What do I and my classmates already know
re: eukaryotic cells? 11/3/15
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Plant cells have edges; more box shaped
Animals cells are rounded in general
Unicellular & multicellular organisms
Every living thing has 1 or +1 cells=a
characteristic of life
Cells can be auto- or heterotrophic
White & red blood cells in animals
Are microscopic; r super tiny!
Have a nucleus
Building blocks of life
Some do not have a nucleus
Cells make tissues
White blood cells heal wounds
Plant cells have chloroplasts which are
green
Human body has 100+ trillion cells in it
10,000 can fit on the head of a pin
500 quadrillion chem. rxns per sec. w/in
cells
Come in 1000’s shapes & sizes
Protect us from harm…or cause harm
What is the Cell Theory & Hx of microbiology?
11/4/15
CELL THEORY:
 Cell Theory= explanation re: the
relationship btwn cells & living things
 Cell Theory states: all living things are
composed of cells, cells are the basic unit
of structure & fxn in living things (cells are
the smallest unit of life), cells come from
other cells
 Developed by Schleiden, Schwann &
Virchow in mid-1800’s
-------------------------------------------------------------------HX OF MICROBIOLOGY:
 microbiology= study of small
organisms…micro=teeny; bio=life; ology=
study of “teeny life study”
 microscopes improved magnification over
the yrs & got “more techy”
 1st microscope made in 1590; made
discovery of cells possible; Zacharias
Jansen
 Robert Hooke (1660 ish) observed cork
under microscope…came up w/ the term
“cell” to name what he saw
 Robert Brown discovered the nucleus in
mid 1800’s
 Leeuwenhoek 1st to see unicellular
organisms (1660’s)
What are the ingredients of cells? 11/13/15
 Cells are…
-DNA&RNA (nucleic acids)=1.5 % wgt
-lipids (fats)=1% wgt
-proteins=5% wgt
-carbohydrates (sugar)=2.5% wgt
-H2O=90% of wgt
What is the basic structure of eukaryotic
cells? 11/16/15
 organelle= organ-type things inside cells
that carry out the cell’s life functions;
parts & pieces
Taped in double chart of organelles-see pic on
website!
 Some cells have more of one organelle than
others; some cells do not have certain
organelles b/c they don’t need them
---EX: plant root cells do not have
chloroplasts b/c they are underground &
don’t need them
 Animal cells are many shapes & sizes, but
plant cells are boxy shaped only
(tape in)
How do plant and animal cell structures
compare? 12/4/15
PLANT CELL
BOTH
ANIMAL CELL
ONLY
ONLY
cell membrane
cell wall
lysosomes
chloroplasts nucleus= eukaryotic cytoskeleton
ribosomes
many small vacuoles
(1:organelle
Golgi bodies any shape but
difference)
Cytoplasm
a box
box-like shape
ER
(2: shape
vacuole
difference)
mitochondria
1 BIG vacuole
(3: vacuole
difference)
How does the cell membrane work? 1/4/16
 Cell membrane is selectively permeable=
has little holes that allow small molecules
to pass through, but not thick/big ones.
 Diffusion= mvmt of molecules through a
selectively permeable membrane from high
to low concentration
 Molecules bump into e@ other & move until
they are evenly spread out= equilibrium
(student drawn diagram of diffusion)
High
concentration
on top
Low
concentration
Equilibrium is
reached!
on bottom
 Osmosis=diffusion of water… Many cellular
processes depend on osmosis
-Isotonic= even H2O & other stuff inside &
outside of the cell…ideal state of
equilibrium/homeostasis!
-Hypotonic= water rushes into the cell b/c of
low concentration of H2O inside cell…animal
cells will explode  but plant cells expand to
rigidity …(high water concentration so
swollen & does NOT need H2O)
-Hypertonic= water rushes out of the cell b/c
low concentration of H2O outside cell…plants
wilt & animals get really thirsty…(low water
concentration so needs H2O)
What is the difference between passive and
active transport across the cell membrane?
1/12/16
ACTIVE TRANSPORT
PASSIVE TRANSPORT
-cell uses its own energy to get
stuff across the membrane
-does NOT take the cells
energy to move stuff across
the membrane
-transport proteins act like a
door in the membrane to
allow lrg molecules through
-engulfing is another form of
active transport…cell
membrane surrounds a
molecule and pulls it into the
cell
-like riding a bike uphill
Moves stuff
across the
cell
membrane
Mvmt just happens from high
to low concentration
-osmosis and diffusion
-like riding a bike downhill
What is the structure and fxn of DNA found in
the nucleus? 1/13/16
(tape in highlighted for information)
 DNA proteins code for what you look like=
phenotype
 DNA proteins tells the pepper tree to be a
pepper tree, a frog to be a frog, me to be
me
 Shape/structure of DNA molecule
discovered by Watson & Crick in 1953
 DNA is white in every living thing!
(student drawn diagram of DNA double
helix)
What is photosynthesis? 1/22/16
 Photosynthesis= the way a plant cell
captures energy from the sun to create
food…converting radiant energy into
chemical energy that an organism can
use…use radiant energy to convert H2O &
CO2 into O2 & sugar
 Ingredients for photosynthesis:
What is required & how does plant get it?
