- ATo carry out photosynthesis.
- BTo regulate the opening and closing of stomata.
- CTo transport nutrients within the leaf.
- DTo provide structural support to the epidermis.
Guard cells are specialized epidermal cells that surround each stoma. Their primary role is to regulate the opening and closing of stomata, thereby controlling gas exchange (CO2 intake, O2 release) and the rate of transpiration.
More Questions on Life Processes
1What is the consequence of consuming alcohol on the functioning of the liver?
→ 2Which enzyme is responsible for the digestion of proteins in the stomach?
→ 3Why are decomposers essential for the continuation of life processes in an ecosystem?
→ 4In humans, where does the majority of enzymatic digestion and absorption of nutrients take place?
→ 5Which of the following is an example of an endothermic organism?
→ 6How do plants manage their excretory needs, considering they lack a specialized excretory system?
→ 7If the bile duct is blocked, what immediate effect would this have on the digestion of fats?
→ 8Which component of blood is responsible for defending the body against infections?
→ 9Why is it crucial for blood to follow a "double circulation" pathway in humans?
→ 10A scientist compares the rate of photosynthesis in two identical plants. Plant A is exposed to white light, while Plant B is exposed to green light of the same intensity. Which plant would likely show a higher rate of photosynthesis and why?
→ 11What is the function of the glomerulus in the nephron?
→ 12How do terrestrial plants exchange gases for respiration?
→ 13Describe the role of hydrochloric acid in the human stomach.
→ 14A doctor advises a patient to reduce their salt intake due to high blood pressure. How does high salt intake contribute to high blood pressure?
→ 15Which of the following scenarios would lead to the fastest rate of transpiration in a plant?
→ 16Why is the total energy yield of aerobic respiration much higher than that of anaerobic respiration?
→ 17In a biology experiment, a student places a plant under a bell jar with soda lime. Soda lime absorbs carbon dioxide. What would be the immediate effect on the plant's photosynthetic rate?
→ 18Why is it important for the human body to maintain a relatively constant internal temperature (homeostasis)?
→ 19What is the primary function of the renal artery and renal vein in relation to the kidney?
→ 20Explain the process of "guttation" in plants and why it occurs.
→ 21Assertion (A): Blood in arteries is always oxygenated. Reason (R): Arteries carry blood away from the heart to different organs.
→ 22If the transpiration rate in a plant is very high, how would this affect the concentration of minerals in the xylem sap?
→ 23Why is it advantageous for an amoeba to have a pseudopodia-based mode of nutrition?
→ 24What is the significance of the diaphragm in human respiration?
→ 25Which of the following is a direct product of the light-dependent reactions of photosynthesis?
→ 26Describe the role of valves in the human heart.
→ 27What would be the effect on digestion if the pancreas failed to secrete its digestive enzymes?
→ 28Why are carbohydrates stored as starch in plants and as glycogen in animals?
→ 29Which of the following is the correct sequence of parts through which urine passes in the human excretory system?
→ 30If a plant's roots are deprived of oxygen, how would this immediately affect its ability to absorb water and minerals?
→ 31A patient is diagnosed with kidney failure and undergoes dialysis. Explain the principle behind artificial kidney (dialysis) treatment.
→ 32Assertion (A): Veins have valves while arteries do not. Reason (R): Valves in veins prevent the backflow of blood, especially against gravity, as blood pressure is low in veins.
→ 33Which part of the digestive system absorbs the maximum amount of water from undigested food?
→ 34Describe the role of gastric glands in the human digestive system.
→ 35A person experiences symptoms like yellowish skin and eyes, and dark urine. Which organ is most likely malfunctioning?
→ 36Which of the following processes in plants requires energy (ATP) for the movement of substances?
→ 37Why is the left ventricle of the human heart thicker and more muscular than the right ventricle?
→ 38What happens to excess amino acids in the human body?
→ 39Explain how the large surface area for gas exchange is achieved in human lungs.
→ 40Why do aquatic organisms breathe much faster than terrestrial organisms?
→ 41A student observes that a healthy potted plant, when watered appropriately, still shows wilting during the hottest part of a summer day. Which process is most likely occurring at a higher rate than water absorption?
→ 42Which of the following is a primary function of xylem tissue in plants?
→ 43What would happen if the epiglottis failed to function properly during swallowing?
→ 44Why is it essential for plants to have stomata?
→ 45Assertion (A): Anaerobic respiration releases less energy than aerobic respiration. Reason (R): In anaerobic respiration, glucose is not completely broken down in the absence of oxygen.
→ 46Which of the following is an adaptation of the small intestine for efficient absorption of digested food?
→ 47A student observes a plant kept in a sealed transparent container. After some time, droplets of water appear on the inner surface of the container. What biological process is demonstrated here?
→ 48What would be the likely consequence if a person's lymphatic system were severely impaired?
→ 49Name the substance that prevents blood clotting inside the human body.
→ 50If the Bowman's capsule and glomerulus are collectively referred to as the renal corpuscle, which part of the nephron is primarily responsible for selective reabsorption of useful substances like glucose and amino acids?
→ 51Why do walls of the trachea have C-shaped cartilaginous rings?
→ 52In an experiment, if a plant is defoliated (leaves removed), how would this immediately affect the rate of water absorption by its roots?
→ 53Which of the following statements correctly describes the role of bile in the digestion of food?
→ 54During vigorous exercise, muscles may respire anaerobically. What is the end product of anaerobic respiration in human muscles, and what is its consequence?
→ 55A person suffers from a condition where their blood is unable to clot effectively after an injury. Which component of the blood is most likely deficient or malfunctioning?
→ 56Assertion (A): Human beings have a double circulatory system. Reason (R): In a double circulatory system, blood goes through the heart twice during each cycle, once for pulmonary circulation and once for systemic circulation.
→ 57Why is the inner lining of the small intestine folded into numerous finger-like projections called villi?
→ 58A student performs an experiment to study photosynthesis. They keep a potted plant with variegated leaves (some parts green, some non-green) in a dark room for 48 hours and then expose it to sunlight for 6 hours. After performing the iodine test, which part of the leaf would show the presence of starch and why?
→ 59Which of the following processes in plants involves the movement of water and dissolved minerals from the roots to the leaves against gravity?
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