In the following questions, a statement of Assertion (A) is followed by a statement of Reason.
Mark the correct choice as:
(a)If both A and R are true and R is the correct explanation of A
(b) If both A and R are true but R is not the correct explanation of A
(c) If A is true but R is false
(d) If both A and R are false
1. A: All organisms are made up of cells.
R: Cells are structural unit of living organisms. A cell keeps its chemical composition steady
within its boundary.
2. A: Specialization of cells is useful to organism.
R: It increases the operational efficiency of an organism.
3. A: Rudolf Virchow modified the hypothesis of cell theory given by Schleiden and
Schwann.
R: Cell theory states that all cells arise from pre-existing cells.
4. A: Ribosomes are non-membrane bound organelles found in the prokaryotic cells only.
R: They are present only in the cytoplasm.
5. A: Cell membrane is semipermeable.
R: The constituent molecules can freely move in the membrane.
6. A: Powerhouse of cell is mitochondria.
R: ATP is produced in mitochondria.
7. A: Meiosis is known as reductional division.
R: During meiosis, the chromosome number gets reduced by half of its number.
Answers
Explanation:
Given below is a conversation between two farmers Heera and Beera.
Heera: Brother Beera, your maize crops looks beautiful! They have grown pretty fast.
Beera: Yes, I have sprayed urea this time. What about you?
Heera: Well, I am still relying on good old cow dung. I am saving money for buying a
tractor.
Beera: That’s good. Tractor saves a lot of time and labour.
Heera: Yes, it’s been very labour intensive for me and now these weeds have come up.
Beera: Try weedicides, they are very effective.
Now answer the following questions.
(a) List the practices which are not environment friendly and why?
(b) What is the advantage of modern agriculture implements over traditional ones?
(c) Name one weedicide and the precaution farmers must take during its application.
P.s. Please answer it the following questions, a statement of Assertion (A) is followed by a statement of Reason.
Mark the correct choice as:
(a)If both A and R are true and R is the correct explanation of A
(b) If both A and R are true but R is not the correct explanation of A
(c) If A is true but R is false
(d) If both A and R are false
1. A: All organisms are made up of cells.
R: Cells are structural unit of living organisms. A cell keeps its chemical composition steady
within its boundary.
2. A: Specialization of cells is useful to organism.
R: It increases the operational efficiency of an organism.
3. A: Rudolf Virchow modified the hypothesis of cell theory given by Schleiden and
Schwann.
R: Cell theory states that all cells arise from pre-existing cells.
4. A: Ribosomes are non-membrane bound organelles found in the prokaryotic cells only.
R: They are present only in the cytoplasm.
5. A: Cell membrane is semipermeable.
R: The constituent molecules can freely move in the membrane.
6. A: Powerhouse of cell is mitochondria.
R: ATP is produced in mitochondria.
7. A: Meiosis is known as reductional division.
R: During meiosis, the chromosome to class 8 level
Answer:
(a) Both assertion (A) and reason (R) are true and reason is the correct explanation of assert