Transcript File - Chapter 6: The Cell

• Cells cannot be seem by unaided eyes.
• The first microscope were invented during
the Renaissance and were improved
during the 17th century.
• There are different types of microscope
that were used to see objects and
materials of the range from 100um to
.1nm.
Light Microscope (LMs)
•The lenses refract or bend
the light in a way that it is
projected into the eye.
•Range from 1cm to 100nm
Electron Microscope (EMs)
Scanning electron
Transmission
Microscope
Electron
(SEM)- scans the
Microscope (TEM)
surface of object
– scan the internal
range from100 um untrastructure of
to .1nm.
cells.
• What is cell fractionation????
The process of separating the cell from
it’s organelles
The most powerful machine that is used in
this process is called ultracentrifuge.
Sim. And Dif. Of Eukaryotic and
Prokaryotic cells
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The nucleus houses most of the cell’s DNA.
Most conspicuous organelle in eukaryotic cells.
It is enclosed by a nuclear envelope separating it from
cytoplasm.
The nuclear envelope is a double membrane, each lipid bilayer
with associated proteins.
The envelope is perforated by pores and each pores of in the
inner and outer nuclear envelope are continuous.
Pore complex regulate substances that comes in and out of the
nuclear envelope.
The nuclear envelope is lined with netlike array of protein
filament that maintain it’s shape and supporting the nuclear
envelop is called the nuclear lamina.
Within the nucleus there are chromosomes.
Each chromosomes are made up of chromatin.
When the cell is prepared to divide it coil up and separate into
chromosomes.
Within the nucleus, lies the nucleolus.
Ribosomal RNA is being synthesized that exits the cytoplasm.
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Ribosomes are used to make proteins
Ribosomes are made from ribosomal RNA and
proteins, and carry out protein synthesis.
Ribosomes are not enclosed in membranes.
Ribosomes build proteins in two cytoplasmic
locales.
There are two types of ribosomes: Free
ribosomes and bound ribosomes.
Free Ribosomes are suspended in the cytosol.
Bound ribosomes are attached to the outside of
the endoplasmic reticulum or the nuclear
envelope.
Most of the proteins are made of free ribosomes.
Bound ribosomes make proteins that are
destined either insertion or for export from the
cell.
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Different membrane in
eukaryotic cells are part of
the endomembrane system
that carries out variety of
tasks in the cell.
Relate through direct
physical continuity or
transfer of membrane
segments as tiny vesicles.
The endomembrane system
includes the nuclear
envelope, endoplasmic
reticulum, Golgi apparatus,
lysosomes, vacuoles, and
plasma membrane.
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Account more than half of the membrane in
eukaryotic cells.
Consist of tubules and sacs called cristernae.
ER lumen separate the internal compartment of the
ER.
Two kinds of distinct: Rough ER and Smooth ER
Smooth ER lack ribosomes.
Rough ER contain ribosomes.
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Functions in diverse metabolic processes.
Such as synthesis of lipids, metabolism of
carbohydrate, and detoxification of drugs
and poison.
The enzyme help synthesis, metabolize,
and detoxifies.
Steroids are produced the smooth ER.
Detoxification happens often in the liver
cells.
It involve adding hydroxyl groups to drugs,
making them easier to flush through the
body.
Stores calcium ions (occurs in muscle
cells).
EX: smooth ER membrane pumps
calcium ions from the cytosol to the ER
lumen. When the muscle cell stimulates
by nerves pulses, calcium ion rush back
across the ER into the cytosol and trigger
contraction of the muscle cell.
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Specialized cells that secrete proteins are produced by the ribosomes in the
rough ER.
Most of the secreted proteins are glycoproteins.
Once secretory proteins are formed in the ER, the membrane keep them
separated from proteins and ribosomes that remains in the cytosol.
Then tiny membranous sacs in the cell of the cytoplasm carries to the
molecules that are produced by the cell called transport vesicles.
Rough ER makes it’s own phospholipids because the enzymes that are built
into the ER membrane assemble phospholipids from the precursors in the
cytosol.
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Transport vesicle travel through the Golgi
apparatus.
Product of the ER are modified and stored and
sent to other organelles.
Consist of flattened membranous sacs, look
like stacks of pita bread.
Vesicle concentrated in the vicinity of the Golgi
apparatus are engaged in the transfer of
material between the parts of the Golgi.
Golgi stack are polar to the membrane of the
cristernae.
The two poles are cis face and trans face.
Cis face is located near the ER that transport
vesicle material from the ER to the Golgi
apparatus.
Vesicle buds from the ER add membrane and
lumen to the cis face by fusing with a Golgi
membrane.
Trans face give rise to vesicle that pinches off
and travels to other sites.
Manufacture certain macromolecules.
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It is a membrane sac if hydrolytic enzymes that animal cell uses to digest macromolecules.
Work best in acidic environments.
If lysosomes break open they are not active anymore because the cytosol become neutral
and if it leak too much then it destroys a cell.
It is made by rough ER and then transferred to the Golgi apparatus.
Some arise from budding from trans face of the Golgi apparatus.
It carries out digestions and recycle it’s own organic material a process called autophagy.
autophagy occurs when a damaged organelle or cytosol become surrounded by a membrane,
lyososme fuses with the vesicle and the enzyme dismantle the material and organic
monomers and the cell renew itself.
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Vacuole carry out hydrolysis that is
similar to lyososmes.
Food vacuoles are formed by
phagocytosis.
