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Directions: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:
Assertion : Holoblastic cleavage with almost equal sized blastomeres is a characteristic of placental animals.
Reason : Eggs of most mammals, including humans, are of centrolecithal type.
- a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
- b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
- c)Assertion (A) is true but reason (R) is false.
- d)Assertion (A) is false but reason (R) is true.
- e)Both Assertion and Reason are false.
Correct answer is option 'C'. Can you explain this answer?
Most Upvoted Answer
Directions: In the following questions, a statement of assertion (A) ...
Assertion: Holoblastic cleavage with almost equal sized blastomeres is a characteristic of placental animals.
Reason: Eggs of most mammals, including humans, are of centrolecithal type.
Explanation:
Assertion (A) is true but reason (R) is false.
Holoblastic cleavage refers to the type of cleavage that occurs in animal embryos where the entire zygote divides completely during cell division. In holoblastic cleavage, the blastomeres (cells formed after cleavage) are approximately equal in size.
Placental animals, also known as eutherians, are a group of mammals that give birth to fully developed young ones. They have a placenta, which is an organ that provides nourishment and oxygen to the developing embryo. Holoblastic cleavage with almost equal-sized blastomeres is indeed a characteristic of placental animals.
However, the reason provided is incorrect. The eggs of most mammals, including humans, are not of centrolecithal type. Centrolecithal eggs are characterized by a large central yolk surrounded by a thin layer of cytoplasm and a plasma membrane. This type of egg is found in insects and some other invertebrates.
Mammals, on the other hand, have either isolecithal or telolecithal eggs. Isolecithal eggs have a small amount of evenly distributed yolk, while telolecithal eggs have a large amount of yolk concentrated at one end of the egg. Humans have isolecithal eggs, which means that the yolk is evenly distributed throughout the cytoplasm.
Therefore, the reason provided does not correctly explain the assertion. The correct answer is option 'C' - Assertion (A) is true but reason (R) is false.
Reason: Eggs of most mammals, including humans, are of centrolecithal type.
Explanation:
Assertion (A) is true but reason (R) is false.
Holoblastic cleavage refers to the type of cleavage that occurs in animal embryos where the entire zygote divides completely during cell division. In holoblastic cleavage, the blastomeres (cells formed after cleavage) are approximately equal in size.
Placental animals, also known as eutherians, are a group of mammals that give birth to fully developed young ones. They have a placenta, which is an organ that provides nourishment and oxygen to the developing embryo. Holoblastic cleavage with almost equal-sized blastomeres is indeed a characteristic of placental animals.
However, the reason provided is incorrect. The eggs of most mammals, including humans, are not of centrolecithal type. Centrolecithal eggs are characterized by a large central yolk surrounded by a thin layer of cytoplasm and a plasma membrane. This type of egg is found in insects and some other invertebrates.
Mammals, on the other hand, have either isolecithal or telolecithal eggs. Isolecithal eggs have a small amount of evenly distributed yolk, while telolecithal eggs have a large amount of yolk concentrated at one end of the egg. Humans have isolecithal eggs, which means that the yolk is evenly distributed throughout the cytoplasm.
Therefore, the reason provided does not correctly explain the assertion. The correct answer is option 'C' - Assertion (A) is true but reason (R) is false.
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Directions: In the following questions, a statement of assertion (A) ...
Holoblastic type of cleavage with equal sized blastomeres is commonly seen in eggs containing moderate to sparse amount of yolk. It is characteristic of mammals.
Reason is incorrect as eggs of most mammals including humans are of alecithal, meaning negligible amount of yolk. Centrolecithal eggs are found in insects, where yolk is present at the center of the egg with cytoplasm around it.
Therefore, the correct answer is option C.
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Directions: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion : Holoblastic cleavage with almost equal sized blastomeres is a characteristic of placental animals.Reason : Eggs of most mammals, including humans, are of centrolecithal type.a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).c)Assertion (A) is true but reason (R) is false.d)Assertion (A) is false but reason (R) is true.e)Both Assertion and Reason are false.Correct answer is option 'C'. Can you explain this answer? for Class 10 2025 is part of Class 10 preparation. The Question and answers have been prepared according to the Class 10 exam syllabus. Information about Directions: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion : Holoblastic cleavage with almost equal sized blastomeres is a characteristic of placental animals.Reason : Eggs of most mammals, including humans, are of centrolecithal type.a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).c)Assertion (A) is true but reason (R) is false.d)Assertion (A) is false but reason (R) is true.e)Both Assertion and Reason are false.Correct answer is option 'C'. Can you explain this answer? covers all topics & solutions for Class 10 2025 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Directions: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion : Holoblastic cleavage with almost equal sized blastomeres is a characteristic of placental animals.Reason : Eggs of most mammals, including humans, are of centrolecithal type.a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).c)Assertion (A) is true but reason (R) is false.d)Assertion (A) is false but reason (R) is true.e)Both Assertion and Reason are false.Correct answer is option 'C'. Can you explain this answer?.
