Greetings to Class 2E1!

This blog is created to help YOU in learning Biology in fun and interesting ways. New topics would be posted every month so do look out for them. Each topic would be introduced in different posts. If you have any queries, feel free to leave a comment!

Regards,
Ms Lonuco



Sunday, October 5, 2008

Nutrition in Animals

The first topic we shall explore is on
"
Nutrition in Animals".

Have you wondered what happens to the food that you eat every meal?





Scenario :

June woke up with a rumbling stomach. Without washing up, she hurried to the kitchen and rummaged through her refrigerator.

And there it lies... a Caesar Chicken Sandwich.....

She gobbled it down till the very last bite.



She began the day as a happy woman and smiled happily.

Then she pondered....

"Hmmm.. I wonder what happened to my sandwich.
Where did it all go?"

Let us help June to uncover the Mystery of the Missing Sandwich!!

Explore the following posts and unravel... the MYSTERY!

Warning: You have only 50 min
utes to help June explore all four sections.

Begin!


Mouth

Let us begin by looking at the mouth. Click here and watch the section on "oral cavity".

Activity I

The video mentioned that saliva is important in keeping food moist and aiding in chemical digestion of food. As a group, identify the name of the enzyme found in saliva and its specific action. Click here for more information.

Activity II

Play the video “Plain biscuits turn sweet”. Explain the phenomenon in "Check Your Understanding".



Check Your Understanding here!


Oesophagus

Play the video clip to explore the oesophagus and find out its role in facilitating digestion.

Activity I - Video Recording

In this activity, put your hands into action. In box A given, you will find transparent stockings and ping pong balls. As a group, do a web cam recording to simulate the movement of bolus down the oesophagus as seen in the video. Keep your recording to less than 1 minute.

Navigation guide to recording and uploading of video:

1. Double left-click on the web cam icon found on the Desktop.
2. Start recording.
3. Save the file using the format "Recording_(Group Number).mpg" onto the Desktop.
4. Cut and paste the file into the folder "Video-making Class 2E1" on the Desktop.

Check Your Understanding here!


Stomach

The stomach is located between the oesophagus and the small intestine. It is made up of several layers of smooth muscle and connective tissues.



The stomach has several functions. Click here and identify 3 functions of the stomach.


Environment



The stomach produces and secretes hydrochloric acid. Therefore, it has a highly acidic environment (pH~ 1 to 2). How does the stomach protect itself from the acidic environment and keep from digesting itself? Brainstorm on this in your group and post your comments.



Does the picture below look familiar?



Yes, it is a mixer. The stomach behaves just like the mixer which churns the food into a pulp called chyme.



Enzyme



Enzymes are also secreted into the stomach to break down the food into smaller substances.

Watch this video to find out about enzymes in our stomach.

After the food is digested in the stomach, it moves into the small intestine.


Check Your Understanding
here!


Saturday, October 4, 2008

Small Intestine

Chyme from the stomach enters the small intestine where it is the site of final digestion. Enzymes found in the small intestine will aid to complete the digestion of food.

Carbohydrates are digested into simple sugars by carbohydrases.

Proteins are digested into amino acids by proteases.

Fats are digested into fatty acids and glycerol by lipases. Emulsification of fats by bile helps in digestion of fats.

What are the other functions of the small intestine?

View this animation to find out more. Refer to points 3 (Duodenum) and 4 (Ileum).

Check Your Understanding here!

__________________________________________________________________

Congratulations! We have completed exploring the process of digestion.

Group Assignment


Remember the Caesar Chicken Sandwich June had for breakfast. Let us check the ingredients:


In your groups, prepare a write-up of no more than 250 words on how each of the ingredients would be digested in June's body. You may use the Internet like google to obtain additional information. Do remember to include your references. Points to be included:

-
Identify the component which contains carbohydrates, fats, fibres or proteins.

- What happened to each component of the sandwich?

To be submitted in word document by the next lesson to my email:
ms_lonuco@letters.com

Individual Assignment


Individually, write a short reflection to summarise the difficulties encountered while working in your group and additional knowledge gained from the write-up. The reflection should be less than 100 words.

To be submitted in word document by the next lesson to my email:
ms_lonuco@letters.com