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Revision as of 18:54, 12 May 2009 by S8600021 (talk | contribs)

You have now created your individual project page.

--Mark Hill 18:54, 12 May 2009 (EST) You have been doing your homework items, but your individual project (due week 10) need some significant work.

--Mark Hill 09:15, 16 April 2009 (EST) You have not yet selected your individual project protein/method topic and still missing some homework items. 2009_Student#Individual_Projects Individual Projects

--Mark Hill 09:17, 19 March 2009 (EST) Thanks for the feedback! Just a minor correction, the inner nuclear cytoskeleton consists of the intermediate filament protein lamin not laminas.

--Mark Hill 08:24, 8 April 2009 (EST)All your homework is now up to date. Though "What I didn't understand is the significance of the overall process of exocytosis." is not really a concept. Lets see if it is still a problem for you after the ECM lecture.


1.Lecture 4 - Nucleus - What did you find interesting and did not know about the nucleus?

What I learnt in today's cell biology lecture on the nucleus is that the nucleus consists of both an internal and external cytoskeleton which help support and give the nuclear membrane its shape. The outer nuclear cytoskeleton is more random and less dense than the inner nuclear cytoskeleton, and involved in the translocation of the nucleus, while the the inner nuclear cytoskeleton is uniquely made up of intermediate filament protein lamins (type A's ,including A and C, and type B's, including B1 and B2), and is involved in the disassembly of the nuclear envelop whenever mitosis or meiosis occurs.

2.Lecture 5 - Exocytosis - What concept about exocytosis did you find difficult to understand?

What I didn't understand is the significance of the overall process of exocytosis.

3.Lecture 7 - Mitochondria - What types of cellular processes require lots of energy from the mitochondria?

Energy is required when electrical conduction occurs in unmyelinated axons for either muscle contraction or neuronal synapses.

Sperm tail motility in spermatozoon and flagella motility in bacteria require copious amounts of energy to power up their mini motors.

Fibroblasts which play a continuous role in the growth and repair of stroma (extracellular matrix and collagen) also require infinite amounts of energy produced by near by mitochondria.

One last mention where mitochondrial energy is needed is at the plasma membrane, for import and export of substances, through various processes including that of active transport and reverse osmosis.

4.Lecture 8 - Adhesion - What do the different "CAM" acronyms stand for?

Cell Adhesion Molecules (CAMs) family:

N-CAM = Neural Cell Adhesion Molecule

Ng-CAM = Neuron-glia Cell Adhesion Molecule

L-CAM = Liver Cell Adhesion Molecule

I-CAM = Intercellular Adhesion Molecule

5.Lecture 10 - What is the name of the epidermal layer between the basal and granulosa layer and how does it relate to intermediate filaments?

Stratum Spinosum. The cells in this epidermal layer exhibit numerous cytoplasmic processes(intermediate filaments) that are attached to processes of adjacent cells by desmosomes.

6.Lab 6 - "If you've seen differences in the distribution of phenotypes in Tm4 over-expressing B35 cells versus control B35 cells, describe these differences. Formulate a hypothesis with regards to what changes on the molecular level may have occurred due to the over-expression of Tm4 that lead to morphological changes that you have observed"

Genotype A corresponded to the tm4 over-expressing B35, while Genotype B corresponded to the wildtype control B35 cells. Between these two genotypes differences in their distribution of phenotypes was observed through total cell counts. In the control B35 cells, the majority of cells were of stumped or prolonged phenotypes, with all other phenotypes,(besides fan phenotype with nearly no cells), receiving an equal distribution of remaining cells. However, changes were seen when observing the phenotypes of the Tm4 over-expressing B35 cells, with the majority of cells falling into prolonged and stringed phenotype groups, followed by the stumped phenotype. The remaining phenotype cell counts were very small to none. It can therefore be seen through the results that Tm4 induces stringed phenotypes, and thus the production of lamella and processes.


The over-expression of Tropomyosin 4 in neuronal cells results in morphological phenotype changes to the Intermediate Filament, Microtubule and Microfilament components of the cellular cytoskeleton, and hence increasing the number neuronal processes found on the neurons.

7.Lecture 14 - Confocal Microscopy - What are the 2 main forms of generating confocal microscopy?

The two methods which bring about the use of confocal microscopy are laser scanning and spinning disc techniques.

8.Lecture 15 - What does the "S" stand for in the S-phase of the cell cycle?

Synthesis phase, where DNA duplication or synthesis occurs within the growing cell.