Nota Terkini

Tuesday, April 21, 2009

[Biology Form 4] Animal Cell & Plant Cell

The cell is the basic unit of all organism. It is made up of a cell membrane that encloses the cytoplasm.

Contained within the cytoplasm are not only the
nucleus but also organelles, whose specific functions help the cell perform a range of activities.

While plant and animal cells are similar, the plant cell has, in addition to the cell membrane, another boundary that separates it from its external environment. This is called the
cell wall.

As most plant cells carry out photosynthesis - the synthesis of organic substances - they contain
chloroplasts.

In plant cells,
vacuoles also tend to be larger in size and smaller in number than those found in animal cells.

Onion Skin Cell

Cheek Squamous Epithelial Cells

Typical Plant Cell

Typical Animal Cell


In the laboratory, you have learned how to prepare a microscope slide of human cheek cells as well as the epidermal cells of onions.

a) The differences you can observe between the two types of cells in term of the following:
  • Shape
    Onion cells have a regular shape while cheek cells have an irregular shape.

  • Presence or absence of cell wall
    Onion cells have a cell wall while cheek cells do not.

  • Presence or absence of vacuoles
    Onion cells have a large vacuole while vacuoles in cheek cells, if present, are small.
b) Can you observe chloroplasts in the epidermal cells of onions? Explain your answer.
No chloroplasts can be observed in the epidermal cells of onions because epidermal cells do not carry out photosynthesis.

12 comments:

  1. Cikgu, takde bahasa Melayuke kesian bahasa kita perlukan terjemahan yang banyak seluruh ilmu.

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  2. bestnye..ade note kat sini..hehe

    ReplyDelete
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    ReplyDelete
  4. thanx cikgu it is very useful for me

    ReplyDelete
  5. this is my life saviour!!!
    thx a lot....

    ReplyDelete
  6. techer,i nid ur help related 2 a F4C2 ques..cn u help me 2 describe how the size of an organism influences the function of contractile vacuole..i hope u cn help me by answering this question..tq 4 ur kind notes..

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  7. thanx u cikgu cause snangkan keje saye...he3...

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  8. cikgu..note ni cam baguish jek..x oleh ke sye download?

    ReplyDelete
  9. wah bagus2 thank cikgu
    sebenarnya cikgu skool saya suruh bukak ni

    ReplyDelete
  10. what means of biochemical reation of cell??is that means growth of the cell??=)

    ReplyDelete
  11. Terbaik ah, senang nak buat nota. hehehe

    ReplyDelete