Transcript Two main cells: Prokaryotes and Eukaryotes

Cells of different kinds of organisms:
TWO MAIN CELLS: PROKARYOTES AND
EUKARYOTES
TWO MAIN CELLS: PROKARYOTES AND EUKARYOTES
PROKARYOTES
EUKARYOTES
Kingdom monera
Plant and animal kingdom etc.
Unicellular/or very simple multicellular
Multicellular
Bacteria/cyanobacteria
Plant cells, animal cells, fungi, protists
Small
Larger up to 100um in plants
Lack membrane bound organelles
Many organelles-membrane bound
Large surface area to volume ratio-efficient at diffusion
The smaller surface area to volume ration although still large
enough to be quite efficient – they divide when they are
becoming less efficient
Single circular DNA Chromosome plus some have plasmids
DNA in the culclues- thread like chromosomes
Cell wall is made of protein and complex carbohydrates
Cell wall-plants-largely cellulose Fungi-cell wall –chitin-a
polysaccharide
YEAR 11 CELL DIFFERENTIATION NOTES





Single cell/Unicellular organisms:
All organisms consist originally of a single cell
This is capable of performing all of the functions
necessary for life
These functions are under the control of the nucleus
Examples of single celled organisms include:




Amoeba;
euglena and Paramecium
AMOEBA


Outer cell membrane

Outer cell membrane



Contractile
Water Vacuole

Contraclile
Water Vacuole


Food Vacuole
Food Vacuole


Granular Cytoplasm


Granular Cytoplasm



Pseudopodium (foot)
Pseudopodium (foot)
EUGLENA
PARAMECIUM
UNICELLULAR ORGANISMS
These will continue to grow, provided their
surface area to volume ratio allows for efficient
function
 This means that the gas exchanged and food
substances and waste material is able to be
removed or provide sufficient energy for the cell
to survive for life to continue

CONSIDER THE FOLLOWING
O2
in
A
CO2
C
out
NOTE: Since gas
exchange occurs
through
semipermeable
membrane which of
the love above
diagrams offers the
greatest surface area
to volume ratio??
B
I.E Which example would the gas
exchange be most effective??
MULTICELLULAR ORGANSIMS
Consist of many cells with each cell performing
a specialist function
 Groups of cells with special features that
enable them to perform particular tasks
effectively, form tissues
 Cells are formed by cell division
 Cells vary in shape and form

SHAPE AND FORM OF CELLS
Cells vary in their shape and form in order to
diffuse efficiently and maintain an appropriately
balanced internal environment
 We often depict them as simple square (plant
cells) or circular (animal) cells but this is not the
case
 Pge 32 draw nerve, blood and sperm cells
 (the body has 20 types of cells each with its own
unique function- this is called division of labour,
rather like a factory or production line with each
doing its own specific job.
 Show the overhead of different cells if can)

PLEASE NOTE PAGE 28
Viruses
 Light microscopy

 Autoradiography
 Fluorescence
Microscope
 Confocal microscopy
 Electron Microscopes (page 32)