Fresh water protists have contractile
vacuole, a membranous ac that helps
move excess water out of certain cells
Mature plant cells contain large
central vacuoles enclosed my a
membrane called tonoplast.
Central vacuole is developed by
smaller vacuoles derived from the ER
and Golgi apparatus.
Tonoplast is selective in transporting
solute.
Plant vacuole holds important organic
compounds and plants main
repository of organic ions.
Major role in growth that enlarge as
their vacuole absorb water.
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it is the site of cellular respiration
Create ATP for the cell
It is called the power house because it
create energy or ATP for the cell.
They are found in every eukaryotic cells.
It is enclosed by two membranes, each a
phospholipids bilayer with unique
embedded protein.
The outer membrane is smooth but the
inner layer is convoluted embedded with
cristae.
The inner membrane divide the
membrane into two internal
compartment,
The first internal membrane contain
space and is the region between inner
and outer membrane.
The second is the compartment called
the mitochondrial matrix that is enclosed
by the inner membrane.
The matrix contain many enzyme that
carries out cellular respiration.
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it is present in plant cell that give rise to the process
called photosynthesis.
Convert solar energy to chemical energy.
Contain green pigment chlorophyll with enzyme and
molecules that help function in the photosynthetic
production of sugar.
Consist of two membrane with a very narrow
intermembrane space,
Inside the membrane there are interconnect sac called
thylakoid,
When they thylakoid are stack together they are called
granum.
The fluid inside the thylakoid are is stroma which
contain chloroplast DNA and ribosomes.
The membrane are divided into three compartment
and they are intermembrane space, stroma, and
thylakoid space.
• Specialized metabolic compartment by a single membrane.
• It contain enzyme that transfers hydrogen substances to oxygen,
• Uses oxygen to break down fatty acid into smaller molecules that
can be transported to the mitochondria that are used to fuel cellular
respiration.
• Specialized peroxisome are called glyoxysomes that are found in
the fat stored tissues of plant seeds.
• They do not bud from the en endomembrane system, instead they
grow larger by incorporating protein made primarily in the cytosol
lipids made from ER.
• Cytoskeletons are network of fibers
extending throughout the cytoplasm.
• Play a major role in organizing the
structure and activities of the cell and
composed of three types of molecular
structure called microtubules,
microfilament, and intermediate filament.
Continue
• Important for animal cells because it lack
cell wall.
• More dynamic in animal cells than plant
cells.
• It quickly dismantled in one part of the cell
and reassembled in a new location.
• Regulate biochemical activities in the cell.
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A hollow tube with walls consist of 13
columns of tubulin molecules such as
compression-resisting grider.
Function as to maintain cell shape and cell
motility. Help chromosomes move during
cell division.
Responsible for cell movement.
•Grow from centrosomes, located near
the nucleus.
•Within the centrosomes there are pairs
of centrioles.
•Responsible for beating of flagella and
cilia.
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It has two intertwined strand of actin, each a polymer of actin subunits.
Main function to maintain cell shape such as tension bearing elements,
changes in cell shapes, muscle contraction, cytoplasmic streaming, cell
motility such as in pseudopodia, and cell division in cleavage furrow
formation.
• It is made up of fibrous protein super coiled into a thicker
cable.
• Main function is to maintain cell shape such as tension
bearing elements, anchorage of the nucleus and certain
organelles, and formation of nuclear lamina.
Plant cells
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Cell wall
Primary wall
Middle lamella
Secondary wall
CELL WALL
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Cell wall help distinguish between animal and plant cell
Help maintains shape of the cell and prevent excessive uptake of water
PRIMARY WALL
•Occurs in young plants
•Between the primary wall there is a middle lamella that glue and
adjacent cell together.
SECONDARY WALL
•When the plant grow older and mature it grows a secondary wall
between the plasma membrane and primary membrane.
•Strong and durable matrix that affords the cell protection and support.
Anima cells
Extracellular
Extracellular matrix (ECM) – help support the cell and giving it shape.
Collagen fiber- form strong fiber outside the cell
Prooteoglycan -glycoprotein
Fibranectin- attaches to the ECM glycoprotein.
Integrin – built into the plasma membrane that bind on their cytoplasmic
side to associated proteins attaching to the microfilament of the
cytoskeleton.
Intercellular junctions
Plant: plasmodesmata
• Cytosol passes through the plasmodesmata and connect chemical environment of
adjacent cell and help unify plant into one living continuum.
Animal: tight junction, desmosomes and gap junction
• Common in epithelial cells
• (Next slide for more information)
Cites
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http://dic.academic.ru/pictures/enwiki/77/Microscope_de_HOOKE.png
http://www.bio21.unimelb.edu.au/assets/image/1188543983-fei_tecnai_f30_trans_em.jpg
http://www.id.yamagata-u.ac.jp/CLRE/img/biochem_gif/u-cent-mini-top.gif
http://www.makehumans.com/images/wikimages/350px-Diagram_human_cell_nucleus.svg.png
http://www.vcharkarn.com/uploads/59/59679.png
http://wps.aw.com/wps/media/objects/1668/1708348/ebook/htm/campbell7e.htm?06.03
https://illnessesanimalsplants.wikispaces.com/file/view/smooth_&_rough_ER.jpg
http://wps.aw.com/wps/media/objects/1668/1708348/ebook/htm/campbell7e.htm?06.03
http://wps.aw.com/bc_campbell_biology_7/25/6655/1703824.cw/index.html
http://wps.aw.com/wps/media/objects/1668/1708348/ebook/htm/campbell7e.htm?06.04