BIOH111 [SESSION 3]
Tutorial- CELL COMMUNICATION/CELL DIVISION
Learning Outcomes:


Describe and understand cell signalling, its components and significance.
Describe and understand cell division (mitosis & meiosis), with particular
focus on mitosis.
Aims:


To view and analyse animation on the cellular signaling
To view and analyse animation on cell division
© Endeavour College of Natural Health
Last updated on 18-Jul-16
80bce850e409470d9f17274aef144396
Page 1 of 5
Activity 1:
A. Watch the following video animation (2-3 minutes) related to cell signaling,
and pay particular attention to the ‘input/processing/output’ cascade of events:
https://www.youtube.com/watch?v=FtVb7r8aHco
B. Write a summary paragraph outlining the main points of events of cell
signaling by answering the following questions:
1. What do you think is the first step of the signaling cascade?
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
2. Why is this step important?
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
3. What happens after the initial step and why is this important in the events that
happen inside the cells next?
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
© Endeavour College of Natural Health
Last updated on 18-Jul-16
80bce850e409470d9f17274aef144396
Page 2 of 5
4. Describe the intracellular events that happen once the G-protein is activated
(you can use the lecture slides as a guide also).
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
5. What is the outcome of the signaling cascade? Why does it need to happen?
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
___________________________________________________________________
Activity 2:
A. Watch the following cell divisions animation:

https://www.spongelab.com/browse/index.cfm (search “thread of life”, then
watch the video about mitosis) 1 minute

https://www.khanacademy.org/science/biology/cellular-molecularbiology/mitosis/v/mitosis

(mitosis) 12 minutes
https://www.spongelab.com/browse/index.cfm (search “crash course biolo”,
then watch the video about meiosis) 6 minutes
B. Outline all the stages that somatic cells go through when they divide (i.e.
mitosis).
________________________________________________________________
________________________________________________________________
________________________________________________________________
________________________________________________________________
© Endeavour College of Natural Health
Last updated on 18-Jul-16
80bce850e409470d9f17274aef144396
Page 3 of 5
________________________________________________________________
________________________________________________________________
________________________________________________________________
________________________________________________________________
________________________________________________________________
________________________________________________________________
________________________________________________________________
________________________________________________________________
________________________________________________________________
________________________________________________________________
C. Answer the following questions:
1. In which mitotic stage (phase) does DNA replication occur and how?
________________________________________________________________
________________________________________________________________
________________________________________________________________
________________________________________________________________
________________________________________________________________
2. What happens during late prophase of mitosis?
________________________________________________________________
________________________________________________________________
________________________________________________________________
________________________________________________________________
________________________________________________________________
________________________________________________________________
________________________________________________________________
3. What happens during Anaphase?
________________________________________________________________
________________________________________________________________
________________________________________________________________
________________________________________________________________
________________________________________________________________
© Endeavour College of Natural Health
Last updated on 18-Jul-16
80bce850e409470d9f17274aef144396
Page 4 of 5
________________________________________________________________
________________________________________________________________
4. If (2n) is the total number of chromosomes of the mother cell just before
entering mitosis, what will be the total number of chromosomes for the 2
daughter cells?
________________________________________________________________
________________________________________________________________
________________________________________________________________
________________________________________________________________
________________________________________________________________
________________________________________________________________
________________________________________________________________
5. Which cell division mechanism is similar to mitosis: meiosis I? or meiosis II ?
________________________________________________________________
________________________________________________________________
________________________________________________________________
________________________________________________________________
________________________________________________________________
________________________________________________________________
________________________________________________________________
Go back to your cell concept map and incorporate into it cellular signalling
and where cell division starts.
Composed by Dr Akram Kabbara
© Endeavour College of Natural Health
Last updated on 18-Jul-16
80bce850e409470d9f17274aef144396
Page 5 of 5