cell structure and functions (POST 1)

Good morning boys! Welcome to the first class of science.
The lesson we are going to study is  - CELL-STRUCTURE AND FUNCTIONS.
You have learnt in your earlier classes that
. CELL is the basic structural and functional unit of life.

LEARNING OUTCOMES OF THIS CLASS
By the end of this lesson you will be able to-
.name the scientist who discovered cell.
.distinguish between unicellular and multicellular organisms
.give examples of unicellular and multicellular organisms

 All livings things are made up of cells that are so tiny that they can only be seen under a microscope. Cell was discovered by ROBERT HOOKE,when he was observing thin slices of cork under a microscope.
A single cell is capable of performing all biological activities in any living organism.

 DEPENING ON THE NUMBER OF CELLS ORGANISMS CAN BE GROUPED AS FOLLOWS-
# UNICELLULAR ORGANIMS - These are organisms that consist of only one cell . Example, amoeba
# MULTICELLULAR ORGANISMS- These are organisms that consist of many cells . Examples-algae, plants,animals.

 CELLS DIFFER IN SIZE-
In multicellular organisms cells differ in size. For example
- The egg of an ostrich is about 7 cm ( it is the largest )
-The unicellular  alga ,Acetabularia , has a length of 10cm.
Remember ! THE SIZE OF A CELL HAS NO RELATIONSHIP WITH THE BODY SIZE OF THE ORGANISM , it is only related to its function. For example, the nerve cells, both in rat and elephant are long and branched and perform the same function.

 DIIFERENT CELLS HAVE DIFFERENT SHAPES ( the shape of a cell is related to its function)

For example AMOEBA is irregular in shape , NERVE cell is long , branched  and has thread like projections.

 https://youtu.be/vduncK7yMsQ

 HOMEWORK

1. Read pages126-128 of your reader.
2. Learn the definitions of (i) cell  ( ii) unicellular organisms (iii ) multicellular organisms

Comments

  1. PreetikaApril 1, 2020 at 8:38 AM

    Good morning boys...Work to be done in the notebook will be sent in the evening .

    ReplyDelete
  2. PreetikaApril 1, 2020 at 8:38 AM

    Good morning boys...Work to be done in the notebook will be sent in the evening .

    ReplyDelete
  3. Akshat RauthanApril 1, 2020 at 8:39 AM

    Good morning ma'am I'm akshat Rauthan

    ReplyDelete
  4. ROHANApril 1, 2020 at 8:42 AM

    Good morning ma'am i am Rohan Bisht

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  5. Varun negiApril 1, 2020 at 8:43 AM

    Good morning Ma'am my name is varun negi

    ReplyDelete
  6. AlenApril 1, 2020 at 8:43 AM

    Good morning ma'am. I'm ALEN SALVI

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  7. Ronak pkApril 1, 2020 at 8:44 AM

    Good morning ma,am I am ronak pk

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  8. AnasApril 1, 2020 at 8:45 AM

    Good morning mam Anas Ahmad here

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  9. UnknownApril 1, 2020 at 8:45 AM

