Physiology 2130 Lecture Notes - Lecture 3: Endoplasmic Reticulum, Secretion, Golgi Apparatus
21 May 2018
School
Department
Course
Professor
Physiology 2130: Human Physiology
Page 1
MODULE 3: Human Cell
find more resources at oneclass.com
find more resources at oneclass.com
Physiology 2130: Human Physiology
Page 2
Basic Cell Organelles
A. Golgi Apparatus
The Golgi Apparatus is responsible for
packing proteins from the rough
endoplasmic reticulum into membrane-
bound vesicles. Two types of vesicles are
produced by the Golgi bodies: secretory
vesicles, which transport proteins to the cell
membrane for release into the extracellular
environment; and storage vesicles such as
lysosome, whose contents are stored within
the cell.
B. Secretory Vesicle
Secretory vesicles are produced by the Golgi
apparatus and are used to transport various
types of proteins out of the cell for use in
other parts of the body. The process by
which the cell releases proteins through the
membrane into the extracellular environment
is, not surprisingly called secretion.
C. Free Ribosomes
Ribosomes are dense granules of RNA and
protein. They are responsible for
manufacturing proteins from amino acids
under the control of the cell’s DNA. There
are two types of ribosomes, which are
attached to the endoplasmic reticulum; and
free ribosomes, which float in the cytoplasm.
Free ribosomes often form in groups of 10 to
20 known as polyribosomes
D. Lysosomes
Lysosomes are one type of storage vesicle produced by the Golgi apparatus. Lysosomes act as the digestive
system of the cell. They contain several kinds of enzymes that are used by the cell to destroy damaged
organelles, kill bacteria, and break down other kinds of biomolecules.
E. Mitochondria
F. Endoplasmic Reticulum
The endoplasmic reticulum is a continuation of the cell’s nuclear membrane and is the site for the synthesis,
storage and transport of proteins and lipid molecules. There are two types of ER, rough or granular ER which
is covered with rows of ribosomes, and smooth or agranular ER which lacks ribosomes. Rough endoplasmic
reticulum is the site of protein synthesis and smooth endoplasmic reticulum is responsible for the synthesis of
lipids and fatty acids. Proteins manufactured in the rough endoplasmic reticulum are packaged into vesicles
that transport them to Golgi apparatus.
G. Cell Membrane
The primary function of the plasma membrane is to regulate the passage of substances into and out of the
cell. Allowing certain molecules to cross the membrane while excluding other molecules. The structure of the
plasma membrane and the mechanism by which the membrane regulates transport discussed elsewhere in
the module. The membrane also plays an important role in detecting chemical signals from other cells and in
forming physical links with adjacent cells.
H. Centriole
Centrioles are cylindrical bundles of microtubules that are responsible for directing the movement of DNA
strands during the process of cell division.
I. Nucleolus
The nucleolus is a dense body within the cell nucleus which contains the specific DNA that produces the RNA
found in ribosomes.
find more resources at oneclass.com
find more resources at oneclass.com
Physiology 2130: Human Physiology
Page 3
find more resources at oneclass.com
find more resources at oneclass.com
Document Summary
The golgi apparatus is responsible for packing proteins from the rough endoplasmic reticulum into membrane- bound vesicles. Two types of vesicles are produced by the golgi bodies: secretory vesicles, which transport proteins to the cell membrane for release into the extracellular environment; and storage vesicles such as lysosome, whose contents are stored within the cell. Secretory vesicles are produced by the golgi apparatus and are used to transport various types of proteins out of the cell for use in other parts of the body. The process by which the cell releases proteins through the membrane into the extracellular environment is, not surprisingly called secretion. Ribosomes are dense granules of rna and protein. They are responsible for manufacturing proteins from amino acids under the control of the cell"s dna. There are two types of ribosomes, which are attached to the endoplasmic reticulum; and free ribosomes, which float in the cytoplasm. Free ribosomes often form in groups of 10 to.
