Biology

Very helpful resource for regulation of cell cycle and function of CDK’s.

http://www.cellsalive.com/mitosis.htm

http://www.mun.ca/biology/desmid/brian/BIOL2060/BIOL2060-19/1925.jpg

Centrioles

Aster and Centrioles

http://www.pbs.org/wgbh/nova/baby/divi_flash.html

Receptor potential, a type of graded potential, is the transmembrane potential difference of a sensory receptor.

A receptor potential is often produced by sensory transduction. It is generally a depolarizing event resulting from inward current flow. The influx of current will often bring the membrane potential of the sensory receptor towards the threshold for triggering an action potential.

A receptor potential is a form of graded potential, as is a generator potential. It arises when the receptors of a stimulus are separate cells. An example of this is in a taste bud, where taste is converted into an electrical signal sent to the brain. When stimulated the taste bud triggers the release of neurotransmitter through exocytosis of synaptic vesicles from the presynaptic membrane. The neurotransmitter molecules diffuse across the synaptic cleft to the postsynaptic membrane.

SAMPLE AP QUESTIONS
>
>17.    Most cells that have become transformed into cancer cells
>have which of the following characteristics when compared to normal,
>healthy cells?
>    (A)    Shorter cell cycle
>    (B)    More carefully regulated rates of cell division
>    (C)    Lower rates of mitosis
>    (D)    Higher rates of protein translation
>    (E)    Identical DNA

shorter cell cycle is the answer.

the key to understanding this is the concept that the raison d’etre
of cancer cells is to make more cancer cells… that’s all… and
they do it as fast as they can. They don’t bother to stop and do the
other jobs that cells of that organ do. That’s what kills you. So
interphase is short because they are not doing their “normal jobs…
just going as fast as they can back into mitotic division… and
protein synthesis is probably less because they are not producing the
proteins necessary to do those “normal jobs”.

Please read 505-512 for HW.  You have also been given Chapter 22 & 23 Discussion Questions.

http://employees.csbsju.edu/hjakubowski/classes/ch331/signaltrans/neurotranskinase.gif

Homework for tonight - please read 465-473.

This reading concerns general features of animal anatomy.

Types of tissue, types of organ systems, regulation and feedback.

Schedule for the upcoming weeks will be published later today.

Echinderms are deuterostomes.  Humans are deuterostomes too.

http://www.mun.ca/biology/scarr/Protostomes_vs_Deuterostomes.html

Here are the details for the Evolution and Phylogeny Lab.  Responses MUST be typed on a separate piece of paper. (90 points) - Due Next Thursday - Feb 11th.

1.  Define the terms phylogeny, systematics, and cladistics.  These terms are defined in your textbook. (10 points).

2.  Describe why the field of phylogenetics is of interest to biologists. (10 points)

3.  Identify the criteria biologists use to organize and classify organisms?  Identify the limitations of using anatomical traits (think convergent evolution)? (10 points)

4.  Describe the principles of the Nutall precipitation technique.  Be sure to explain how this method provides information about the degree of relatedness between species.  Diagram a phylogenetic tree based on the data collected in this lab. (20 pts)

5.  Describe the principles of the Molecular Sequences and Primate Evolution activity.  In other words, how can a comparison of AA sequences provide information about evolutionary relationships? (20 points)

6.  Provide worksheets A and B.  Be sure they are completed AND With respect to Worksheet B: Cladistic Tree B - Identify the relationship between the years at the point of divergence (mya)  and the average number of changes in AA sequence, and describe how this relates to the concept of a molecular clock. (20 pts)

Please submit work that reflects your BEST effort.

Failure to so is a waste of your time and my time.