Download Vacuoles

Vacuoles and cytoplasm
A vacuole is a membrane bound organelle
which is present in all plant and fungal cells
and some animals and bacterial cells.
The vacuole enlarges on entry of water from
the cytosol
Vacuoles
 The vacuole is the biggest parts of the cell.
 The vacuoles are found in the cells of
plants,protist and some primitive animals.
Vacuole is the cavity of a cell,surrounded by
single membrane and contains fluid,food and
or metabolic wastes.
Structure of vacuole
a.
Vacuoles are irregular in shape.
b. Vacuoles are bubble like sacs bounded by a single unit
membrane called tonoplast. The tonoplast like the
plasma membrane, is differentially permeable.
c.
They are filled with a fluid called cell sap. This includes
minerals, sugars, amino acids.
Types of vacuoles
1. Sap vacuole: They contains cell sap. They are the most
common type of vacuoles.
2. Contractile vacuole: These are special type of vacuoles
that appear and disappear at intervals to get rid of excess
water.
3. Gas vacuole: They contain metabolic gases.
4. Food vacuole: They contain food particles taken up from
the environment.
5. Extrusomes : They contain specialised secretary structure
for food capture.
Functions of vacuoles
• The vacuole stores materials like
water,food,nutrients and waste products.
• Destroys bacterial intruders,stores helpul bacteria.
• Vacuoles stores ions and compounds that cannot
be satisfactorialy stopped in the cytoplasm.
• Protozones and animal cells vacuoles have
osmoregulatory,digestive and defensive role.
• Balances the pH value of the cell.
Cytosols
The cytosol with the cell membrane in the
eukryotic cells,the part of the cytoplasm.It
also comprises with the
mitochondria,plastids and other organelles.
The cell nucleous is separate.
Components of Cytosols
• T he primary component of cytosol is
water.water makes up 70% of a cell to
dissolve other components.
• Protiens and other macromolecules will
dissolve in cytosols.
• Enzymes,which are biological catalyst are
often found in the cytosol in order to speed
up chemical reaction in the cell.
• It also contains ions and inclusion bodies.
Functions of cytosols
• As we know that cytosols has enzymes that takes
molecules and break them down,so that indvidual
organelles can use them as they need to.
• The enzymes also speed up chemical reactions
within the cells
• Cytosols also contain cytoskeleton which gives the
cells its shapes and can help in the movement of
cell.
• Protiens with the cytosols plays an important role in
signal transduction path ways and glycolysis and
enables protien synthesis.
Submitted to
Prof. Shiffali mam
Submitted by
Komal(838/15)