1. Regents Biology
Cells: Two main types

2. Regents Biology
before
nucleus
true
nucleus

3. Regents Biology
Prokaryotes
1. NO nucleus
1. unicellular
1. NO membrane-bound organelles
(just ribosomes)
2. Forerunner to eukaryotic cells
(smaller, simpler)
3. DNA – single strand and circular
-Bacteria, archaea

4. Regents Biology
Eukaryotes
1.Has a nucleus with a nuclear
envelope
2.Bigger and more complex than
prokaryotes
3.Have membrane bound organelles
4.DNA – double-stranded and forms
chromosomes (highly organized)
5. Uni- OR multicellular organisms
animals, plants, fungi…

5. Regents Biology
Similarities
1. Contain all four biomolecules
(lipids, carbs, proteins, and nucleic acids)
1. Have ribosomes (eukaryotes 80S,
prokaryotes 70S)
2. Have DNA
3. Similar Metabolism
4. Can be unicellular
5. Have cell/plasma membranes or cell wall

6. Regents Biology
Evolution of Eukaryotic Cells

7. Regents Biology
Organelles
 Organelles do the work of cells
 each structure has a job
 keeps the cell alive; keeps you alive
Model Animal Cell

8. Regents Biology
cell membrane
cell boundary
controls movement
of materials in & out
recognizes signals
Cytoplasm
lattice-like material holding
organelles in place

9. Regents Biology
Cell membrane
 Function
 Barrier
 Control
 O2,CO2, food, H2O, nutrients, waste
 Communication
 between cells
 Structure
 phospholipid bilayer
 receptor molecules
 proteins
lipid “tail”
phosphate
“head”

10. Regents Biology
Vesicles  Function
 Transport
 Endocytosis
 Exocytosis
 Structure
 membrane sac
large food
particle
vesicle
Proteins etc
Endocytosis!
Exocytosis!

11. Regents Biology
Vacuoles: Storage
plant cells
contractile
vacuole
animal cells
central vacuole
food vacuoles

12. Regents Biology
cell membrane
cell boundary
controls movement
of materials in & out
recognizes signals
cytoplasm
lattice material holding
organelles in place
vacuole & vesicles
storage
transport

13. Regents Biology
Lysosomes
 Function
 little “stomach” of the cell
 digests macromolecules
 “clean up crew” of the cell
 cleans up broken down
organelles
 Structure
 vesicles of digestive
enzymes
only in
animal cells
synthesized by rER,
transferred to Golgi
Where
old organelles
go to die!
 lyso– = break apart
 –some = body

14. Regents Biology
Lysosomes
white blood cells attack
& destroy invaders =
digest them in
lysosomes
1974 Nobel prize: Christian de Duve
Lysosomes discovery in 1960s
1960 | 1974

15. Regents Biology
When things go bad…
 Diseases of lysosomes are often fatal
 digestive enzyme not working in lysosome
 picks up biomolecules, but can’t digest one
 lysosomes fill up with undigested material
 grow larger & larger until disrupts cell & organ
function
 lysosomal storage diseases
 more than 40 known diseases
 example:
Tay-Sachs disease
build up undigested fat
in brain cells

16. Regents Biology
But sometimes cells need to die…
 Lysosomes can be used to kill cells when
they are supposed to be destroyed
 some cells have to die for proper
development in an organism
 apoptosis
 “auto-destruct” process
 lysosomes break open & kill cell
 ex: tadpole tail gets re-absorbed
when it turns into a frog
 ex: loss of webbing between your
fingers during fetal development

17. Regents Biology
Fetal development
15 weeks
6 weeks
syndactyly

18. Regents Biology
Apoptosis
 programmed destruction of cells in multi-
cellular organisms
 programmed development
 control of cell growth
 example:
if cell grows uncontrollably this self-destruct
mechanism is triggered to remove damaged cell
 cancer must over-ride this to enable tumor
growth

19. Regents Biology

20. Regents Biology
lysosome
food digestion
garbage disposal &
recycling
cell membrane
cell boundary
controls movement
of materials in & out
recognizes signals
cytoplasm
lattice-like material
holding
organelles in place
vacuole & vesicles
transport
storage

21. Regents Biology
Making Energy
 Cells must convert incoming energy to
forms that they can use for work
 mitochondria:
from glucose to ATP
 chloroplasts:
from sunlight to ATP & carbohydrates
 ATP = active energy
 carbohydrates = stored energy
+
ATP
ATP

22. Regents Biology
Mitochondria & Chloroplasts
 Important to see the similarities
 transform energy
 generate ATP
 double membranes = 2 membranes
 semi-autonomous organelles
 move, change shape, divide
 internal ribosomes, DNA & enzymes

23. Regents Biology
Mitochondria
 Function
 make ATP energy from cellular respiration
 sugar + O2  ATP
 fuels the work of life
 Structure
 double membrane
in both animal &
plant cells
ATP

24. Regents Biology
lysosome
food digestion
garbage disposal &
recycling
cell membrane
cell boundary
controls movement
of materials in & out
recognizes signals
cytoplasm
lattice-like material
holding
organelles in place
vacuole & vesicles
transport inside cells
storage
mitochondria
make ATP energy
from sugar + O2

25. Regents Biology
Plants make energy two ways!
 Mitochondria
 make energy + O2 from sugar
 cellular respiration
 sugar + O2  ATP
 Chloroplasts
 make energy + sugar from sunlight
 photosynthesis
 sunlight + CO2  ATP & sugar
 ATP = active energy
 sugar = stored energy
 build leaves & roots & fruit
out of the sugars
ATP
sugar
ATP

26. Regents Biology
Mitochondria

27. Regents Biology
Dividing Mitochondria
Who else divides
like that?
What does this tell us about
the evolution of eukaryotes?

