cellular architecture
DESCRIPTION
Cellular Architecture. Or the typical/nontypical cell. Figure 4-1 Page 68. I.Limits to cell size. Surface to volume ratio 1. function of membrane 2. relationship of surface area to volume 3. consequences of growing too large. 1 mm. 2 mm. 2 mm. 1 mm. Figure 4-2 Page 68. - PowerPoint PPT PresentationTRANSCRIPT
Cellular Architecture
Or the typical/nontypical cell
Figure 4-1Page 68
I. Limits to cell size
A. Surface to volume ratio
1. function of membrane
2. relationship of surface area to volume
3. consequences of growing too large
Figure 4-2Page
68
2 mm
2 mm
1 mm
1 mm
I. Limits to cell size
B. Control issues1. Informational flow
2. Transcription
3. Diffusion
4. Translation
5. Cell gets too large, lag time in the control of activities
6. Analogy
II. Few Generalizations
• A. Procaryotic vs. eukaryotic
• B. Typical cell– 1. animal– 2. plant– 3. discuss the
similarities first
III. Organelles of synthesis
• A. Introduction– 1. Going to act as an assembly line– 2. Nucleus– 3. Endoplasmic reticulm– 4. ribosome– 5. Golgi apparatus
III. Organelles of synthesis
B. Nucleus-headquarters
1. chromatin
2. chromosomes
3. nucleolus
4. double membrane with pores
Nuclear Pores From Surface of Nuclear Membrane
Artist conception of nuclear pores
III. Organelles of synthesis
• C. Endoplasmic Reticulum• 1. definition• 2. nickname• 3. types of
– Rough– Smooth
Rough and smooth endoplasmic reticulum
Endoplasmic reticulum continuous with pores
III. Organelles of synthesis
• D. Ribosomes-protein synthesis• 1. found free in cytoplasm-endogenous use• 2. attached to E.R.-proteins for export• 3. responsible for translation of mRNA into protein
Ribosomes translate mRNA
III. Organelles of synthesis
• D. Golgi Body or Golgi Apparatus
• 1. nick name of bottling center• 2. modifies product• 3. concentrates product• 4. packages product into
vesicles• 5. exports via exocytosis
III. Organelles of synthesis
• E. Cell membrane with exocytosis
IV. Organelles of homeostasis
• A. Mitochondria• Nickname• Structure• Endosymbiosis• More active tissue• Both animal and plant
B. Chloroplasts
• Nickname• Structure• Endosymbiosis
Mitochondria and chloroplasts are tied tightly together
Figure 4-7(2)
Page 72
Vacuole
Cell wall
Plasma membrane
Granum Stroma
Chloroplast Rough and smooth endoplasmic reticulum (ER)
Nucleus
Nuclearenvelope
Nucleolus
Nuclearpores
Chromatin
Smooth ER
Rough ER
Ribosomes
C. Lysosome
• Nickname• Structure• Functions
D. Peroxisomes
• Similar in appearance to lysosomes• Contain enzymes important in lipid breakdown• Detoxification centers• Possess enzyme catalase important in the
breakdown of hydrogen peroxide
E. Cytoskeleton
Composed of microtubules and microfilaments
1. Microtubules
• “Skeleton” of the cell• Produce the structural
framework for cilia and flagella
1. microtubules
• Act as a railway along which organelles travel
• Microtubules may walk past one another
• Motor molecules may transport organelles from one area of the cytoplasm to another
2. microfilaments
• “muscles” of the cell• Same proteins that are found in our muscles
Microfilaments (cont)
• produce swaying of microvilli
• Movements of cytoplasmic streaming
Relationship of the cytoskeleton to the cell membrane and extracellular fibers
F. Cell wall of plant cells
• Primary cell wall• Secondary cell wall• Middle lamellae pectin• Importance of plasmodesmata
Plantcell walls
Plasmodesmata
Plasmodesmata
G. Centrioles
H. Central vacuole
I. Cilia and flagella
• Microtubules• 9 +2• Triplets in basal
body• Form from
centrioles?