Download 08. Cell Organelle II

☰





Search
Explore
Log in
Create new account
Upload
×
D’YOUVILLE COLLEGE
BIOLOGY 102 - INTRODUCTORY BIOLOGY II
LECTURE # 8
CELL STRUCTURE II
4.
Energy-producing Organelles:
• mitochondria (fig. 6 – 17 & ppt. 1): frequently sausage-shaped; important
generator of energy (ATP) for the cell (aerobic respiration)
- membranes: organized into outer and inner membranes; inner is folded into
cristae
- compartments: intermembrane space + internal matrix
• chloroplasts (fig. 6 – 18 & ppt. 2): specialized plastid containing
chlorophyll
for photosynthesis
- internal organization: elliptical shape with internal stroma; pigment
photosystems are highly ordered and arrayed on thylakoids (membranes with
granal &
intergranal regions)
5.
Cytoskeleton: fibrous substances acting to maintain integrity and shape of
cell
structure (intermediate filaments); also instrumental in cell motility (fig.
6 – 20, table 6
– 1 & ppts. 3 & 4)
• microtubules: composed of protein, tubulin; capable of lengthening or
shortening to direct movements of attached structures (chromosomes); provide
tracks for
movement through cytosol (collaborate with motor proteins) (fig. 6 – 21 &
ppt. 5)
- microtubular organizing centers: animal cells grow microtubules from
centrosomes, some with centrioles (microtubular structures with 9 triplet
arrangement –
fig. 6 – 22 & ppt. 6)); in plants this function is performed by an
unidentified organelle
Biology 102, lec 8 - Spring ‘12
page 2
- cilia & flagella (fig. 6 –23, 6 – 24 & ppts. 7 & 8): involve microtubular
cores
with a “9 + 2” arrangement (derived from basal bodies); involved in
extracellular motility
(collaborate with motor proteins) (fig. 6 – 25 & ppts. 9 & 10); flagellar
motion –
undulating action generates motion parallel to flagellum axis; ciliary motion
– oar-like
action generation motion perpendicular to cilium axis (fig. 6 – 23 & ppt. 7)
- spindle apparatus of cell division: microtubules direct movements of
chromosomes in cell division
• microfilaments (fig. 6 – 26, 6 – 27 & ppt. 11): threadlike strands composed
of
actin confer gel-like quality to external cytoplasm (cortical cytoplasm),
helping stabilize
shape; interaction with myosin at one end of cell extrudes liquid central
cytoplasm at
other end into pseudopodium
- in skeletal muscle, thicker myosin microfilaments overlap with actin to
cause
contractile movements
6.
Cell Periphery:
• cell walls (fig. 6 – 28 & ppt. 12): non-living outer layers (plants, fungi,
bacteria)
- plant cell wall – cellulose impregnated with various other substances;
fungi
and some bacteria feature walls of chitin (polysaccharide)
• extracellular matrix: mixture of proteins, polysaccharides and
proteincarbohydrate complexes; facilitate communication between extracellular
milieu & cell
interior (animal cells – fig. 6 – 30 & ppt. 13)
• cell-to-cell junctions: cytoplasmic bridges span walls of adjacent plant
cells
(plasmodesmata) (fig. 6 – 31 & ppt. 12)
Biology 102, lec 8 - Spring ‘12
page 3
- animal cell junctions serve to seal intercellular spaces (tight junctions),
to
hold cells together (desmosomes), or to facilitate intercellular transmission
of materials
(gap junctions) (fig. 6 – 32 & ppt. 14)
Download
1. Science
2. Biology
3. Cell Biology
08. Cell Organelle II.doc
Chloroplasts and photosynthesis
11. Chemreact-enz.doc
A2 4.3.1 Photosynthesis
Biol 178 Lecture 7
Chloroplasts
View Revision Note
Energy in cells - Skinners` School Science
PHOTOSYNTHESIS is a physiological process by
Plastids Lect. 7
61 Chloroplasts and Mitoch
Bones - Our eclass community
Chapter 15 Summary (Photosynthesis)
studylib © 2017
DMCA Report