Tutor Niedino: Pri Science Questions and Concepts

[atutor2001]

Joy:

May I ask, when we write Plant has a fixed cell wall, awarded full marks.

What about Plant has a rigid cell wal?Is it deduct half mark?

Thanks


Rgds
Joy

In my opinion \"rigid\" should be the correct word - not fixed. I will give zero mark for \"fixed\" as the meaning is totally different from rigid. But the wall cannot be spelled as \"wal\" - otherwise no mark as wall is the other key word.

Try googling for \"rigid cell wall\" and \"fixed cell wall\" you will find how the word \"fixed\" is used in relation to cell wall.

[Tang]

Joy:

May I ask, when we write Plant has a fixed cell wall, awarded full marks.

What about Plant has a rigid cell wal?Is it deduct half mark?

Thanks


Rgds
Joy

Hi,

Why is there a need to describe the cell wall?

I will just answer as follows:

Plants have cell walls.

or

Plants have cell walls that give them regular shape.

[Leanne]

I got a reply from her teacher:


In Science, the specific meanings of the words is important.
Different adjectives means different things in Science.
According to Longman, the word rigid means \"stiff, not moving or bending\" - a movement.
However, we are looking for the inability of the cell to change shape - because it has been fixed by the cell wall.

atutor2001:

Joy:

May I ask, when we write Plant has a fixed cell wall, awarded full marks.
What about Plant has a rigid cell wal?Is it deduct half mark?

Thanks


Rgds
Joy

In my opinion \"rigid\" should be the correct word - not fixed. I will give zero mark for \"fixed\" as the meaning is totally different from rigid. But the wall cannot be spelled as \"wal\" - otherwise no mark as wall is the other key word.

Try googling for \"rigid cell wall\" and \"fixed cell wall\" you will find how the word \"fixed\" is used in relation to cell wall.

[Leanne]

delted

]

[Full.010894Cream]

Tang:

Hi,


Why is there a need to describe the cell wall?

I will just answer as follows:

Plants have cell walls.

or

Plants have cell walls that give them regular shape.

Thinking the same thing here...is it necessary to give additional info/description? What is the context of the qn?

[Leanne]

state the function of the cell wall.

Full.Cream:

Tang:

Hi,

Why is there a need to describe the cell wall?

I will just answer as follows:

Plants have cell walls.

or

Plants have cell walls that give them regular shape.

Thinking the same thing here...is it necessary to give additional info/description? What is the context of the qn?

[Tang]

Leanne:

state the function of the cell wall.

Full.Cream:

[quote=\"Tang\"] Hi,

Why is there a need to describe the cell wall?

I will just answer as follows:

Plants have cell walls.

or

Plants have cell walls that give them regular shape.

Thinking the same thing here...is it necessary to give additional info/description? What is the context of the qn?

[/quote]
Hi,

The cell wall gives the plant a regular shape.

or

The cell wall gives the plant a good shape.

[Full.010894Cream]

think my boy was taught not to use ‘regular’ in description as it is too subjective.

[Joy]

Tang:

Leanne:

state the function of the cell wall.


The answer is as above.

We are discussing whether fixed or rigid is a better answer.Teacher wants fixed and not rigid but most guide book or internet, we see RIGID.

Anyway, teacher feels its wrong to use rigid.
[quote=\"Full.Cream\"]Thinking the same thing here...is it necessary to give additional info/description? What is the context of the qn?

Hi,

The cell wall gives the plant a regular shape.

or

The cell wall gives the plant a good shape.[/quote]

[atutor2001]

Leanne:

I got a reply from her teacher:


In Science, the specific meanings of the words is important.
Different adjectives means different things in Science.
According to Longman, the word rigid means \"stiff, not moving or bending\" - a movement.
However, we are looking for the inability of the cell to change shape - because it has been fixed by the cell wall.

He he he. The teacher's \"England very good.\" (Just added : \"fixed by the cell wall\" cannot be written as \"fixed cell wall\")

I have googled the common meanings of \"fixed\" shown below :
1. Firmly in position; stationary
2. established; settled; set (e.g. at a fixed time; a fixed price)

As for \"rigid\", the meanings are :
1. Not flexible or pliant; stiff
2. Not moving; fixed

Under normal usage, \"fixed\" used as an adjective often means (1) \"fastened - no change in position\" or (2) \"no change in quantity\". If we want to say that the shape of something does not change, then for clarity we should say \"cell wall has fixed SHAPE\".

Therefore, if we use the term \"fixed cell wall\", it could mean that the (1) position of the cell wall does not move, (2) the quantity of cell wall does not change. Science is rigorous - such alternative interpretations must be avoided.

On the other hand, \"rigid\" effectively means that the shape does not change. Therefore, it is more appropriate to use \"rigid cell wall\" if we want to communicate that the shape of the cell wall does not change.

In the good old days, my kids' science teachers hate me. They always got me wrong, thinking that I was hard up for the marks - explaining that it is difficult for them to change the marks after they were cornered. It really makes me mad when they give \"crab\" explanation without any thoughts at all - teaching the wrong concept.