the presence of a common ancestor
from which all known species, living and extinct,
have diverged through the process of evolution.

40. 4422
IInnttrroo iinnttoo CCeellll BBiioollooggyy
Two cell types - The Three Domain System
Prokaryotes
The three major
divisions of the
living world.
The tree shown here
is based on
comparisons of the
nucleotide sequence
of a
ribosomal RNA
subunit in the
different species.

41. Explore
 Plant vs. Animal Lab
 You will observe different types of plant and animal cells
under the microscope and record your observations.
 Gel Cells for Diffusion
 You will build a model of a cell to understand why cells
when they reach a certain size stop growing.
 Edible Model Cells
 Using your textbook and other resources, you will make a
model of a prokaryotic and eukaryotic cell using gelatin and
other edible materials. The gelatin will represent the cell
membrane/cytoplasm and other edible components will be
representative of the cellular organelles.

42. Cell Substructure

43. Eukaryotic Cell Substructure
 The cell is the basic unit of life. Broadly
speaking, there are two types of cells:
prokaryotic and eukaryotic. Prokaryotes
(eubacteria and archaea) do not have a
nucleus; that is, their DNA is not enclosed
in a special, subcellular compartment with
a double membrane. Eukaryotic cells do
have a nucleus; they are also much larger
than prokaryotic cells and have numerous
organelles and certain substructural
elements not found in prokaryotes.

44. Eukaryotic Cell Substructure
Plant and Animal Cells

45. ANIMAL CELL

46. Mitochondria
Structure - composed of
modified double unit
membrane (protein,
lipid)
 inner membrane
infolded to form cristae
 Function - site of
cellular respiration ie.
the release of chemical
energy from food
Glucose + Oxygen ------> Carbon
Dioxide + Water + Energy (ATP)
DNA
Inter-membrane space

47. Cytoskeletal structures
Cells contain elaborate
arrays of protein fibers
that serve such
functions as:
 Establishing cell shape
 Providing mechanical
strength
 Locomotion (cilia,
flagella)
 Chromosome
separation in mitosis
and meiosis
 Intracellular transport of
organelles

48. Major components of cytoskeletal
system
 Intermediate
Filaments
 Microtubules
 Actin filaments
www.cytochemistry.net/Cell-biology/filam.htm

49. Rough and Smooth
Endoplasmic
Reticulum
•Endo means within
•Plamic refers to the
cytoplasm
•Reticulum means a
network.
Thus the endoplasmic
reticulum is a series of
interconnected,
intracytoplasmic,
membrane bounded
sacs.

50. Rough endoplasmic reticulum (RER)
• appear rough due to presence of ribosomes
•involved in protein synthesis.
Smooth endoplasmic reticulum (SER)
•has no ribosomes
•The SER is involved in
•cholesterol metabolism,
•membrane synthesis, (Lipids)
•Detoxification,
•Ca++ storage along with other cellular processes.

51. Vesicles
Membrane bound intracellular sacs
 transport vesicles
 endocytotic vesicles
 exocytotic vesicles
 lysosomal vesicle
 secretory vesicle
 adipose vesicles

52. Golgi Apparatus/Body
 Proteins are
transported from the
RER to the golgi
apparatus and from
the golgi apparatus to
the plasma
membrane in
transport vesicles.

53. Lysosmes
A primary lysosome
contains many enzymes
 synthesized in the RER
and sorted in the golgi.

54. Peroxisomes/Micorbodies
 Organelles that contain enzymes to
degrade
fatty acids and amino acids.
A biproduct of this degradation is H2O2
hydrogen peroxide – highly toxic to proteins
 Also contain the enzyme catalase which
destroys H2O2
 The enzymes are synthesized on the RER
and are sorted/refined into the
peroxisomes in the golgi apparatus

56. Nucleus
 The nuclear compartment contains the
chromosomes, the primary genetic material, as
well as all the enzymes for transcribing
chromosomal DNA into RNA, processing that
RNA, and exporting it out to the cytoplasm; in
addition, it contains all the transcription factors
and chromatin remodeling factors required for
regulating RNA transcription. It is surrounded by
a double membrane, which is perforated at
several thousand locations all over its surface by
elaborate, protein-based pore structures
(nuclear pore)

57. PLANT CELL

58. Cell Wall
 Cell walls are made of
specialized sugars
called cellulose.
 Cellulose is called a
structural
carbohydrate
(complex sugar)
because it is used in
protection and
support.

59. Cell Wall
 Function
 help a plant keep its
shape
 protect the cells
 allow plants to grow
to great heights
 For smaller plants,
cell walls are slightly
elastic

60. Plastids
 Large cytoplasmic
organelles found in the
cells of most plants
 There are three plastid
categories-
 Leucoplasts (white or
colorless plastids that store
starch granules) ,
 Chromoplasts (colored
plastids that store pigment
molecules like cartenoids
which store yellow and
orange pigment)
 Chloroplasts which are
essential in the
photosynthetic process

61. Leukoplasts
 non-pigmentous, 2x5
μm, variable shaped
plastids for storage
 3 types:
AMYLOPLASTS
(starch),
ALEUROPLAST
(protein),
ELAIOPLASTS (oils)

62. Chromoplasts
 Chromoplast are derived
from chloroplast.
 Synthesize carotenoid
pigments such as
carotene or lycopene.
 Found in flowers, fruit,
and leaves in stress or
senescence.
 In flowers, carotenoid
pigment enables the
forming of different color,
which can attract insects
and other pollinators.

63. Chloroplasts
 Site of photosynthesis.
 500,000 chloroplasts per
square millimeter of leave
surface
 Contain chlorophyll, the
green pigment that absorbs
energy from sunlight
 Sunlight captured by
chlorophyll enables carbon
dioxide from the air to unite
with water and minerals
from the soil and create
food.
 Chlorophyll gives plants
their characteristic green
color.
DNA

65. How Plant and Animal Cells
Differ
PLANT CELLS
 Cell walls present
 Plastids occur in
cytoplasm
 Lysosomes not usually
evident
 Centrioles present only
in cells of lower plant
forms
 Large vacuoles filled
with cell sap
ANIMAL CELLS
 No cell walls
 No plastids are found
 Lysosomes occur in
cytoplasm
 Centrioles always
present
 Vacuoles, if present,
are small and
contractile or temporary
vesicles

66. 6688
IInnttrroo iinnttoo CCeellll BBiioollooggyy
Cell Types

67. 6699
IInnttrroo iinnttoo CCeellll BBiioollooggyy
Prokaryotes – Domain Bacteria
-->> SSiinnggllee cceellll oorrggaanniissmmss
-->> NNoo nnuucclleeuuss,, nnoo ccoommppaarrttmmeennttss
-->> PPeeppttiiddooggllyyccaann cceellll wwaallllss
-->> BBiinnaarryy ffiissssiioonn
-->> FFoorr eenneerrggyy,, uussee oorrggaanniicc
cchheemmiiccaallss,, iinnoorrggaanniicc cchheemmiiccaallss,,
oorr pphhoottoossyynntthheessiiss

68. 7700
IInnttrroo iinnttoo CCeellll BBiioollooggyy
Prokaryotes – Domain Archea
-->> LLaacckk ppeeppttiiddooggllyyccaann
-->> LLiivvee iinn eexxttrreemmee eennvviirroonnmmeennttss
IInncclluuddee::
MMeetthhaannooggeennss
EExxttrreemmee hhaalloopphhiilleess
EExxttrreemmee tthheerrmmoopphhiilleess
-->> RRoollee iinn ddiisseeaassee nnoott wweellll
uunnddeerrssttoooodd——tthhiiss ggrroouupp hhaass oonnllyy
rreecceennttllyy bbeeeenn ddiissccoovveerreedd Thermophiles growing in
Yellowstone hot springs.

69. 7711
IInnttrroo iinnttoo CCeellll BBiioollooggyy
LLiiffee oonn MMaarrss??
Magnified view of objects in Martian meteorite found in
Antarctica. (Archaeobacteria like?)

70. 7722
IInnttrroo iinnttoo CCeellll BBiioollooggyy
Domain Eukaryotes
-->> PPllaannttaaee
mmuullttiicceelllluullaarr ppllaannttss,, cceelllluulloossee cceellll wwaallll,, pphhoottoossyynntthheessiiss
-->> FFuunnggii
CChhiittiinn cceellll wwaallllss
UUssee oorrggaanniicc cchheemmiiccaallss ffoorr eenneerrggyy
MMoollddss aanndd mmuusshhrroooommss aarree mmuullttiicceelllluullaarr ccoonnssiissttiinngg ooff mmaasssseess ooff
mmyycceelliiaa,, wwhhiicchh aarree ccoommppoosseedd ooff ffiillaammeennttss ccaalllleedd hhyypphhaaee
-->> PPrroottiissttss
PPrroottoozzooaa,, mmoottiillee vviiaa ppsseeuuddooppooddss,, cciilliiaa,, oorr ffllaaggeellllaa
AAllggaaee,, pphhoottoossyynntthheettiicc
-->> AAnniimmaalliiaa
MMuullttiicceelllluullaarr aanniimmaallss,, PPaarraassiittiicc ffllaattwwoorrmmss aanndd rroouunndd wwoorrmmss aarree
ccaalllleedd hheellmmiinntthheess. MMiiccrroossccooppiicc ssttaaggeess iinn lliiffee ccyycclleess

71. 7733
FFuunnggii
Slime mold
IInnttrroo iinnttoo CCeellll BBiioollooggyy
Yeast

72. 7744
FFuunnggii

73. 7755
PPrroottoozzooaa
Euglena
Amoeba
IInnttrroo iinnttoo CCeellll BBiioollooggyy
Paramecium

74. 7766
PPrroottoozzooaa -- AAllggaaee
IInnttrroo iinnttoo CCeellll BBiioollooggyy

75. 7777
IInnttrroo iinnttoo CCeellll BBiioollooggyy
Viruses -> are NO living organisms -> parasites
-->> CCoonnssiisstt ooff DDNNAA oorr RRNNAA ccoorree
-->> CCoorree iiss ssuurrrroouunnddeedd bbyy aa pprrootteeiinn ccooaatt
-->> CCooaatt mmaayy bbee eenncclloosseedd iinn aa lliippiidd eennvveellooppee
-->> VViirruusseess aarree rreepplliiccaatteedd oonnllyy wwhheenn tthheeyy aarree iinn aa
lliivviinngg hhoosstt cceellll
-->> NNoott cceelllluullaarr

76. 7788
IInnttrroo iinnttoo CCeellll BBiioollooggyy
Cell growth -> cell division Cell death -> apoptosis

77. 7799
IInnttrroo iinnttoo CCeellll BBiioollooggyy
Cell Movement -> Motility -> Flagellum
Pseudomonas (3,300X) Salmonella (1200X)