    Good morning mam am Prabhgun Singh Chopra

    ReplyDelete
  10. AnasApril 1, 2020 at 8:46 AM

    Good morning mam Anas Ahmad here

    ReplyDelete
  11. AmaanApril 1, 2020 at 8:51 AM

    Good morning ma'am I am Amaan Richard

    ReplyDelete
  12. Akash DcostaApril 1, 2020 at 8:52 AM

    Good morning mam I am Akash Dcosta

    ReplyDelete
  13. Ronak pkApril 1, 2020 at 8:53 AM

    Good morning ma,am I am ronak pk

    ReplyDelete
  14. Ojas punjApril 1, 2020 at 8:53 AM

    Good morning ma'am . I'm Ojas Punj

    ReplyDelete
  15. Achyut TripathiApril 1, 2020 at 8:54 AM

    Good morning Ma'am.
    I am Achyut Tripathi of class 8D

    ReplyDelete
  16. Ojas SabherwalApril 1, 2020 at 8:55 AM

    God morning ma’a I am Ojas Sabherwal

    ReplyDelete
  17. JoelApril 1, 2020 at 8:58 AM

    Good morning mam I am Tumeti Sushaun Joel

    ReplyDelete
  18. Vishnu VardhanApril 1, 2020 at 8:58 AM

    Good morning mam I am vishnu

    ReplyDelete
  19. UnknownApril 1, 2020 at 8:58 AM

    Good morning mam am Prabhgun Singh Chopra

    ReplyDelete
  20. Mohd Zulqar NainApril 1, 2020 at 8:59 AM

    Good morning mam, I am Zulqar nain

    ReplyDelete
  21. DeependraApril 1, 2020 at 9:01 AM

    Good morning mam. This is DEEPENDRA KUMAR SINGH.

    ReplyDelete
  22. Mohit KumarApril 1, 2020 at 9:03 AM

    Good Morning Mam. Mohit Kumar,.8D

    ReplyDelete
  23. Krishna GhoshApril 1, 2020 at 9:04 AM

    Good morning mam.I am krishna ghosh of class 8D

    ReplyDelete
  24. Janav jainApril 1, 2020 at 9:04 AM

    Good morning Ma’am I am Janav Jain

    ReplyDelete
  25. Riddhesh S. LodhiApril 1, 2020 at 9:06 AM

    Good morning ma'am I am Riddhesh S. Lodhi

    ReplyDelete
  26. JonathanApril 1, 2020 at 9:07 AM

    Good morning Ma'm, I am Jonathan

    ReplyDelete
  27. Ashaan Anurag lallApril 1, 2020 at 9:12 AM

    Good morning mam I am Ashaan Anurag lall

    ReplyDelete
  28. Ronald Jo JosephApril 1, 2020 at 9:14 AM

    Good morning Ma'am

    ReplyDelete
  29. PreetikaApril 1, 2020 at 9:36 AM

    A very good morning to all!

    ReplyDelete
  30. unknownApril 1, 2020 at 9:36 AM

    Good morning ma'am.My name is Hitesh Vijay Nitnaware.

    ReplyDelete
  31. Shaun DsouzaApril 1, 2020 at 9:42 AM

    Good morning sir, my name Shaun Dsouza

    ReplyDelete
  32. Maanvik SoodApril 1, 2020 at 10:16 AM

    Good morning ma'am I'm Maanvik Sood. I was not able to access the blog at the correct time since there was a problem with my internet

    ReplyDelete
  33. KartikApril 1, 2020 at 11:54 AM

    Good Morning Ma'am, I am Kartik of 8th D

    ReplyDelete
  34. Aditya JaisonApril 1, 2020 at 12:15 PM

    Good morning ma'am
    My name is Aarush

    ReplyDelete
  35. Jacob TombingApril 1, 2020 at 3:14 PM

    "HOMEWORK

    1. Read pages126-128 of your reader."


    Ma'am, I haven't got the book yet. Can you please provide scanned copies of these pages...

    ReplyDelete
  36. Daksh martinApril 1, 2020 at 6:35 PM

    Good morning mam im Daksh martin

    ReplyDelete
  37. Gurdev SinghApril 1, 2020 at 8:13 PM

    Good evening ma'am, I am gurdev singh, class 8D

    ReplyDelete
  38. Shaun DsouzaApril 3, 2020 at 9:42 AM

    Good morning, name is Shaun Dsouza

    ReplyDelete
  39. unknownApril 3, 2020 at 10:04 AM

    My name is Hitesh Vijay Ninaware.

    ReplyDelete
  40. JoelApril 3, 2020 at 10:19 AM

    Good morning ma'am I am Tumeti Sushaun Joel of class 8d

    ReplyDelete
  41. Arpit Jonathan PillayApril 3, 2020 at 10:57 AM

    I am Arpit Jonathan Pillay

    ReplyDelete
  42. Aadish Jain 8-DMay 25, 2020 at 2:26 PM

    Good morning mam

    ReplyDelete

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