The
cytoplasm is a semi-liquid goo that contains a eukaryotic
cell's organelles. The organelles perform specific functions
for the cell. Note that some cells (bacteria) do not
have organelles and are prokaryotic.
All
of the organelles except the ribosome are bounded by
a membrane. Two of the organelles (the nucleus and the
mitochondria) are bounded by two membranes. Study the
following picture of a eukaryotic cell and its organelles,
as well as the list of organelle functions that follows
it.
|
Organelle |
Function |
|
Vacuole |
Storage
of wastes and other material |
|
Ribosomes |
Sites
of protein synthesis. Not bound by membrane |
|
Smooth
endoplasmic reticulum |
System
of membranes and tubes that transport substances
around the cell. |
|
Rough
endoplasmic reticulum |
Endoplasmic
reticulum with ribosomes bound to it. Ribosomes
on the rough ER specifically synthesise membrane
proteins or secreted proteins. |
|
Golgi
apparatus |
Sorts
and packages proteins made by ribosomes on the
rough ER. |
|
Mitochondria |
Function
in cellular respiration. |
|
Lysosomes |
Digest
foreign substances and worn out organelles. |
|
Centrioles |
Help
to form substances and worn out organelles. |
|
Nucleus |
Control
center of the cell, contains genetic material
(DNA). |
| Nucleolus |
Small,
dense structure in the nucleus, site of ribosome
synthesis. |
| Cell
membrane |
Outer
membrane that regulates what comes into and out
of the cell. |
