Transcript Cells: cytology part I

CELLS: CYTOLOGY PART
I
Unit 1 Chp 3
A. STRUCTURE
1.
Cell Theory
a. Introduction
1)
Cytology – study of cells
2)
Robert Hooke – coined the word
cell
3)
Matthias Schleiden – plants made
of cells
4)
Theodor Schwann – animals made
of cells
5)
Rudolf Virchow – cells come from
b. 3 principles
2. Levels of Cellular Organization
a. Unicellular – 1 cell; algae, protozoans,
bacteria
b. Multicellular
1) Many cells
2) Colonial – similar cells living
together
3) Tissue – similar cells working
together
4) Organ – several tissues working
together
5) Organ system – group of organs
that complete a function
6) All systems rely on others for
survival
B. CELL ANATOMY
1.
Two Types
a. Eukaryotic
1)
Have membrane around nucleus
2)
Have organelles in cytoplasm
b. Prokaryotic
1)
No membrane bound nucleus
2)
No membrane bound organelles
PROKARYOTIC
EUKARYOTIC
2. Cell Boundaries
a. Plasma membranes
1) Both prokaryotic and eukaryotic
cells
2) Aka – cell membrane
3) Outermost membrane
4) Phospholipid bilayer
5) Hydrophobic/philic ends
6) Proteins let things through (pg 77)
b. Cell Walls
1) Only plants
2) Outer most layer
3) Rigid and made of cellulose
4) Primary wall – made when cell is
still
developing
5) Secondary wall
a) Produced when cell is mature
b) More cellulose than primary
wall
3. Cytoplasm
a. Holds all organelles
b. Jelly-like
c. Cytoplasmic organelles (pg 80 – 85)
1) Mitochondria
a) “Powerhouse”
b) Make energy from sugar
c) 2 membranes
i. Outer – smooth
ii. Inner
i) Lots of folds – increase surface
area
ii) Called cristae
d) Contain own DNA
e) Numerous to few in a cell
2) Ribosomes
a) Made of protein and RNA
b) Makes protein
c) Free floating or on ER
3) Endoplasmic reticulum
a) Transport system and holds shape
b) 2 kinds
i. RER – has ribosomes
ii. SER – detoxifies
Ribosomes
Endoplasmic Reticulum
4) Golgi Apparatus
a) Packaging – proteins and lipids
b) Sacs get pinched off
5) Lysosomes
a) Garbage men
b) Have digestive enzymes
c) Bacteria and nonfunctional cells
Golgi Apparatus
Lysosomes
6) Cytoskeleton
a) Frame of cell
b) Railroads
c) Has microtubules and
microfilaments
7) Flagella
a) Usually only 1
b) Long extension for locomotion
8) Cilia
a) Cover entire cell
b) Shorter than flagella
c) Can move cell or move
surroundings
9) Plastids
a) In plants and algae
b) Chloroplast – chromoplast
organelle used to change light into
energy
i. Thylakoids – flattened sacs
ii. Grana – stacks of thylakoids
which contain chlorophyll
10) Vacuoles and Vesicles (pg 85)
a) Vacuoles – Organelle that contains
water, food, waste, or other material
b) Vesicles – more mobile than
vacuoles
c) Turgor Pressure – water pressure
in a cell

Turgor Pressure – sped up


http://www.youtube.com/watch?v=fNyYuVarTIQ
Turgor Pressure – matches

http://www.youtube.com/watch?v=qrp7V0Q5qYQ
4. Nucleus
a. Control center
b. DNA replication happens here
c. Nuclear envelope
1) Double membrane around nucleus
2) Nuclear pores – openings in
envelope
3) Holds DNA
4) Nucleolus – contains RNA and
starts to make proteins
C. CELLS AND THEIR ENVIRONMENT
1.
Homeostasis
a. Keeping a steady condition
b. Constantly collects info and
interprets
c. Temperature
d. Solutions
1)
Isotonic – concentration same
inside and out of cell
2) Hypotonic
a) Higher concentration of water
outside the cell
b) Cell absorbs water
c) http://www.youtube.com/watch?v=OYoaLzobQmk
3) Hypertonic
a) Higher concentration of water
inside the cell
b) Water diffuses out
c) http://www.youtube.com/watch?v=IRQLRO3dIp8
2. Transportation across membrane
a. Passive Transport
1) No energy needed
2) Diffusion and osmosis
3) Speed
a) Size
b) Shape
c) Electrical charges
b. Active Transport
1) Need energy – against
concentration gradient
2) Aka – pump
3) Carrier proteins – allow only
certain
things to pass through
4) Na+K+ pump
c. Endocytosis and Exocytosis
1) Active transport
2) Endocytosis
a) Into the cell
b) Phagocytosis – One cell
ingesting another; solid material
c) Pinocytosis – moves fluids
3) Exocytosis – out of the cell
Endocytosis

vs. Exocytosis
http://www.youtube.com/watch?v=qpw2p1x9Cic
Sodium-Potassium

Pump
(3min)
http://www.youtube.com/watch?v=awz6lIss3hQ
Diffusion,

(2min)
solutions, and more!
http://www.youtube.com/watch?v=dPKvHrD1eS4
(12min)