1) sunlight energy (photons) captured in the
chloroplasts by chlorophyll=green chemical
in chloroplasts…solar cell
2) CO2 (carbon dioxide) from the air through
the leaf stomata=tiny pores on the underside
that open and close…gets into chloroplast by
diffusion
3) H2O (water) absorbed by the roots from the
soil during osmosis
 The process of photosynthesis (stage two)
is a WICKED chemical reaction using the
sun energy to rip apart CO2 & H2O
molecules to get C, O, H atoms…occurs in
chloroplasts
 Products of photosynthesis:
1) O2 (oxygen) passes through the stomata
into the atmosphere
2) Sugar (glucose=C6H12O6) which is the
energy for living/life processes or stored
for later use as starch (plant fat).
 Photosynthesis equation:
6CO2+6H2O+sunlight photons
yields
C6H12O6+6O2
“six carbon dioxide molecules plus six water
molecules plus sunlight photons yields one
glucose molecule plus six oxygen molecules.”
Why do the leaves of some trees change color
in autumn? 2/3/16
 Anthocyanin=red pigment in leaves created
@ the end of summer
 Carotenoids=orange/yellow pigment in
leaves…more common than
anthocyanins…always present in leaves-the
true color of the leaf
 Deciduous trees= loose leaves in autumn…
AKA broad leaf trees
 When days get shorter, trees stop making
chlorophyll…loose green pigment
 Fewer hours of sunlight in autumn means
less photosynthesis can happen…change
color due to weather
 Conifers/pines do NOT loose
leaves/needles
What is cellular respiration? 2/4/16
 Cellular respiration= releasing energy from
glucose…happens in the mitochondria
 ALL organisms do CR!!!
 Ingredients of CR:
1) Glucose/sugar (C6H12O6)…animals eat
food…plants do photosynthesis
2) Oxygen (O2) from the
atmosphere…animals inhale & plants
through stomata
 Process of CR: a wicked chemical rxn in the
mitochondria to release energy from
glucose
 Products of CR:
1) CO2 released by exhaling or through
stomata in plants
2) H2O released by exhaling or through
stomata in plants
3) Energy in the form of ATP (38 molecules
from 1 molecule of glucose)
 Cellular Respiration equation:
C6H12O6+6O2
6H2O+6CO2+energy (ATP)
One glucose molecule plus six oxygen
molecules yields six water molecule plus 6
carbon dioxide molecule plus energy as
ATP (38).
How are photosynthesis and cellular
respiration related? 2/16/16
 Photosynthesis and CR are opposite
reactions
 The products of one are the ingredients
of the other
 Photosynthesis and CR keep CO2 and O2
in balance in the atmo.=oxygen cycle
What is fermentation? 2/23/16
 Fermentation= release energy w/o
O2…releases a lower amt of energy than
CR-NOT as efficient as CR
 2 types of fermentation:
1) Alcoholic Fermentation= done by
yeast! Adds alcohol & bubbles to beer
and wine; causes bread to rise…
C6H12O6+zymase
2 C2H5OH+2CO2
(alcohol)
2) lactic acid fermentation= done by
muscle cells when they run out of
oxygen…makes you sore and weak
C6H12O6
2 CH3CHOHCOOH
(lactic acid)
also done by bacteria to make yogurt &
sauerkraut
What is the cell cycle…AKA mitosis?
fxn #3 2/24/16
 cell cycle= sequence of cells dividing
into “daughter cells” and then repeat!
 Three stages to this sequence:
1) Interphase: cell grows, replicates DNA
& prepares to divide in two
--DNA replicates by untwisting then
“unzipping” & “zipping in” a new ½
strand (diagram)
“Intermission”=the break in the
action
--90% of total time for the cell cycle
2) Mitosis: “make two identical nuclei”
out of one nucleus in 4 stages/phases
*Prophase=DNA starts to “pack
together”
*Metaphase= nuclear membrane
dissolves & DNA lines up in the
“middle of the cell”
*Anaphase= DNA pairs are pulled
“apart” by spindle fibers (thread
thingies)
*Telophase=two, identical nuclei are
formed in ONE stretched out cell
(small diagrams of e@ phase)
--9% of the total time of the cell cycle
3) Cytokinesis: cell divides into 2
identical “daughter cells”
--“completely split” … “cytoplasm
divides”…
--cell membrane pinches in to make
the split in animal cells
--cell plate forms in plant cells to split
the cell
--1% of the total time of the cell cycle
 How long it takes depends on the type
of cell in the organism
What is differentiation? 3/7/16 Fxn #4
 Cellular differentiation= the process of
creating differences in cell structure &
fxns in multicellular organisms…a
differentiated cell “has chosen a career
and will stay there until death!”
 Differentiate when parts of DNA turn
OFF
 How much differentiation depends on
the cell’s fxn
 Stem cells= undifferentiated cell that
can make any cell the organism needs…
“doesn’t know what it wants to be when
it grows up b/c it can be anything”
 Regeneration= regrow a lost body part
b/c of stem cells @ the point of injury
EX: lizard tails & starfish arms & heal
nonfatal wounds (broken bones, cuts
etc.)