Download function of cell

CELL
STRUCTURES
AND CELL
ORGANISATION
CELLS =
BRICKS
Have you noticed how workers at a
construction site lay bricks to build the
walls of a house ?
Just as the walls of a house are made
of bricks, livings organisms are made
of basic units called cells.
They form the building blocks of all
living organism.
• Generally cell can
be divided to two
types, plant cell and
animal cell.
• Both animal and
plants cells consist
of
cytoplasm,nucleus
and surrounded by a
thin layer of plasma
membrane.
WHAT IS ORGANELLE?
The cytoplasm contains structures
called organelles.
Organelles perform specific functions
which enables the cell to function as a
unit of life.
Besides the nucleus, other examples of
organelles include mitochondria,
chloroplast, vacuoles, ribosomes,
lysosomes and the Golgi apparatus.
cell membrane
•
•
•
•
Refers to all the membranes found
inside the cell
the membrane at the surface which
encloses the content of a cell is called
plasma membrane.
made of proteins and phospholipids
separates the content of a cell from the
outer environment.
semi-permeable and regulates the
movement of substances into and out
of the cytoplasm.
cell wall
• Rigid outer layer that surrounds the
plasma membrane of plant cells
• composed of cellulose,a a tough and
fibrous carbohydrate
• permeable to all fluids
• gives shape to a plant cell
• provides mechanical support
• protection from rupturing
cytoplasm
• region between the nucleus and the
plasma membrane.
• jelly-like matrix in which organelles
are suspended.
• acts a a medium for biochemical
reactionsin the cell.
• provides substances obtained from the
external environment to the organelles.
organelles and
their functions
nucleus
• large,dense and spherical organelle
enclosed by nuclear membrane
• contain nucleolus, chromatin @
chromosome and nucleoplasm
• choromosomes carry genetic
information
• controls all the activities which take
place in the cell
vacuole
• fluid-filled sac surrounded by
tonoplast
• contain cell sap
• plant cell contain more vacuole
compared with animal cell
• helps to regulate water balance
• acts as a storage place in a cell
• support herbaceous plant
mitochondria
• small spherical organelles
• involved in cellular respiration
• store energy in the form of ATP
ribosomes
• compact spherical organelles found
attached to the surface of the rough
endoplasmic reticulum or suspended
freely in the cytoplasm
• contains two subunits,comprises a type
of ribonucleic acid (RNA) and protein
• synthesis protein
endoplasmic
reticulum
• physically continuos with the nuclear
membrane
• two types: rough ER and smooth ER
• RER: transport protiens made by
ribosome
• SER: the site of important metabolic
reactions,including synthesis of lipids
golgi apparatus
• functions as a processing, packaging
and transporting centre of
carbohydrates, proteins, phospholipids
and glycoproteins
lysosomes
• membrane-bound
sacs that contain hydrolytic enzymes
• eliminate worn out
mitochondria and
others damaged
organelles
• digest bacteria by
breaking
down the bacteria
cell wall
centrioles
chloroplasts
• typically lens-shaped
• contain green pigment chlorophyll
• chlorophyll traps sunlight and convert
light energy to chemical energy during
photosynthesis