1. In 1838, ____ , a German botanist, examined a large number of plants and observed that all plants are composed of different kinds of cells which form the tissues of the plant.
Correct Answer: B
1. Cell theory was developed by scientists.<br>2. Matthias Schleiden was a German botanist.<br>3. In 1838, he studied plants.<br>4. He examined many plant samples.<br>5. He observed that plants are made of cells.<br>6. These cells form tissues.<br>7. This was an important discovery.<br>8. It contributed to cell theory.<br>9. It explained plant structure.<br>10. Thus, Schleiden stated plants are made of cells.
2. At about the same time, ____ , a German Zoologist, studied different types of animal cells and reported that cells had a thin outer layer which is today known as the ‘plasma membrane’.
Correct Answer: C
1. Cell theory was developed by scientists.<br>2. Theodore Schwann was a zoologist.<br>3. In 1839, he studied animal cells.<br>4. He examined different types of cells.<br>5. He observed a thin outer layer.<br>6. This layer surrounds the cell.<br>7. It is now called plasma membrane.<br>8. This was an important discovery.<br>9. It contributed to cell theory.<br>10. Thus, Schwann described the plasma membrane.
3. Theodore Schwann also concluded that the presence of ____ is a unique character of the plant cells.
Correct Answer: B
1. Theodore Schwann studied plant and animal cells.<br>2. He compared their structures.<br>3. He observed that plant cells have an extra layer.<br>4. This layer is called the cell wall.<br>5. Animal cells do not have this structure.<br>6. Hence, it is unique to plant cells.<br>7. It provides support and protection.<br>8. It helps maintain shape.<br>9. This was an important conclusion.<br>10. Thus, cell wall is unique to plant cells.
4. On the basis of this, Schwann proposed the hypothesis that the bodies of ____ are composed of cells and products of cells.
Correct Answer: B
1. Schwann studied both plant and animal cells.<br>2. He compared their structures.<br>3. He found similarities between them.<br>4. Based on this, he proposed a hypothesis.<br>5. He stated that organisms are made of cells.<br>6. This included both plants and animals.<br>7. Cells form the body and its products.<br>8. This idea contributed to cell theory.<br>9. It unified biology concepts.<br>10. Thus, animals and plants are composed of cells.
5. ____ together formulated the cell theory.
Correct Answer: B
1. Cell theory is a fundamental concept in biology.<br>2. It explains that all organisms are made of cells.<br>3. Matthias Schleiden studied plant cells.<br>4. Theodore Schwann studied animal cells.<br>5. Both shared similar conclusions.<br>6. They combined their ideas.<br>7. Together, they formulated cell theory.<br>8. It became a major scientific principle.<br>9. It applies to all living organisms.<br>10. Thus, Schleiden and Schwann proposed cell theory.
6. This theory however, did not explain as to how ____ cells were formed.
Correct Answer: B
1. Cell theory explained that organisms are made of cells.<br>2. It was proposed by Schleiden and Schwann.<br>3. However, it had a limitation.<br>4. It did not explain cell origin.<br>5. Scientists did not know how cells are formed.<br>6. The formation of new cells was unclear.<br>7. This gap was later addressed.<br>8. Virchow explained cell division.<br>9. He stated cells arise from pre-existing cells.<br>10. Thus, the theory did not explain formation of new cells.
7. ____ (1855) first explained that cells divided and new cells are formed from pre-existing cells (Omnis cellula-e cellula).
Correct Answer: B
1. Early cell theory did not explain origin of cells.<br>2. This gap was later filled by a scientist.<br>3. Rudolf Virchow proposed an idea in 1855.<br>4. He stated that cells divide.<br>5. New cells come from existing cells.<br>6. This idea is called 'Omnis cellula-e cellula'.<br>7. It means every cell arises from another cell.<br>8. This completed cell theory.<br>9. It is a fundamental principle.<br>10. Thus, Virchow explained origin of cells.
8. ____ modified the hypothesis of Schleiden and Schwann to give the cell theory a final shape.
Correct Answer: B
1. Schleiden and Schwann proposed cell theory.<br>2. It had a limitation about origin of cells.<br>3. Rudolf Virchow addressed this issue.<br>4. He stated that new cells arise from existing cells.<br>5. This idea completed the theory.<br>6. He modified the earlier hypothesis.<br>7. This gave final shape to cell theory.<br>8. It became widely accepted.<br>9. It is a fundamental concept.<br>10. Thus, Virchow finalized the cell theory.
9. Cell theory as understood today is: (i) ____ (ii) ____.
Correct Answer: B
1. Cell theory explains basic facts about cells.<br>2. It states all organisms are made of cells.<br>3. Cells are the basic units of life.<br>4. Organisms are composed of cells and their products.<br>5. Cells do not arise spontaneously.<br>6. New cells come from existing cells.<br>7. This was explained by Virchow.<br>8. These statements form modern cell theory.<br>9. It is widely accepted.<br>10. Thus, organisms are made of cells and cells arise from pre-existing cells.
