Key Points: 1. Structure (and importance) of cell membrane 2.
Structure (and function) of organelles 3. Interconnections between
cells to maintain structural stability in body tissues.
Cell membrane (plasma membrane ) The ________ ________ model
describes the structure of the plasma membrane. In this model the
membrane is seen as a bilayer of ______________ in which protein
molecules are embedded. (fill the blanks) Name the functions of
cell membrane proteins 1. _____________ 2. _____________ 3.
_____________ 4. _____________ 5. _____________
Slide 5
Cell membrane (plasma membrane ) The fluid mosaic model
describes the structure of the plasma membrane. In this model the
membrane is seen as a bilayer of phospholipids in which protein
molecules are embedded. Functions of proteins 1.Cell adhesion
molecule 2.Carriers 3.Pumps 4.Ion channels 5.Receptors
6.Enzymes
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Non-membranous Organelles Name the non-membranous organelles.
1. 2. 3. 4.
Cytoskeleton Q. Name the 4 major components: 1.________________
2.________________ 3.________________ 4.________________ Q. What is
its function: ____________
Slide 9
Cytoskeleton Answer: The 4 major components are,
1.Microfilaments (mostly actin) 2.Intermediate filaments 3.Thick
filaments (composed of myosin subunits) 4.Microtubules (composed of
tubulin subunits) Function: support & movement of cellular
structures & materials
Slide 10
Slide 11
2 centrioles direct formation of mitotic spindle In 9+0
array
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The centrosome, also called the "microtubule organizing
center", is an area in the cell where microtubles are produced.
Within an animal cell centrosome there is a pair of small
organelles, the centrioles, each made up of a ring of nine groups
of microtubules. There are three fused microtubules in each group.
The two centrioles are arranged such that one is perpendicular to
the other. During animal cell division, the centrosome divides and
the centrioles replicate (make new copies). The result is two
centrosomes, each with its own pair of centrioles. The two
centrosomes move to opposite ends of the nucleus, and from each
centrosome, microtubules grow into a "spindle" which is responsible
for separating replicated chromosomes into the two daughter
cells.
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Cilia In 9+2 array These are thread-like projections of certain
cells that beat in a regular fashion to create currents that sweep
materials along; Q. Name sites where cilia can be found.
1._____________ 2._____________ Answer: 1.Respiratory epithelium
2.Fallopian tube
Slide 14
Flagella These may extend to the rear of a cell and push it
forward by snakelike wriggling, or stick out in front and draw it
along. Q. Where can flagella be found in humans? __________________
Answer: Sperm Each sperm cell is propelled by a trailing flagellum
that accelerates the little torpedo forward in its quest to
fertilize an egg.
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Ribosomes Q. Ribosomes are made up of 60% _______ & 40%
_______. They are active in _______ synthesis. There are 2 types of
ribosomes 1.__________ 2.__________ Answers: 60% RNA + 40% Protein
Active in protein synthesis There are Fixed (on RER)and free
ribosomes
Slide 16
Membranous Organelles
Slide 17
Nucleus
Slide 18
The nucleus is the control center of the cell. It is the
largest organelle in the cell and it contains the DNA of the cell.
The DNA of all cells is made up of ______________. DNA +
_________proteins = Nucleosome ____________ + Linker DNA =
Chromatin Answer: The DNA of all cells is made up of chromosomes.
DNA + Histone proteins = Nucleosome Nucleosome + Linker DNA =
Chromatin
Slide 19
Inside the nucleus is another organelle called the nucleolus.
The nucleolus is responsible for making ribosomes. The
fenestrations on the surface of the nucleus are the nuclear pores.
These are where ribosomes, and other materials move in and out of
the cell.
Slide 20
Mitochondria
Slide 21
Mitochondria are sometimes described as "cellular power plants"
because they generate most of the cell's supply of adenosine
triphosphate (ATP), used as a source of chemical energy Every type
of cell has a different amount of mitochondria.. There are more
mitochondria in cells that have to perform lots of work, for
example- your leg muscle cells, heart muscle cells etc. Q. The
mitochondrion has its own independent genome inherited from which
gametocyte? Answer: Ovum
Fill in the blanks ER is a network of membranes throughout the
cytoplasm of the cell. There are two types of ER. When
______________are attached it is called rough ER (RER)and smooth ER
(SER) when there are no ______________ attached. The rough
endoplasmic reticulum is where most ________________ occurs in the
cell. The function of the smooth endoplasmic reticulum is to
synthesize __________in the cell. The smooth ER is also helps in
the ___________of harmful substances in the cell.
Slide 24
Answer ER is a network of membranes throughout the cytoplasm of
the cell. There are two types of ER. When ribosomes are attached it
is called rough ER (RER)and smooth ER (SER) when there are no
ribosomes attached. The rough endoplasmic reticulum is where most
protein synthesis occurs in the cell. The function of the smooth
endoplasmic reticulum is to synthesize lipids in the cell. The
smooth ER is also helps in the detoxification of harmful substances
in the cell.
Slide 25
Golgi Apparatus vesicles come from ? Packaging and shipping of
proteins Packaging and shipping of proteins Cell membrane
renewal
Slide 26
Lysosomes Function as the cell's recycling compartment.
Lysosomes receive cellular and endocytosed proteins and lipids that
need digesting. The metabolites that result are transported either
by vesicles or directly across the membrane.
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Q. Name A, B, C & D
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Answer:
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Intercellular Attachments channel proteins interlock and form
pores Q. Where are they abundantly seen? Answer: abundant in
cardiac and smooth muscle 1) Gap Junctions
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2) Tight Junctions Interlocking membrane proteins Q. Where are
they abundantly seen? Answer: Found near surface of cells lining
the digestive tract.
Slide 31
3) Desmosomes Proteoglycan layer reinforced by transmembrane
proteins (cell adhesion molecules or CAMs) Belt, button and
hemidesmosomes Q. Where are they abundantly seen? Answer: Found in
superficial layers of skin