CELL STRUCTURE AND
ORGANELLES
ANIMAL CELL

Electron
micrograph of a
typical animal
cell
Note: mitochondria
in red, nucleus in
peach, endoplasmic
reticulum in blue
Structures in the animal cell
nuclear
1 pore
chromatin
2
nucleus
3
nucleolus
4
rough
5a smooth
5b
endoplasmic
endoplasmic
reticulum
6
ignore
reticulum
microtubule
17
cytoplasm
7
centriole
16
8
vacuole
ribosome
15
14
mitochondria
Golgi9 body
13
lysosome
12
cytoskeleton
vesicle
11
cell10membrane
PLANT CELL
 Electron
micrograph of
a typical plant
cell
Note: mitochondria
in red, nucleus in
green, plastids in
yellow
lysosome
18
Structures in the plant cell
vacuole
17
nuclear
pore 1
chromatin
2
3nucleolus
4
nuclear
membrane
chloroplast
16
ribosomes
5
endoplasmic
microtubule
15
6 reticulum
7
vesicles
8cell membrane
9
cell
wall
microtubule14
10
cytoplasm
13
mitochondria
11 body
Golgi
cell wall 12
CELL MEMBRANE
 Functions
of cell
membrane:
protects cell from
outside environment;
keeps cell contents
together;
selectively allows
materials to cross
into & out of cell.
Cell membrane
CELL MEMBRANE
glycocalyx
transmembrane protein
CELL MEMBRANE


Phospholipid: composed of a phosphate “head”
and fatty acid “tails.”
Hydrophilic Head is “water loving” or soluble in water.
Hydrophobic Tails are “water hating” or insoluble in water.
Hydrophilic head
Hydrophobic tail
Proteins:
“float” around within the membrane or on its surface;
functions include:
structural support
surface binding sites for molecules like hormones
recognition sites for cell to cell communication & interaction
transport molecules across the membrane
transport electrons & protons within the membrane
Cell Membrane
Glycocalyx:
carbohydrate chains attached to proteins (glycoproteins),
involved in recognition & communication proteins,
points for cell to cell attachment
Cholesterol:
keeps the phospholipids stable and helps retain the
membrane‘s shape
MITOCHONDRIA




Mitochondria are the site of
aerobic cellular respiration
Cellular respiration is the
process that converts sugar
energy into adenosine
triphosphate (ATP) for
storage
(overall reaction: glucose + O2
 CO2 + H2O + ATP energy)
ATP is used by other organelles
& cell processes for energy
MITOCHONDRIA



outer membrane – protects and
controls entry of materials
inner membrane –
folded into cristae
intermembrane space
cytosol containing ions
MITOCHONDRIAL STRUCTURES



Cristae: site of
chemical reactions
using embedded
proteins
Matrix:
mitochondrion
cytosol
Mitochondrial DNA:
self replicating
organelle, produces
its own unique
proteins
CHLOROPLASTS



Chloroplasts are found
only in green plants
They convert sunlight to
chemical energy via
photosynthesis
(sunlight + CO2 + H2O
--> glucose + O2)
CHLOROPLAST STRUCTURES





Stroma: chloroplast cytosol
Lamella: membrane that
attaches inner chloroplast
structures
Thylakoid disk: have a
specialized membrane for
photosynthesis
Grana: stack of thylakoid
discs
Chloroplast DNA: selfreplicating organelle
NUCLEUS

Electron
micrograph of a
nucleus
Note: nucleolus in
center of nucleus,
endoplasmic
reticulum and
ribosomes just outside
of nucleus
COMPONENTS OF THE NUCLEUS



Nucleolus: the densest area within the nucleus;
the location for production of ribosomes
Chromatin: stringy material made of proteins and DNA
that makes up the majority of the nucleus
Chromosomes: just before the cell divides thechromatin
condenses into chromosomes
NUCLEUS
CHROMATIN AND CHROMOSOMES
chromatin
chromosomes
RIBOSOMES


Ribosomes are
microscopic
spheres attached to
the ER or freefloating in the
cytoplasm
Ribosomes are
protein factories
ENDOPLASMIC RETICULUM



The ER is a twisting
network of canals and sacs
extending through the
cytoplasm and connecting
the cell membrane to the
nuclear membrane
The ER may have
ribosomes attached to it
(rough ER)
The ER serves to transport
products (e.g. proteins)
within the cell
GOLGI APPARATUS



The Golgi bodies are sacs of
membranous plate-like bags
which produce vesicles (sacs)
They function to produce and
store cellular secretions
Many proteins and lipids
undergo final processing in
the Golgi complex
LYSOSOMES


Membrane bound sacs
that are used for
digestion of various
structures within the
cell
An acidic environment
along with hydrolytic
enzymes within
lysosomes help to
digest particles
CILIA AND FLAGELLA

Both are made of fine protein fibres

Both can be used for locomotion


Cilia: short, may be numerous on cell
surface
Flagella: long, usually few in number
on cell surface
Questions from textbook
 Microscope drawings
 Microscope problems
