lecture 19 homework review today apoptosis and cancer n.
Skip this Video
Loading SlideShow in 5 Seconds..
Lecture 19 Homework Review Today: Apoptosis and Cancer PowerPoint Presentation
Download Presentation
Lecture 19 Homework Review Today: Apoptosis and Cancer

Loading in 2 Seconds...

play fullscreen
1 / 15

Lecture 19 Homework Review Today: Apoptosis and Cancer - PowerPoint PPT Presentation

  • Uploaded on

Lecture 19 Homework Review Today: Apoptosis and Cancer. Monday April 23rd- Cell-Cell Interactions/Tissues Thursday April 26 th -Early Development and Stem Cells Monday April 30 th - Review Final Exam May 9 th 12-1:30pm in this classroom

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
Download Presentation

PowerPoint Slideshow about 'Lecture 19 Homework Review Today: Apoptosis and Cancer' - mindy

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
lecture 19 homework review today apoptosis and cancer

Lecture 19Homework ReviewToday: Apoptosis and Cancer

Monday April 23rd- Cell-Cell Interactions/Tissues

Thursday April 26th -Early Development and Stem Cells

Monday April 30th- Review

Final Exam May 9th 12-1:30pm in this classroom

For Exam III- You are not responsible for any material in assigned chapters relating to Plants!

Homework Lecture 15 and 16
  • In cells, the concentration of actin monomer is higher than required for purified actin monomers to polymerize in vitro. Thymosin is a protein that can bind actin monomers and sequesters them. If you add a drug that inhibits the ability of thymosin to bind actin monomers, what would be the effect on actin polymerization? INCREASE POLYMERIZATION

Actin Filament



2. Which of the following changes occurs when a skeletal muscle fiber contracts?A) The A bands ShortenB) The I Bands ShrinkC) The Z lines slide farther apartD) The Thin Filaments ContractE) The Thick Filaments Contract

Dark Band- A band

Light Band- I band

3.Consider an Individual Microtubule:

What must happen at the end of the microtubule in order for it to stop shrinking and start growing?

-Binding of GTP Tubulin Heterodimers to form a GTP Cap

How would a change in the tubulin concentration affect this switch?

Increase in Tubulin Heterodimers- Promote Rescue

Decrease in Tubulin Heterodimers- Continue Shrinking

What would happen if only GDP, but no GTP, were present in the solution?

MT Depolymerization would occur

What would happen if the solution contained a nonhydrolyzable form of GTP?

MT Continued Polymerization until no available Heterodimers left

4. Nucleation of Actin Monomers or Microtubule Heterodimers is the Slow Step in the formation of Actin and Microtubule Filaments in vitro. How do cells bypass the slow step in vivo in the formation of A) MT filaments – MTOCs and B) Actin Filaments? ARP COMPLEX
5) What is the role of Nexin in the Axoneme of Cilia and Flagella. What would happen if it wasn’t present? Couldn’t bend-filaments would slide


6)The Hydrolysis of GTP to GDP carried out by Tubulin Molecules:

A) Provides Energy Needed for Tubulin to Polymerize

B) Occurs Because the Pool of Free GDP Has Run Out

C) Tips the Balance in Favor of Assembly

D) Allows the Behavior of Microtubules called Dynamic Instability


Homework 17 and 18. Due Monday- we will go over these answers.

True or False and Why?

  • Cells do not pass from G1 to M phase of the cell cycle unless there are sufficient nutrients to complete the whole cell cycle.

No cell goes from G1 directly to M

Homework 17 and 18. Due Monday- we will go over these answers.

True or False and Why?

2) Rb is a transcription factor that must be phosphorylated in order for expression of G1/S and S phase Cyclins. FALSE- not functioning as a transcription factor in this case- but as inhibitor of transcription factor

True or False and Why?

3) Once a Cyclin binds to a CDK, the kinase is active and can immediately begin phosphorylating targets.


4) Separation of sister chromatids requires kinetochore MT assembly and cytoplasmic dynein activity. FALSE

Anaphase A Movement

Plus End of Kinetochore Microtubules Dissassembles

Minus End Directed Motor

(Dynein) Proteins Pull

Toward Spindle Pole

Pac Man Mechanism

MT Depolymerize

Dynein Walks

Toward Minus End


5) When a cell that is in the process of replicating DNA is fused with a cell in G1:
  • The replication of DNA occurring in the original S nucleus is terminated

B) DNA synthesis begins immediately in the original G1 nucleus

C) The two Nuclei Fuse and Further Division is Arrested

D) The Chromosomes of the Original G1 Nucleus condense in preparation for mitosis

E) The original G1 cell will divide immediately


6.) Sister chromatids:

A) Are created when DNA is replicated

B) Are attached at the centromere prior to Division

C) Are separated during anaphase

D) Have matching copies of the chromosome’s DNA

E) all of the above

7.) In some cases, Mitosis occurs without cytokinesis occurring. This will result in:

A) Cells with more than one nucleus

B) Cells that are unusually small

C) Cells lacking nuclei

D) Destruction of chromosomes

E) Cell cycles lacking an S phase