Asian American Pacific Islander Month DDSD 2024.pptx
Vacuole ppt
1.
2. • vacuole was first
observed in protozoa.The
contractile vacuole or
stars of many protozoa
were seen by Lazzaro
Spallanzani in 1776
although he mistook them
respiratory oragan
3. Discovery of vacuole
In 1841 when Felix Dujardin
first discovered vacuole
under a compound
microscope while observing
a plant cell noticed something
that took up most of the space
in the cell.
He named it
vacuole" which comes from
the Latin word "vacuus"
which means "empty.
because it appear empty in
light microscopand.
Little did he know how
untrue this was, because the
truth is, it is not empty. It
contain cell sap.
5. Tonoplast
• The structure of the vacuolar
membrane (tonoplast) was studied in
red beet roots. The vacuolar
membrane was shown to be
composed of highly ordered lipids
which form regions of free liquid lipid
bilayer loosely bound to integral
proteins.
6. Composition of cell sap
• Cell sap consists of water and various substances
that are often in the form of a colloidal suspension.
•
• On the average, cell sap has twice the viscosity of
water. In dormant seeds and spores the cell sap
dehydrates, hydrating again upon germination.
• Young cells have less cell sap than older ones.
7. • Cell sap contains the carbohydrates glucose,
fructose, sucrose and inulin ,pectins glycosides
,tannins.
• The composition of cell sap is specific to families
and even to species.
• depending also on;
• growth conditions.
• the age of the plant.
8. Types of Vacuole
Vacuole in organisms cell can be of various
types:
• And in some bacterial cells.
• And fungal cells.
• It is present in in all plant cells.
9. • Vacuoles in fungal cells
Vacuoles in fungal cells
perform similar functions
to those in plants and
there can be more than
one vacuole per cell.
• . The fungi vacoule play
role in homeostasis of
cell pH and the
concentration of
ions, osmoregulation,
storing amino acids and
polyphosphate.degradativ
e processes.
10. Central Vacuole In Plant Cells
.
• The central vacuole is a membrane-bound organelle
containing water and other enzymes that function during the
life of the plant.
•the central vacuole is surrounded by a phospholipid
bilayer.
•The size and shape of the central vacuole depends on the
type of cell they are in and their specific function.
11.
12. Functions Of The Vacuole
Vacuoles can be large organelles occupying
between 30% and 90% of a cell by volume.
Vacuoles appear to have three main functions,
they;
i. contribute to the rigidity of the plant using water to
develop hydrostatic pressure
ii. store nutrient and non-nutrient chemicals
iii. break down complex molecules.
13. • Isolating materials that might
be harmful or a threat to the
cell
Containing water in plant
cells
Maintaining internal
hydrostatic pressure or turgor
within the cell maintaining an
acidic internal pH
Functions of plant vacuole
14. Allows plants to support
structures such as leaves
and flowers due to the
pressure of the central
vacuole
In seeds, stored proteins
needed for germination are
kept in 'protein bodies',
which are modified
vacuoles
15. Flexible
space but never empty space:
•A membrane barrier called a tonoplast limits each vacuole.
•This membrane is remarkable in that it can surround a small
amount of fluid, and stretch to become an organelle occupying
as much as 95% of the cell by volume.
•In this process all the other organelles in the cell are pressed,
without damage, against the firm cellulose cell wall.
16. The state of plant cell vacuoles indicates whether
you need to water your garden:
A cell in which the vacuole contains all the water it needs
is said to be in a turgid state.
A state of wilt shows a shortage of water and a cell is said
to have lost its turgor.
17.
18. Vacuole assist with growth:
The relatively high hydrostatic pressure produced by vacuoles
also assists in cell elongation but only when the cell wall is
made soft enough for extension to take place.(during growth)
The vacuolar membrane works as a proton
pump:
vacuolar membrane works as a proton
pump and uses energy from adenosine
triphosphate(ATP).Maintain acidity of
vacuole.
19.
20. Chemicals help create ‘cell pressure’
Chemicals in the vacuole forming a concentrated
solution create the hydrostatic pressure produced within
plant cells.
Some of these chemicals form ions and the effect of this
system is to create a high osmotic pressure.
Water enter the vacuole maintaining internal turgidity.
21.
22. • As plants lack
immune cells, each
cell has to defend
itself against invading
pathogens.
• Plant cells have a
large central vacuole
that accumulates a
variety of hydrolytic
enzymes and
antimicrobial
compounds, raising
the possibility that
vacuoles play a role
in plant defense.
23. The vacuolar membrane is a selective membrane:
The vacuolar membrane or tonoplast is a selective
membrane and the passage of chemicals through it is
controlled in both directions.
. Isolating harmful materials
Plants, unlike animals, do not have a well-developed
excretory system but they do have vacuoles. Isolating
materials that might be harmful or a threat to the cell .
24. Vacuoles – an endowment for the next
generation:
Proteins, fats and carbohydrates can be safely stored in the
vacuoles of storage cells in seeds for many years for
utilisation when germination takes place.
Vacuoles and lysosomes have similar
functions:
Vacuoles in plant cells are in some respects the equivalent
of lysosomes in animal cell . The ‘breakdown products’ are
retained within the vacuole.
25. Autophagy
• Autophagy is an process by which
cytoplasmic components are selectively
enclosed within a double-membrane
vesicle known as the autophagosome .
• Delivered to the vacuole for degradation of
components and recycling of needed
nutrients,or orgenelles.
26. Autophagy
One of the biggest functions
of the vacuole is their role in
autophagy.
Autophagy is the
degradation of unnecessary
cells .
Vacuoles maintain a balance
between biogenesis
(creation) and degradation
(removal).
27. Formation of vacuole in plant
Plant cell form by cell
devision of shoot and root
merismetic have hundred
of small provacuoles
which arise by budding
and fusion of Golgi
network .
At this point in
development plant
vacuole resemble animal
lysosomes both in size
and quantity
28. • As growth of cells
progress the provacuoles
start to fuse together and
start to form single
centeral vacuole.
• All the orgenelles of cell
start to push towards the
cell memberane .
Orgenelles are between
the tonoplast and cell
memberane.
29. Function Of Contractile vacuole
Water is constantly entering the
cell by osmosis.
The water on the outside is
hypotonic and the water on the
inside of the organism is
hypertonic .
the contractile Vacuole is
needed which acts as a pump to
remove excess water without
this the cell would burst from to
much excess water.
30. Function Of Food Vacuole
A food vacuole is a
membrane-bound vacuole
where ingested food is
stored, and eventually,
digested. The food contained
within the vacuole is taken up
by the process of
phagocytosis.
31. • Who discover plant vacuole?
• Who named vacuole?
• from where plant vacuole originate?
• How vacuole maintain tergidity in plant?
• What are provacuole and how form?
• Which orgenelle of animal similer to provacuole of
plant?
Questions
