Download Chapter 3 The Basic Structure of a Cell

Cells – Part 2
1. Cell Membrane
Cell membrane
A. Lies immediately
against the cell wall in
plant cells
B. Maintains cell shape
C. Made of protein and
phospholipids
D. Selectively permeable
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Cell or Plasma Membrane
Cell membrane
1. Living layer
2. Selectively permeable
a. Controls the
movement of material
into and out of the
cell
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2. Cell Wall
2. Cell wall (Plant Cell)
A. Dead layer
B. Found in plants,fungi,
& bacteria
C. Freely permeable
D. Large empty spaces
between cellulose
fibers
E. Protects and supports
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3. Nucleus - The Control Organelle
Nucleus:
A. Controls the normal
activities of the cell
B. Contains the DNA
in chromosomes
C. Bounded by a
nuclear envelope
(membrane) with
pores
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The Control Organelle
Nucleus:
Chromosomes: the genetic
material of the cell
i. In non-dividing
cells they appear as
thin, threadlike
strands called
Chromatin
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4. Nuclear Envelope
Nucleus
Nuclear envelope: outer
boundary of nucleus,
consists of double membrane
containing pores
i. Controls what
enters and leaves the
nucleus
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5. Nucleolus
Inside nucleus
A. Cell may have 1
to 3 nucleoli
B. Disappears
when cell divides
C. Makes
ribosomes that
make proteins
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6. Cytoplasm
cytoplasm
Jelly-like substance
enclosed by cell
membrane
A. Provides a medium for
chemical reactions to
take place
B. Contains organelles to
carry out specific jobs
C. Found in ALL cells
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7. Ribosomes
A. Tiny particles floating
freely in cytoplasm or attached
to ER
B. NOT membrane-bound
C. Made of protein and RNA
molecules
D. Where protein synthesis
occurs
E. Bacteria cell = 1000’s
F. Human liver cell = millions
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Endoplasmic Reticulum - ER
1. Folded system containing a network of
hollow membrane tubules
2. Provide a large surface area for chemical
reactions
3. Purpose: serves as a transport system for
materials inside the cell
4. Two types: Smooth E.R. & Rough E.R.
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8. Smooth Endoplasmic Reticulum
1. Smooth ER lacks
ribosomes on its surface
2. Is attached to the ends
of rough ER
3. Makes proteins USED
in the cell, also
involved in
carbohydrate and lipid
synthesis
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9. Rough Endoplasmic Reticulum
(Rough ER)
1. Has ribosomes on
its surface
2. Makes membrane
proteins and
proteins for
EXPORT out of cell
3. Continuous with
the nuclear
envelope
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10. Golgi Bodies
1. Stacks of flattened
sacs
2. Have a shipping side
(trans face) and
receiving side (cis
face)
3. Receive proteins made
by ER
4. Transport vesicles
with modified proteins
pinch off the ends
CIS
TRANS
Transport
vesicle
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11. Lysosomes
1. Contain digestive
enzymes
2. Break down food,
bacteria, and worn out
cell parts for cells
3. Programmed for cell
death (AUTOLYSIS)
4. Lyse (break open) &
release enzymes to
break down & recycle
cell parts
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