Q&A - P5 Science

[marstolive]

Hi, can any kind soul help me with this question? Thanks in advance.


Hi, can someone help me with this question? Thanks in advance.

When a cell in placed in a salt solution, it shrivels as water moves out. When it is placed in water, it swells as water enters.

Jim was given some specimens of a certain type of cell. He placed the cells specimen into two different beakers, containing liquid A and liquid B respectively. He then viewed the specimens under a microscope. He recorded the observations made in the chart below.

Observation of cell under the microscope
IN liquid A, the liquid turned red and there was no sign of the cells.
In liquid B, the cells looked all crumpled up.

What could liquid A and B possibly be?

[Sun_2010]

marstolive:

Hi, can any kind soul help me with this question? Thanks in advance.


Hi, can someone help me with this question? Thanks in advance.

When a cell in placed in a salt solution, it shrivels as water moves out. When it is placed in water, it swells as water enters.

Jim was given some specimens of a certain type of cell. He placed the cells specimen into two different beakers, containing liquid A and liquid B respectively. He then viewed the specimens under a microscope. He recorded the observations made in the chart below.

Observation of cell under the microscope
IN liquid A, the liquid turned red and there was no sign of the cells.
In liquid B, the cells looked all crumpled up.

What could liquid A and B possibly be?

A = water.
The cells absorbed water , swelled and burst.
B = salt water

[marstolive]

Thanks for your help, Sun-2010! :goodpost:

[Jamesbond]

http://i42.tinypic.com/20jgsa1.jpg\">

Pl answer with explanation....TIA.

[dioprem]

Jamesbond:

http://i42.tinypic.com/20jgsa1.jpg\">

Pl answer with explanation....TIA.

Option A is wrong as the pollen does not travel down with the pollen tube. Rather a pollen tube grows downwards from the pollen grain. The male reproductive cells are at the bottom of the pollen tube.

Option B is correct as that is the mechanism where the pollen grain germinates. The pollen tube attempts to grow towards the ovary where the ovules are contained.

Option C is also correct as the very definition of fertilisation is when the male sex cell fuses with the female sex cell.

So the answer would be (3). Hope this helps

[Jamesbond]

dioprem:

Jamesbond:

http://i42.tinypic.com/20jgsa1.jpg\">

Pl answer with explanation....TIA.

Option A is wrong as the pollen does not travel down with the pollen tube. Rather a pollen tube grows downwards from the pollen grain. The male reproductive cells are at the bottom of the pollen tube.

Option B is correct as that is the mechanism where the pollen grain germinates. The pollen tube attempts to grow towards the ovary where the ovules are contained.

Option C is also correct as the very definition of fertilisation is when the male sex cell fuses with the female sex cell.

So the answer would be (3). Hope this helps

Thanks for ur great help...

[Jamesbond]

http://i44.tinypic.com/34spb1l.jpg\">

Pl answer with explanation....TIA.

[dioprem]

Jamesbond:

http://i44.tinypic.com/34spb1l.jpg\">

Pl answer with explanation....TIA.

Firstly for a flower to develop into a fruit, fertilisation must occur. Since that did not occur in groups C and D, the flowers will not develop into fruits. So options (3) and (4) are wrong.

In the case of group B, the ovules were removed. Strictly speaking fertilisation should not even occur as the female sex cells are in the ovules. The option is not phrased accurately.

Hence the best answer would be (1). The anthers produce the pollen grains. However the flowers were dusted from an external source of pollen grains. Hence fertilisation can still occur even though the anthers were removed.

Remember that for a flower to develop into a fruit, it must have the female parts. The male parts of the flower need not be present.

[Jamesbond]

dioprem:

Jamesbond:

http://i44.tinypic.com/34spb1l.jpg\">

Pl answer with explanation....TIA.

Firstly for a flower to develop into a fruit, fertilisation must occur. Since that did not occur in groups C and D, the flowers will not develop into fruits. So options (3) and (4) are wrong.

In the case of group B, the ovules were removed. Strictly speaking fertilisation should not even occur as the female sex cells are in the ovules. The option is not phrased accurately.

Hence the best answer would be (1). The anthers produce the pollen grains. However the flowers were dusted from an external source of pollen grains. Hence fertilisation can still occur even though the anthers were removed.

Remember that for a flower to develop into a fruit, it must have the female parts. The male parts of the flower need not be present.

Thanks a lot Dioperm....

[Jamesbond]

Why do filaments lengthen?

For the above section B question, what is the correct answer? Pl help…