Why is DNA copying an essential
[question] Question. Why is DNA copying an essential part of the process of reproduction? [/question] [solution] solution: Basic event in reproduction is production of DNA copies in a reproducing cell. The process is called DNA replication. When the cell divides into two, each new cell gets a copy of each DNA or chromosome along with the whole cellular apparatus. Complete accuracy in DNA copying leads to two exactly identical cells but any error in duplication can lead to dissimilar cells or var...
Read More →Explain the following in terms of gain or loss of oxygen with two examples each. (a) Oxidation (b) Reduction
Question: Explain the following in terms of gain or loss of oxygen with two examples each. (a) Oxidation (b) Reduction Solution: (a) Oxidation is the gain of oxygen. For example, In equation (i), $\mathrm{H}_{2}$ is oxidized to $\mathrm{H}_{2} \mathrm{O}$ and in equation (ii), $\mathrm{Cu}$ is oxidised to $\mathrm{CuO}$. (b) Reduction is the loss of oxygen. For example, In equation (i), $\mathrm{CO}_{2}$ is reduced to $\mathrm{CO}$ and in equation (ii), $\mathrm{CuO}$ is reduced to $\mathrm{Cu}$...
Read More →Why is vegetative propagation practised
[question] Question. Why is vegetative propagation practised for growing some types of plants? [/question] [solution] solution: There are several reasons for which vegetative propagation is favoured. They are as follows : (i) Either they do not produce seeds or their seeds are not viable. (ii) Their qualities are good and we want to preserve those qualities. (iii) Only male or female plant is available (iv) Fast growth. [/solution]...
Read More →How are the criteria for deciding divisions
[question] Question. How are the criteria for deciding divisions in plants different from the criteria for deciding the subgroups among animals? [/question] [solution] Solution: Criteria for deciding divisions in plants are: (i) Differentiated/Undifferentiated plant body (ii) Presence/ absence of vascular tissues (iii) With/without seeds (iv) Naked seeds/ seeds inside fruits Criteria for decidıng subgroups among animals are: Kingdom Animalia is divided into two major groups on the basis of the p...
Read More →Fe2O3 + 2Al Al2O3 + 2Fe The above reaction is an example of a
Question: $\mathrm{Fe}_{2} \mathrm{O}_{3}+2 \mathrm{Al} \rightarrow \mathrm{Al}_{2} \mathrm{O}_{3}+2 \mathrm{Fe}$ The above reaction is an example of a (1) Combination reaction. (2) Double displacement reaction. (3) Decomposition reaction. (4) Displacement reaction. Solution: The given reaction is an example of a displacement reaction....
Read More →Can you think of reasons why more complex organisms
[question] Question. Can you think of reasons why more complex organisms cannot give rise to new individuals through regeneration? [/question] [solution] solution: As the organisms become more and more complex they lose the property of regeneration. So they fail to regenerate. [/solution]...
Read More →How will an organism be benefited if it
[question] Question. How will an organism be benefited if it reproduces through spores? [/question] [solution] solution: (i) Spores are protected by hard covering which can tolerate hardship of environmental conditions. (ii) Being light weight they can be carried away by air and water currents to new locations where on germination give rise to new individuals. [/solution]...
Read More →How does binary fission differ from
[question] Question. How does binary fission differ from multiple fission? [/question] [solution] solution: In binary fission, one nucleus divides only once and results into the formation of two daughter nuclei but in multiple fission, the nucleus undergo repeated cell division resulting many nuclei. So, in binary fission only two daughter cells are produced but in multiple fission many cells are produced. [/solution]...
Read More →What are the major divisions in the Plantae?
[question] Question. What are the major divisions in the Plantae? What is the basis for these divisions? [/question] [solution] Solution: The kingdom Plantae is divided into five main divisions: Thallophyta, Bryophyta, Pteridophyta, Gymnosperms, and Angiosperms. The classification depends on the following criteria:Differentiated/ Undifferentiated plant body Presence /absence of vascular tissues With/ without seeds Naked seeds/ seeds inside fruits (i) The first level of classification depends on ...
Read More →Why is variation beneficial to the species
[question] Question. Why is variation beneficial to the species but not necessarily for the individual? [/question] [solution] solution: A particular variation in an individual may not be suitable for any given condition but when condition changes such variation may save it from being dead and leads to form a new population with suitable character. [/solution]...
Read More →What is the importance of DNA
[question] Question. What is the importance of DNA copying in reproduction? [/question] [solution] solution: DNA copying is important phenomena through which organism pass their character to offspring and produce variation. [/solution]...
Read More →Explain the basis for grouping organisms into five kingdoms.
