1. The hormone insulin, secreted by the pancreas, controls the level of glucose in the blood. When insulin production is insufficient, glucose is not converted into glycogen for storage, leading to high blood sugar levels. This condition is called diabetes mellitus. It causes fatigue, frequent urinatioRead more

    The hormone insulin, secreted by the pancreas, controls the level of glucose in the blood. When insulin production is insufficient, glucose is not converted into glycogen for storage, leading to high blood sugar levels. This condition is called diabetes mellitus. It causes fatigue, frequent urination, and increased thirst. Hence, the correct answer is insulin from the pancreas, as its lack is responsible for abnormally high glucose levels in the patient’s bloodstream. The correct option is (D).

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  2. The medulla oblongata, located in the hindbrain, is responsible for regulating involuntary activities like heartbeat, breathing, and blood pressure. It ensures that vital functions continue automatically without conscious control. The cerebrum controls voluntary actions, while pons and midbrain perfRead more

    The medulla oblongata, located in the hindbrain, is responsible for regulating involuntary activities like heartbeat, breathing, and blood pressure. It ensures that vital functions continue automatically without conscious control. The cerebrum controls voluntary actions, while pons and midbrain perform other specific functions. Therefore, the correct combination is Blood pressure: Medulla in hindbrain, as this region coordinates and maintains the rhythmic functioning of the heart and lungs, ensuring a steady flow of blood throughout the body. The correct option is (D).

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  3. In the absence of sufficient oxygen, our muscle cells undergo anaerobic respiration. In this process, glucose is partially broken down to form lactic acid and a small amount of energy is released. This lactic acid accumulates in muscles, causing pain and fatigue after heavy exercise. When enough oxyRead more

    In the absence of sufficient oxygen, our muscle cells undergo anaerobic respiration. In this process, glucose is partially broken down to form lactic acid and a small amount of energy is released. This lactic acid accumulates in muscles, causing pain and fatigue after heavy exercise. When enough oxygen becomes available, lactic acid is converted back to carbon dioxide and water. Thus, the correct answer is that lactic acid and energy are produced during anaerobic respiration in human muscle cells. The correct option is (B).

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  4. The correct answer is Cuscuta, ticks, lice, leeches, and tapeworm. All these organisms obtain food from other living beings, showing a parasitic mode of nutrition. Parasites absorb nutrients from the host’s body, harming it in the process. Cuscuta sucks nutrients from plants, while ticks, lice, leecRead more

    The correct answer is Cuscuta, ticks, lice, leeches, and tapeworm. All these organisms obtain food from other living beings, showing a parasitic mode of nutrition. Parasites absorb nutrients from the host’s body, harming it in the process. Cuscuta sucks nutrients from plants, while ticks, lice, leeches, and tapeworms live on or inside animals to absorb food. Unlike autotrophs, they cannot prepare their own food and depend entirely on their hosts for survival and nourishment. The correct option is (C).

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  5. (i) 12 Ω lamps (only) on. (a) 4 Ω lamps (only) on (ii) 12 V for both sets of lamps and all of them are in parallel. (iii) 12 Ω lamps are on when the wire is connected to position 2. Voltage across both 12 Ω lamps = 12 V. V = IR (Ohm’s law). I = 1A. 4 Ω lamps are on when the wire is connected to posiRead more

    (i) 12 Ω lamps (only) on.

    (a) 4 Ω lamps (only) on

    (ii) 12 V for both sets of lamps and all of them are in parallel.

    (iii) 12 Ω lamps are on when the wire is connected to position 2.

    Voltage across both 12 Ω lamps = 12 V.

    V = IR (Ohm’s law).

    I = 1A.

    4 Ω lamps are on when the wire is connected to position 3.

    Voltage across both 4 Ω lamps = 12 V.

    V=IR (Ohm’s law).

    I = 3A.

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