5. Nuclear Envelope
Membrane of the nucleus
Consist of two lipid bilayers folded together as a single
membrane
Different kinds of membrane proteins are embedded in
the two lipid bilayers. Some are receptors and
transporters.
Fibrous proteins that attach to the inner surface of the
nuclear envelope anchor DNA molecules and keep
them organized. During cell division, these proteins help
the cell parcel out the DNA into its offspring.
6. Chromosomes
Chromatin is the name for all of the DNA, together with its
associated proteins, in the nucleus.
Each molecule of DNA, together with its many attached
proteins, is called a chromosome.
Do you know that chromosomes change in appearance
over the lifetime of a cell ?
8. The energy mechanism !!
We all know that every action requires energy
This energy is stored in the form of ATP.(ADENOSINE It
is produced in the mitochondria through the process of
oxidative phosphorylation.
THEY ARE FOUND IN HIGH CONCENTRATIONS IN THE
MUSCLE CELLS THAT REQUIRE MORE ENERGY.
Although the primary function of mitochondria is to
produce energy, they also play an important role in the
metabolism and synthesis of certain other substances in
the body
9. NEWSPAPER ARTICLE 1-
Scientists at the University of California in Davis (UCD) demonstrate
in a new study that children with autism are also highly likely to
suffer from defects in their mitochondria, which are structures
generally refer to as the “power plants” of the cell.
JUST LIKE HOW THE BRAIN IS THE 2ND –LARGEST ENERGY
CONSUMING ORGAN it stands to reason that not
providing sufficient FUEL(ENERGY) for neurons to function
properly may lead to impaired capabilities and AUTISM is
the physical CAUSE Of this neural “starvation.”
According to this report Children with mitochondrial
diseases may present exercise intolerance, seizures and
cognitive decline, among other conditions
evidence of mitochondrial dysfunction and changes in
mitochondrial DNA were detected in the blood of these
young children with autism.
10. CURING MIROCHONDRIAL DEFECTS
!!!!!!
TO DIAGONISE mitochondrial dysfunction WE NEED TO
CARRY OUT A MUSCLE BIOPSY !
ARGHHHHHHHHHHHH WHATS THAT ! ????????????????
a muscle biopsy is a procedure in which a piece of muscle
tissue is removed from an organism and examined
microscopically. A biopsy needle is usually inserted into a
muscle, where a small amount of tissue remains
A muscle biopsy can lead to the discovery of problems with
a nervous system, which leads us to knowing the problems
that has occurred in our body due to the defects in the
mitochondria.
11.
12. The Endomembrane System
A series of interacting organelles between the nucleus
and the plasma membrane
Main function : Make lipids, enzymes, and proteins for
secretion or insertion into cell membranes. Also destroys
toxins and recycle wastes.
13. Endoplasmic Reticulum (ER)
An extension of the nuclear envelope
Forms a continuous compartment that folds over and
over into flattened sacs and tubes
There are two types ;
1. Rough ER
2. Smooth ER
14. Vesicles
Small, membrane-enclosed, sac-like organelles. Form in
great numbers, in a variety of types.
Transports substances from one organelle to another, or to
and from the plasma membrane.
Others, like peroxisomes, contains enzymes that digest fatty
acids and amino acids. Can also inactivate hydrogen
peroxide, a toxic by-product of fatty acid breakdown.
Later, enzymes in the peroxisomes convert hydrogen
peroxide to water and oxygen or they use it in reactions that
break down alcohol and other toxins.
15. DO YOU KNOW?
Drink alcohol, and the peroxisomes in your liver and
kidney cells degrade nearly half of it !!
16. Peroxisomes
• Organelle with multifaceted functions
• Responsible for a multitude of metabolic functions within cells.
• They contain over 50 different functional enzymes capable of
forming highly variable structures adapted to the specific needs of
the organism.
• One of the most important features of peroxisomes is the spatial
isolation (compartmentalization) of metabolic pathways in which
poisonous hydrogen peroxide is formed.
• Its destruction therefore is one of the most important functions of
the peroxisomes.
17. • Because hydrogen peroxide is harmful to the cell, peroxisomes also
contain the enzyme catalase, which decomposes hydrogen peroxide
either by converting it to water or by using it to oxidize another organic
compound.
• A variety of substrates are broken down by such oxidative reactions in
peroxisomes, including uric acid, amino acids, and fatty acids.
• The oxidation of fatty acids is a particularly important example, since it
provides a major source of metabolic energy. In animal cells, fatty acids
are oxidized in both peroxisomes and mitochondria, but in yeasts and
plants fatty acid oxidation is restricted to peroxisomes.