[question] Question. Explain the basis for grouping organisms into five kingdoms. [/question] [solution] Solution: R.H. Whittaker proposed a five kingdom classification of living organisms on the basis of Linnaeus' system of classification. The five kingdoms proposed by Whittaker are Monera, Protista, Fungi, Plantae, and Animalia. The basis for grouping organisms into five kingdoms is as follows: (1) On the basis of the presence or absence of membrane-bound organelles, all living organisms are d...
Read More →What is the difference between the manner
[question] Question. What is the difference between the manner in which movement takes place in a sensitive plant and the movement in our legs ? [/question] [solution] solution: Movement takes place in sensitive plant due to turgor changes (changes in amount of water) which is effected by phytohormones. But movement in our leg is a voluntary action under the control of our will. Such movement are controlled by hind brain. [/solution]...
Read More →Compare and contrast nervous and hormonal mechanisms
[question] Question. Compare and contrast nervous and hormonal mechanisms for control and coordination in animals. [/question] [solution] solution: [/solution]...
Read More →How would you choose between
[question] Question. How would you choose between two characteristics to be used for developing a hierarchy in classification? [question] [solution] Solution: For developing a hierarchy of classification, we choose the fundamental characteristic among several other characteristics. For example, plants differ from animals in the absence of locomotion, chloroplasts, cell wall, etc. But, only locomotion is considered as the basic or fundamental feature that is used to distinguish between plants and...
Read More →How are involuntary actions and reflex actions
[question] Question. How are involuntary actions and reflex actions different from each other ? [/question] [solution] solution: Reflex actions are sudden, unconscious automatic response to some change in environment. It is controlled by spinal cord. On the other hand, involuntary actions also occur without the will of animals but these actions are controlled by either mid brain or hind brain. [/solution]...
Read More →What is the need for a system of control
[question] Question. What is the need for a system of control and coordination in an organisms ? [/question] [solution] solution: Multicellular organisms have diverse structure and functions. There are different system which perform specific function but the functioning of one system is not independent from the other. There is integration of all functional acitivities of the organism. For example, digestive enzymes are secreted into the food canal only when there is a food. The integration is po...
Read More →What are the advantages of classifying organisms?
[question] Question. What are the advantages of classifying organisms? [question] [solution] Solution: There are a wide range of life forms (about 10 million- 13 million species) around us. These life forms have existed and evolved on the earth over millions of years ago. The huge range of these life forms makes it very difficult to study them one by one. Therefore, we look for similarities among them and classify them into different classes so that we can study these different classes as a whol...
Read More →Solve the following pair of equations by the elimination method and the substitution method :
[question] Question. Solve the following pair of equations by the elimination method and the substitution method : (i) x + y = 5 and 2x – 3y = 4 (ii) 3x + 4y = 10 and 2x – 2y = 2 (iii) 3x – 5y – 4 = 0 and 9x = 2y + 7 (iv) $\frac{\mathbf{x}}{\mathbf{z}}+\frac{\mathbf{2} \mathbf{y}}{\mathbf{3}}=-\mathbf{1}$ and $x-\frac{\mathbf{y}}{\mathbf{3}}=3$ [/question] [solution] Solution: (i) Solution By Elimination Method: x + y = 5 ...(i) 2x – 3y = 4 ...(ii) Multiplying (i) by 3 and (ii) by 1 and adding w...
Read More →What are the differences between animals belonging
[question] Question. What are the differences between animals belonging to the Aves group and those in the mammalia group? [/question] [solution] Solution: [/solution]...
Read More →Which signals will get disrupted in
[question] Question. Which signals will get disrupted in case of a spinal cord injury ? [/question] [solution] solution: Spinal cord is an important component of Central Nervous system. It serves as a two way conduction path between peripheral nervous system and brain. The controlling centres in different areas of spinal cord function as reflex centres which control all the spinal reflexes. An injury in the spinal cord will disrupt the reflexes. The part of the body affected will depend upon the...
Read More →What are the differences between amphibians and reptiles?
[question] Question. What are the differences between amphibians and reptiles? [question] [solution] Solution: [solution]...
Read More →How does phototropism occur in plants ?
[question] Question. How does phototropism occur in plants ? [/question] [solution] solution: The response of a plant towards light is called as phototropism. If the plant part moves towards light, it is called positive phototropism. however, if the plant part moves away from light, then it is called negative phototropism. The stem (or shoot) of a growing plant bends towards light, so the stem (or shoot) of plant shows positive phototropism. On the other hand, the roots of a plant move away from...
Read More →Draw the structure of a neuron and explain its function.
[question] Question. Draw the structure of a neuron and explain its function. [/question] [solution] solution: Function of a neuron : (i) It helps in conducting impulses which enables the organism to show responses towards the stimuli. (ii) It helps in regulating control and coordination in animals. [/solution]...
Read More →How do annelid animals differ from arthropods?
[question] Question. How do annelid animals differ from arthropods? [question] [solution] Solution: [solution]...
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