Thursday, 25 January 2007




Q2)b. What are the advantages and disadvantages of animal cells only having a cell membrane (Compared to a cell wall found in plants)?


Function of the Cell wall:
The function of the cell wall is to allow the circulation and distribution of water,minerals and other small nutrient molecules into and out of the cell. It also acts as a physical barrier to substances like pathogens, and the strong cell wall prevents expansion when water enters the cell. Most importantly, it provides support and mechanical strength to allow plants to get tall, holding out thin leaves to obtain light, and it also gives the plant cell a regular shape.

Disadvantage of not having a cell wall in animal cells:

The disadvantage of the animal cell not having a cell wall is that the cell membrane is not strong enough to be able to protect the interior from any physical movement that may damage the cell, and also to provide support for the cell like the plant cell. Also, the cell wall of the plant cell prevents it from bursting, so it is sturdier in comparison to the animal cell.

Advantage of not having cell wall in animal cells:
However, as much as cell walls has their advantage, they can actually make a cell rigid, and it is not needed in an animal system. That is because with a regular shaped cell, these cells would not be able to pass and squeeze through our blood vessels or other small places that our animal cells are now able to squeeze through. Having these rigid cell walls may also cause a blood clot, so the cell wall has its disadvantages too.

So there are reasons why God created animals without cell walls afterall :D
QUESTION ONE
Come up with an analogy of an animal cell.

You may choose the following methods to present your analogy.
1. A picture with explanation of the different parts
2. Description of the analogy.

In your analogy, you must include the following eight organellesNucleus, Nucleolus, Ribosomes, Rough endoplasmic reticulum, Golgi Apparatus, Lysosomes, Plasma membrane and Mitochondria


Spaghetti analogy of animal cell

ate of nice smelling spaghetti (proteins) comes out fresh from the kitchen! The chef (ribosomes) looks at it with a satisfying smile, another piece of successful work! His work everyday is to cook in this kitchen, producing plates of spaghetti for the customers (lysosomes), who always seem to be able to gobble up the plate of spaghetti within seconds. To be put in other words, they can actually be described as chomping machines that can make these spaghetti (proteins) disappear!

Thanks to the efficient waiters (Rough Endoplasmic Reticulum) who delivers the orders around the restaurant, the flow of customers is steady, and the restaurant gets very popular due to the delicious spaghetti and also the working pace. Of course, the success of this restaurant is mainly due to the amazing recipe (nucleus), and it seems like the entire business of the restaurant revolves around it, in other words, we can say this recipe is the center and the most important part of the restaurant, it just feels as if it controls the restaurant.

The man behind this amazing recipe (nucleus) is our boss and employer (nucleolus), he is the man who trains us, the chefs (ribosomes), to learn about the art of cooking. In other words, he is like our producer that can make us perfect for this important job!
Besides, he is also the person who invented the method of baking the spaghetti for a short while before serving! Therefore, the oven (mitochondria) seems to power up our spaghetti and bring it on to a higher level of delicious taste! Yum!

Nowadays, we are receiving so much orders such that we even do delivery jobs! We have recently hired some young men to do delivery jobs. These Delivery boys (Golgi apparatus) work well, and they wait at the counter for the order, packs the spaghetti up and sets off, leaving the restaurant door (Plasma membrane) for the delivery job.

Having such an efficient restaurant, don’t you think its time to try our secret recipe spaghetti too? ;]




Nucleus--Recipe
Necleolus--Boss/Employer
Mitochondria--Oven
Golgi Apparatus--Delivery man
Rough ER--Waiter
Ribosomes--Chef
Lysosomes--customers
Proteins--Pizza
Plasma membrane--restaurant door

Thursday, 11 January 2007


This is my first biology blog post!

i've found some interesting facts on VIRUSES
they'll be in point for for easy reading

and they're really interesting! ;)


- Firstly, a virus is a microscopic particle that can infect the cells of a biological organism.

- The plural form is virus, the singular form is virion

- Viruses replicate themselves by infecting a host cell

- Therefore, they cannot reproduce on their own like how cells do

- The word "virus" is a latin word for Poison!

- viruses has a protective protein coat, capsid, that contains genetic materials

- the genetic material and protein in a virus distinguishes them from other virus like particles like prions and viroids

- They infect a wide variety of organisms, animals, fungi, plants and bacteria!

- A virus that infects bacteria is known as a bacteriophage, often shortened to phage.

- The study of viruses is known as virology, and those who study viruses are known as virologists.

- Virologist consider them as non-living organisms as they lack the means for self-reproduction outside a host cell

- However, there still is not a definitive answer, becuase it has both the characteristics of both living and non living particles

- Viruses are NOT made up of cells

- Bacteria can be attacked by viruses!

- There are four types of viruses:
1) Helical viruses
2) Icosahedral viruses
3) Enveloped viruses
4) Complex viruses


- Talking about the size of a virus, a medium sized virion next to flea, is like putting a human next to a mountain twice the size of mount Everest!

- Virus contain either DNA (Deoxyribonucleic acid) or RNA (Ribonucleic acid). they won't contain both.

- Viruses like Ebola and small pox causes epidemics!

- It is difficult to eliminate a virus without killing the host cell!


here's some types of viruses:
1) warts
2) Yellow fever
3) AIDS
4) influenza
5) Hepatitis
6) Chicken pox

these are more common forms of viruses
and we need a good inmmune system to cure these viruses.


















Here are some pictures of viruses i found:















the influenza virus.





Monday, 8 January 2007

Hello testing post! (: