J. Long answer questions
1. What does the cell theory state? 2. Are multicellular organisms advanced as compared to the unicellular organisms? Give three reasons in support of your answer. 3. Explain the structure of the nucleus with the help of a labelled diagram.
4. What are plastids? Write an account on the different types of plastids found in plants.
5. Draw a labelled diagram of a typical animal cell.
6. Differentiate between a plant cell and an animal cell.
pls tell all answer and fast please
Answers
1. The cell theory that all the plants and animals are composed of cells and the cell is the basic unit of life, was presented by two biologists, Schleiden (1838) and Schwann (1839). In 1855, a German physiologist, Rudolf Virchow added a third principle to the cell theory. He gave the phrase, 'Omnis cellula-e-cellula', i.e., all cells arise from pre-existing cells. Later, discoveries led to the modification of cell theory. Modified cell theory is termed as cell principle or modern cell theory which postulates that all living organisms are composed of cells or cell products and arise from pre-existing cells. All cells are basically alike in chemical composition and metabolic processes.
2. Unicellular organism are the organisms with 1 cell whereas multicellular organisms are the organisms with more than one cell
* Unicellular organisms only one cell can carry out all the biological processes in life whereas in multicellular there are specific cells to perform various biological processes
*total cell is exposed to environment whereas in multicellular cell has a covering multicellulars have complex body structure
*lifespan is short of unicellular and life span is more of multicellular
*unicellular - amoeba
*multicellular - humans
multicellular organisms are more capable of doing complex things and perform difficult tasks throughout there life because there are specific organs in their body yo perform specific tasks and hence the labour division of work is easy and can go on for hours without tiring.
3.