Directions: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion : Holoblastic cleavage with almost equal sized blastomeres is a characteristic of placental animals.Reason : Eggs of most mammals, including humans, are of centrolecithal type.a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).c)Assertion (A) is true but reason (R) is false.d)Assertion (A) is false but reason (R) is true.e)Both Assertion and Reason are false.Correct answer is option 'C'. Can you explain this answer? for Class 10 2025 is part of Class 10 preparation. The Question and answers have been prepared according to the Class 10 exam syllabus. Information about Directions: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion : Holoblastic cleavage with almost equal sized blastomeres is a characteristic of placental animals.Reason : Eggs of most mammals, including humans, are of centrolecithal type.a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).c)Assertion (A) is true but reason (R) is false.d)Assertion (A) is false but reason (R) is true.e)Both Assertion and Reason are false.Correct answer is option 'C'. Can you explain this answer? covers all topics & solutions for Class 10 2025 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Directions: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion : Holoblastic cleavage with almost equal sized blastomeres is a characteristic of placental animals.Reason : Eggs of most mammals, including humans, are of centrolecithal type.a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).c)Assertion (A) is true but reason (R) is false.d)Assertion (A) is false but reason (R) is true.e)Both Assertion and Reason are false.Correct answer is option 'C'. Can you explain this answer?.
Solutions for Directions: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion : Holoblastic cleavage with almost equal sized blastomeres is a characteristic of placental animals.Reason : Eggs of most mammals, including humans, are of centrolecithal type.a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).c)Assertion (A) is true but reason (R) is false.d)Assertion (A) is false but reason (R) is true.e)Both Assertion and Reason are false.Correct answer is option 'C'. Can you explain this answer? in English & in Hindi are available as part of our courses for Class 10.
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Here you can find the meaning of Directions: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion : Holoblastic cleavage with almost equal sized blastomeres is a characteristic of placental animals.Reason : Eggs of most mammals, including humans, are of centrolecithal type.a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).c)Assertion (A) is true but reason (R) is false.d)Assertion (A) is false but reason (R) is true.e)Both Assertion and Reason are false.Correct answer is option 'C'. Can you explain this answer? defined & explained in the simplest way possible. Besides giving the explanation of
Directions: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion : Holoblastic cleavage with almost equal sized blastomeres is a characteristic of placental animals.Reason : Eggs of most mammals, including humans, are of centrolecithal type.a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).c)Assertion (A) is true but reason (R) is false.d)Assertion (A) is false but reason (R) is true.e)Both Assertion and Reason are false.Correct answer is option 'C'. Can you explain this answer?, a detailed solution for Directions: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion : Holoblastic cleavage with almost equal sized blastomeres is a characteristic of placental animals.Reason : Eggs of most mammals, including humans, are of centrolecithal type.a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).c)Assertion (A) is true but reason (R) is false.d)Assertion (A) is false but reason (R) is true.e)Both Assertion and Reason are false.Correct answer is option 'C'. Can you explain this answer? has been provided alongside types of Directions: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion : Holoblastic cleavage with almost equal sized blastomeres is a characteristic of placental animals.Reason : Eggs of most mammals, including humans, are of centrolecithal type.a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).c)Assertion (A) is true but reason (R) is false.d)Assertion (A) is false but reason (R) is true.e)Both Assertion and Reason are false.Correct answer is option 'C'. Can you explain this answer? theory, EduRev gives you an
ample number of questions to practice Directions: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion : Holoblastic cleavage with almost equal sized blastomeres is a characteristic of placental animals.Reason : Eggs of most mammals, including humans, are of centrolecithal type.a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).c)Assertion (A) is true but reason (R) is false.d)Assertion (A) is false but reason (R) is true.e)Both Assertion and Reason are false.Correct answer is option 'C'. Can you explain this answer? tests, examples and also practice Class 10 tests.
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