This presentation covers cells, its functions, membrane lipids, membrane proteins, and plasma membrane.

1. CELLS
Report by: Veronica Baje

2. CELLS
• A cell is the structural and functional
unit of life.
• Each cell contains smaller organelles
that perform various functions such
as metabolism, transportation and
secretion of substances. Because
some cells perform specific
functions, they have special
modified structures.

3. FUNCTIONS OF THE CELL
1. Provide Structure and Support
2. Facilitate Growth through Mitosis
3. Allow Passive and Active Transport
4. Produce Energy
5. Create Metabolic Reactions
6. Aids in Reproduction

4. PLASMA MEMBRANE
• The cell membrane (also
known as the plasma
membrane (PM) or
cytoplasmic membrane, and
historically referred to as the
plasmalemma) is a biological
membrane that separates
the interior of all cells from
the outside environment
(the extracellular space)
which protects the cell from
its environment.

5. MEMBRANE LIPIDS
• Membrane lipids are a group
of compounds (structurally
similar to fats and oils) which
form the double-layered
surface of all cells (lipid
bilayer). The three major
classes of membrane lipids
are phospholipids,
glycolipids, and cholesterol.

6. THREE MAJOR CLASSES OF MEMBRANE
LIPIDS
• PHOSPHOLIPIDS – are a class of lipids that are a major
component of all cell membranes. They can form lipid
bilayers because of their amphiphilic characteristic. The
structure of the phospholipid molecule generally consists of
two hydrophobic fatty acid "tails" and a hydrophilic "head"
consisting of a phosphate group.
• GLYCOLIPIDS – are lipids with a carbohydrate attached by a
glycosidic (covalent) bond. Their role is to maintain the
stability of the cell membrane and to facilitate cellular
recognition, which is crucial to the immune response and in
the connections that allow cells to connect to one another to
form tissues.
• CHOLESTEROL – is a waxy, fat-like substance that is found in
all the cells in the body. The body needs some cholesterol to
make hormones, vitamin D, and substances that help digest
foods.

7. MEMBRANE PROTEINS
• A membrane protein is
a protein molecule that
is attached to, or
associated with, the
membrane of a cell or
an organelle.
Membrane proteins can
be put into two groups
based on how the
protein is associated
with the membrane.

8. TWO GROUPS OF MEMBRANE PROTEINS
• INTEGRAL MEMBRANE PROTEIN – are
permanently embedded within the plasma
membrane. They have a range of important
functions. Such functions include channeling or
transporting molecules across the membrane.
• PERIPHERAL MEMBRANE PROTEIN – are proteins
that are only temporarily associated with the
membrane. They can be easily removed, which
allows them to be involved in cell signaling.
Peripheral proteins can also be attached to integral
membrane proteins, or they can stick into a small
portion of the lipid bilayer by themselves.