28. Regents Biology
Mitochondria
 Almost all eukaryotic cells have mitochondria
 there may be 1 very large mitochondrion or
100s to 1000s of individual mitochondria
 number of mitochondria is correlated with
aerobic metabolic activity
 more activity = more energy
needed = more mitochondria
What cells would
have a lot of
mitochondria?
active cells:
• muscle cells
• nerve cells

29. Regents Biology
Mitochondria are in both cells!!
animal cells plant cells
mitochondria
chloroplast

30. Regents Biology
Chloroplasts
 Function
 photosynthesis
 generate ATP & synthesize sugars
 transform solar energy into chemical energy
 produce sugars from CO2 & H2O
 Semi-autonomous
 moving, changing shape & dividing
 can reproduce by pinching in two
Who else divides
like that?
bacteria!

31. Regents Biology

32. Regents Biology
Endosymbiosis theory
 Mitochondria & chloroplasts were once
free living bacteria
 engulfed by ancestral eukaryote
 Endosymbiont
 cell that lives within another cell (host)
 as a partnership
 evolutionary advantage
for both
 one supplies energy
 the other supplies raw materials
& protection
Lynn Margulis
U of M, Amherst
1981 | ??

33. Regents Biology
Endosymbiosis theory
Evolution of eukaryotes

34. Regents Biology
Endosymbiosis
Evidence
• Mitochondrial has its own DNA
• Mitochondrial DNA more
similar to bacterial DNA than nuclear DNA of
cell
• Mitochondria divide by binary fission, not
mitosis

35. Regents Biology
central vacuole
storage: food,
water or waste
mitochondria
make ATP in
cellular respiration
chloroplast
make ATP & sugars in
photosynthesis
cell wall
support
cell membrane
cell boundary
controls movement
of materials in & out
recognizes signals
lysosome
digestion & clean up
cytoplasm

36. Regents Biology
Cells need workers (proteins)!
 Making proteins
 to run daily life & growth, the cell must…
 read genes (DNA)
 build proteins
 structural proteins (muscle fibers, hair, skin, claws)
 enzymes (speed up chemical reactions)
 signals (hormones) & receptors
 organelles that do this work…
 nucleus
 ribosomes
 endoplasmic reticulum (ER)
 Golgi apparatus

37. Regents Biology
Proteins do all the work!
cellsDNA proteins
one of the major job of cells is to make proteins,
because…
proteins do all the work!
signals
structure
enzymes
receptors

38. Regents Biology
Nucleus
 Function
 control center of cell
 protects DNA
 instructions for building proteins
 Structure
 nuclear membrane
 nucleolus
 ribosome factory
 chromosomes
 DNA

39. Regents Biology
Ribosomes on ER
Ribosomes
 Function
 protein factories
 Eukaryotes have 80S, prokaryotes 70S
 read instructions to build proteins from DNA
 Structure
 2 subunits
 some free in cytoplasm
 some attached to ER
large
subunit
small
subunit

40. Regents Biology
Endoplasmic Reticulum
 Function
 part of protein factory
 helps complete the
proteins
 makes membranes
 Structure
 rough ER
 ribosomes attached
 works on proteins
 smooth ER
 makes membranes

41. Regents Biology
lysosome
food digestion
garbage disposal &
recycling
cell membrane
cell boundary
controls movement
of materials in & out
recognizes signals
cytoplasm
jelly-like material holding
organelles in place
vacuole & vesicles
transport inside cells
storage
mitochondria
make ATP energy
from sugar + O2
nucleus
protects DNA
controls cell
ribosomes
builds proteins
ER
helps finish proteins
makes membranes

42. Regents Biology transport vesicles
vesicles
carrying proteins
Golgi Apparatus
 Function
 finishes, sorts, labels & ships proteins
 like UPS headquarters
 shipping & receiving department
 ships proteins in vesicles
 “UPS trucks”
 Structure
 membrane sacs

43. Regents Biology
cell membrane
cell boundary
controls movement
of materials in & out
recognizes signals
cytoplasm
lattice material holding
organelles in place
vacuole & vesicles
transport inside cells
storage
mitochondria
make ATP energy
from sugar + O2
nucleus
protects DNA
controls cell
ribosomes
builds proteins
ER
helps finish proteins
makes membranes
Golgi apparatus
finishes, packages
& ships proteins
lysosome
food digestion
garbage disposal &
recycling

44. Regents Biology
central vacuole
storage: food,
water or waste
mitochondria
make ATP in
cellular respiration
chloroplast
make ATP & sugars in
photosynthesis
cell wall
support
cell membrane
cell boundary
controls movement
of materials in & out
recognizes signals
Golgi apparatus
finish & ship
proteins
nucleus
control cell
protects DNA
endoplasmic reticulum
processes proteins
makes membranes
lysosome
digestion & clean up
cytoplasm
ribosomes
make proteins