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A person has suffered paralysis of the right side of the body. Which part of the brain is likely damaged? Draw a labelled diagram of the human brain and explain.
ANSWER: Paralysis of the right side of the body usually indicates damage to the left hemisphere of the cerebrum. The cerebrum controls voluntary actions, learning, memory, and thinking. Each hemisphere controls opposite sides of the body, so damage to the left affects the right side. The motor areaRead more
ANSWER: Paralysis of the right side of the body usually indicates damage to the left hemisphere of the cerebrum. The cerebrum controls voluntary actions, learning, memory, and thinking. Each hemisphere controls opposite sides of the body, so damage to the left affects the right side. The motor area of the cerebrum sends signals to muscles for movement. If injured, nerve impulses cannot pass, causing paralysis.
See lessIn a pea plant, the trait of flowers bearing purple colour (PP) is a dominant over white colour (pp). Explain the inheritance pattern of F₁ and F₂ generations with the help of a cross following the rules of inheritance of traits. State the visible characters of F₁ and F₂ progenies.
ANSWER: In pea plants, purple flower (P) is dominant over white (p). When a pure purple (PP) is crossed with a pure white (pp), all F₁ generation plants are Pp, showing purple flowers, as the dominant trait masks the recessive one. When two F₁ plants (Pp × Pp) are self-crossed, the F₂ generation shoRead more
ANSWER: In pea plants, purple flower (P) is dominant over white (p). When a pure purple (PP) is crossed with a pure white (pp), all F₁ generation plants are Pp, showing purple flowers, as the dominant trait masks the recessive one. When two F₁ plants (Pp × Pp) are self-crossed, the F₂ generation shows a genotypic ratio of 1 PP: 2 Pp: 1 pp and a phenotypic ratio of 3 purple: 1 white.
See lessHow can a man survive with one kidney?
ANSWER: A man can survive with one kidney because a single kidney is capable of performing all essential functions of filtration and excretion. Each kidney contains about one million nephrons, and even one kidney can efficiently remove urea, excess salts, and water from the blood. The remaining kidnRead more
ANSWER: A man can survive with one kidney because a single kidney is capable of performing all essential functions of filtration and excretion. Each kidney contains about one million nephrons, and even one kidney can efficiently remove urea, excess salts, and water from the blood. The remaining kidney compensates by working harder and often enlarges slightly.
However, the person must maintain a healthy lifestyle, avoid overuse of medicines, reduce protein and salt intake, and prevent infections to keep the single kidney functioning properly.
See lessWhat is haemodialysis? Mention its need, procedure, and limitations. Give two precautions a patient undergoing dialysis must follow.
ANSWER: Haemodialysis: Haemodialysis is a medical process in which an artificial kidney (dialysis machine) is used to remove waste products like urea, extra salts, and water from the blood when kidneys fail to function properly. Need: It is required in patients suffering from kidney failure or severRead more
ANSWER: Haemodialysis: Haemodialysis is a medical process in which an artificial kidney (dialysis machine) is used to remove waste products like urea, extra salts, and water from the blood when kidneys fail to function properly.
Need: It is required in patients suffering from kidney failure or severe damage, where the natural kidneys cannot purify blood effectively.
Procedure: The patient’s blood is passed through a dialyser containing a semi-permeable membrane. Wastes and toxins diffuse into the dialysing fluid, and purified blood is returned to the body.
Limitations: Dialysis is expensive, time-consuming, and only a temporary solution. It cannot replace all the functions of healthy kidneys.
Precautions: Patients must follow a low-salt, low-protein diet and take strict care to avoid infections during and after dialysis.
See lessBanana plants are generally propagated through vegetative methods. (i) Why is seed propagation not used in bananas? (ii) Explain the process of vegetative propagation in banana. (iii) List one advantage and one disadvantage of this method. (iv) If a disease affects the parent banana plant, will it also spread to the offspring? Why?
ANSWER: (i) Seed propagation is not commonly used in bananas because most edible varieties are seedless and sterile, making their seeds either absent or non-viable. Hence, they cannot be grown in large numbers through seeds, so farmers use vegetative propagation. (ii) In this method, new banana planRead more
ANSWER:
(i) Seed propagation is not commonly used in bananas because most edible varieties are seedless and sterile, making their seeds either absent or non-viable. Hence, they cannot be grown in large numbers through seeds, so farmers use vegetative propagation.
(ii) In this method, new banana plants are produced from suckers or rhizomes that grow near the base of the parent plant. When these suckers are separated and planted in soil, they develop into fully grown banana plants. This method is quick and reliable for large-scale production.
(iii) Advantage: Vegetative propagation ensures that all new plants are genetically identical, showing the same desired qualities.
Disadvantage: However, the lack of variation makes them prone to diseases.
(iv) If a parent plant suffers from a disease, the same disease easily spreads to its offspring because they are clones.
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