19. Peroxisomal disorders
Illnesses due to peroxisomal defects are usually fatal
Zellweger Spectrum
So severe that the patients die during infancy
20. PROTEIN SYNTHESIS MECHANISM – THE
RIBOSOMES
Ribosomes are organelles that consist of RNA and
proteins. They are responsible for assembling the
proteins of the cell.
Depending on the protein production level of a
particular cell, ribosomes may number in the millions.
21. The protein making mechanism
A ribosome is a component of cells that assembles
the twenty specific amino acid molecules to form the
particular protein molecule determined by
the nucleotide sequence of an RNA molecule.
THE CENTRAL DOGMA OF BIOLOGY – we learned thIs
! REMEMBER !!!!
22. Diamond blackfan Anemia
Diamond Blackfan anemia (DBA) is an inherited red cell
aplasia caused by mutations in one of several r-proteins.
One of the proteins would be the RPS19 protein.
The RPS19 protein is involved in the production
of RIBOSOMES. As such, loss of RPS19 function would be
predicted to affect translation and Protein biosynthesis and
have a much broader impact.
Disease features may be related to the nature of
RPS19 mutations.
The disease is characterized by dominant inheritance, and
therefore arises due to a partial loss of RPS19 protein
function
23. Lysosomes
Vesicles that contain powerful digestive enzymes.
Serve as waste disposal and recycling centers
Enzymes inside them break large molecules into smaller
subunits that the cell can use as building material or
eliminate.
Different kinds of molecules are broken down by different
lysosomal enzymes
24. Lysosome malfunction
In some people, a
genetic mutation
causes a deficiency
or malfunction in one
of the lysosomal
enzymes
As a result, molecules
that would normally
get broken down
accumulate instead.
25.
26.
27.
28.
29.
30. Tay-Sachs Disease
Enzyme responsible for ganglioside break-down misfolds and
is destroyed
Usually, affected infants seem normal for the first few months
Symptoms begin to appear as ganglioside accumulate
higher and higher levels inside their nerve cells
Within 3 to 6 months, the child becomes irritable, listless and
may have seizures. Blindness, deafness and paralysis follow.
Affected children usually die by the age of 5
31. Treatment
Options for treatment are still ongoing.
Potential therapies involve blocking ganglioside synthesis
or using gene therapy to deliver a normal version of the
missing enzyme to the brain.
All treatments are still considered experimental, and Tay-
Sachs is still incurable
32. Golgi apparatus
it was identified in 1898 by the Italian physician Camillo
Golgi, after whom the Golgi apparatus is named.
It processes and packages proteins after their synthesis
and before they make their way to their destination; it is
particularly important in the processing of proteins
for secretion.
Due to its fairly large size, the Golgi apparatus was one of
the first organelles to be discovered and observed in
detail.
33. Interesting facts
Due to its fairly large size, the Golgi apparatus was one of
the first organelles to be discovered and observed in
detail.
Golgi apparatus during mitosis
In animal cells, the Golgi apparatus will break up and
disappear following the onset of mitosis or cellular
division. During the telophase the Golgi apparatus
reappears; however, it is still uncertain how this occurs.
34. Science news article : Artificial Golgi may provide
new insight into key cell structure
Scientists in new york and north carolina have reported to
have assembling the first functioning prototype of an
artificial golgi organelle.
This key structure inside the cell helps to process and
package hormones , enzymes and other substances that
allow the body to function normally.-hence it works
exactly like the real golgi apparatus in our body.
This lap-on-a-chip device could lead to a faster and safer
method in producing heparin.
WHAT IS HEPARIN ? I WILL EXPLAIN !!!
35. CONTINUING….
This device ahs also been tested in labs and it has said to
have quickly and efficiently produced heparin.
It did so in as assembly line fashion which was tested using a
combination of enzymes, sugars and other raw materials.
During this experiment it was shown that this device has a
strong clot fighting potential.
It is believed that in the future, In the case of an golgi
apparatus defect in an individual this “artificial golgi” could
lead to a faster and safer method for producing heparin.
36.
37. Plastids
Membrane-enclosed organelles that function in
photosynthesis or storage in plants and algal cells.
Common types ; chloroplasts, chromoplasts and
amyloplasts
Chloroplasts are found in photosynthetic cells of plants
and many protists.
Nucleus protecting, controlling access to DNAEndoplasmic Reticulum Routing, modifying new polypeptide chains; synthesizing lipids etcGolgi body modifying new polypeptide chains; sorting, shipping proteins and lipidsVesicles transporting, storing or digesting substances in a cellMitochondrion Making ATP by sugar breakdownChloroplast Making sugars in plants, some proteinsLysosome Intracellular digestionPeroxisome inactivating toxinsVacuole StorageRibosomes assembling polypeptide chainsCentriole anchor for cytoskeleton
The nuclear envelope encloses the nucleoplasm, a viscous fluid similar to cytoplasm. The nucleus also contains at least one nucleolus which is a dense, irregular shaped region where subunits of ribosomes are assembled from proteins and RNA. These subunits later pass through the nuclear pores into the cytoplasm, where they join and become active in protein synthesis.
these molecules and structures work as a system to transport various molecules across the nuclear membraneThe thin space between the two layers connects with the lumen of the rough endoplasmic reticulum (RER), and the outer layer is an extension of the outer face of the RER.
