Explanation

• Diabetes mellitus causes polyuria because glucose increases osmotic pressure in renal tubules, pulling more water into urine.
• High blood sugar exceeds the renal threshold (~180 mg/dL), so glucose appears in urine (glycosuria).
• This extra glucose draws water with it, increasing urine volume (osmotic diuresis).
• Normal blood glucose is about 90–100 mg/dL (fasting).

Last verified on 14-06-2026

Explanation

• Heart rate increases during exercise due to increased sympathetic nervous system activity releasing norepinephrine.
• This prepares the body for higher oxygen and energy demand.
• It increases heart pumping strength and speed.
• More blood reaches muscles for ATP production.
• This is a normal physiological response during physical activity.

Last verified on 14-06-2026

Explanation

• The smooth endoplasmic reticulum (SER) is responsible for drug detoxification in liver cells.
• It contains enzymes that break down harmful drugs and toxins.
• This process makes substances less toxic and easier to excrete.
• Liver cells have abundant SER for this function.

Last verified on 14-06-2026

Explanation

• Alcohol acts as a depressant because it enhances GABA activity in the brain, which slows nerve signals.
• GABA is an inhibitory neurotransmitter that reduces brain activity.
• This leads to relaxation, slower reactions, and reduced coordination.
• Alcohol also suppresses excitatory signals.
• That is why it causes drowsiness and impaired judgment.

Last verified on 14-06-2026

Explanation

• The stomach secretes hydrochloric acid (HCl) to activate pepsinogen into pepsin for protein digestion.
• HCl creates an acidic environment in the stomach.
• This acidity helps enzymes work properly.
• It also kills harmful microbes in food.
• Thus, it supports digestion and protection.

Last verified on 14-06-2026

Explanation

• Drinking too much water quickly causes harm because it dilutes sodium levels in the blood (hyponatremia).
• Low sodium disrupts normal nerve and muscle function.
• Cells may swell due to water imbalance.
• This can affect brain function and become dangerous.

Last verified on 14-06-2026

Explanation

• Lactic acid builds up in muscles because oxygen supply becomes insufficient during intense exercise.
• Muscles switch to anaerobic respiration for quick energy.
• This produces lactic acid as a by-product.
• Accumulation causes muscle fatigue and burning sensation.
• It is a temporary process until oxygen levels recover.

Last verified on 14-06-2026

Explanation

• Cold water quenches thirst better because it reduces mouth temperature and stimulates nerve endings, giving a stronger refreshing feeling.
• This signals the brain that hydration is occurring.
• The cooling effect provides immediate relief from dryness.
• Warm water does not create this strong sensory response.
• That is why cold water feels more satisfying when thirsty.

Last verified on 14-06-2026

Explanation

• The liver is the most reliable organ for detecting chronic poisoning in forensic toxicology.
• It stores and metabolizes many toxins over time, showing long-term exposure.
• Chronic poisons like heavy metals accumulate in liver tissues.
• It is commonly examined in post-mortem toxicology tests.

Last verified on 14-06-2026

Explanation

• Vitamins are micronutrients required by the body in small amounts.
• They help in growth, immunity, metabolism, and overall health.

Additional information:

Micronutrients: Vitamins and minerals

Macronutrients: Carbohydrates, proteins, and fats

• Vitamin A → Vision
• Vitamin C → Immunity and wound healing
• Vitamin D → Healthy bones
• Vitamin K → Blood clotting

Last verified on 11-06-2026