When a cell is not dividing, its chromatin appear grainy.Just before a cell divides, the DNA in each chromosome is copied or duplicatedThen, during cell division, the chromosomes condenseFirst threadlike rodlike
Mitochondria are rod-shaped structures that are enclosed within two membranes - the outer membrane and the inner membrane. The membranes are made up of phospholipids and proteins. The space in between the two membranes is called the inter-membrane space which has the same composition as the cytoplasm of the cell.Outer MembraneThe outer membrane is smooth unlike the inner membrane and has almost the same amount of phospholipids as proteinsinner MembraneThe inner membrane is more complex in structure than the outer membrane as it contains the complexes of the electron transport chain and the ATP synthetase complex. It is permeable only to oxygen, carbon dioxide and water. It is made up of a large number of proteins that play an important role in producing ATP, and also helps in regulating transfer of metabolites across the membrane. The inner membrane has infoldings called the cristae that increase the surface area to volume ratio for the complexes and proteins that aid in the production of ATP, the energy rich molecules
BEFORE GOING THROUGH THIS SLIDE YOU GUYS MUST KNOW THAT -One of the main customers the organelles serve is the brain, which consume the second-largest amount of energy in the human body after the heart.Cognitive decline is characterized by a decline in memory, thinking or cognitive function. People experience deterioration in memory and learning, attention and concentration, thinking, use of language, and other mental functions. We show you how to cope.
two kinds of ER are named for their appearance in electron micrographRough ER : numerous ribosomesSmooth : lack of ribo
----- Meeting Notes (11/16/11 21:22) -----also part of the EMS
Proteins destined for peroxisomes are synthesized on free ribosomes and imported into preexisting peroxisomes as completed polypeptide chains. Protein import results in peroxisome growth and the formation of new peroxisomes by division of old ones
Illnesses resulting from biogenetic disorder is known as Zellweger SpectrumSHOW ARTICLE !!
Distinguishing Characteristics:Ribosomes are typically composed of two subunits: a large subunit and a small subunit. Ribosomal subunits are synthesized by thenucleolus. These two units join together when the ribosome attaches to messenger RNA to produce a protein in the cytoplasm.
is that DNA is used to make RNA, which is used to make proteins. The DNA sequence in genes is copied into a messenger RNA (mRNA). Ribosomes then read the information in this mRNA and use it to create proteins. This process is known as translation; the ribosome translates the genetic information from the RNA into proteins. Ribosomes do this by binding to an mRNA and using it as a template for determining the correct sequence of amino acids in a particular protein. The amino acids are attached to transfer RNA (tRNA) molecules, which enter one part of the ribosome and bind to the messenger RNA sequence. The attached amino acids are then joined together by another part of the ribosome. The ribosome moves along the mRNA, "reading" its sequence and producing a corresponding chain of amino acids.Ribosomes are made from complexes of RNAs and proteins called ribonucleoproteins. Ribosomes are divided into two subunits. The smaller subunit binds to the mRNA, while the larger subunit binds to the tRNA and the amino acids. When a ribosome finishes reading a mRNA, these two subunits split apart. Ribosomes have been classified as ribozymes, because the ribosomal RNA seems to be most important for the peptidyltransferase activity that links amino acids together.
In the Lysosomes, or Recycling Center of the Cell, our Penguins work hard and efficiently to move large bags of undegraded compounds, or substrates (denoted by the "S" on each bag). Each bag is broken down and sent back to the body to be reused.
In some people, our penguins can't do their job efficiently because of a genetic defect that prevents the bags of waste from moving through the Recycling Center. Most commonly, this defect is found in the enzyme whose job it is to bust up certain bags of substrates. The result is a slowdown in the workflow, resulting in substrates not moving through the Lysosome.
Over time work in the Recycling Center comes to a virtual standstill and the bags of substrates begin to build up in the Lysosomes. When this happens the person affected displays a multitude of symptoms that cause pain, neurological damage and a shortened lifespan.
You look at this child. She looks normal but actually, she suffers from TaySacchs disease
(stage where meiosis and mitosis occurs) – TELOPHASE !
What is heparin ?It is an widely used anticoagulant or actually known as a blood thinner. This chemical substance which is produced by the golgi apparatus helps in the clotting of the blood
