Homeostasis Chapter 15 class 12 biology Sindh board New book

 

Q 01: Why is the physiological integration of internal body environment important for living organisms?

Ans: The physiological integration of the internal body environment is important for living organisms because it helps maintain optimal conditions for biochemical reactions necessary for life. This ensures that processes like enzyme activity, metabolic reactions, and cellular functions can occur within a narrow range of temperature, pH, and ion concentrations, allowing organisms to function properly.

Q 02: Why is it important that positive and negative feedback mechanisms counter act upon each other?

Ans: Positive and negative feedback mechanisms are important because they help maintain homeostasis, ensuring that physiological processes remain within a stable range. Positive feedback amplifies a response (e.g., blood clotting), while negative feedback counteracts it (e.g., regulating body temperature). The interaction of both mechanisms prevents extreme deviations and keeps the internal environment stable.

Q 03: How the aquatic Osmoregulators overcome the osmoregulatory problems?

Ans: Aquatic osmoregulators overcome osmoregulatory problems by regulating the concentration of salts and water in their bodies.

freshwater aquatic Osmoregulators tend to loss water by dilute urine and gain salts through gills

while Marine aquatic Osmoregulators continuously drink water and they remove a lot of salt in the form of concentrated urine.

Q 04: Why do animals excrete different types of excretory waste?

Ans: Animals excrete different types of excretory waste based on their physiology and habitat. For example, terrestrial animals often excrete urea, and some excrete uric acid while aquatic animals excrete ammonia. These variations optimize waste removal while conserving water and energy according to an organism's environment.

Q 05: What is the use of counter current mechanism in kidney?

Ans: The counter-current mechanism in the kidney is essential for concentrating urine and conserving water. It involves the flow of filtrate and blood in opposite directions in the nephron, creating a concentration gradient that allows for efficient reabsorption of water and solutes, aiding in urine concentration.

Q 06:What is the role of the kidney as an endocrine organ?

Ans: The kidney acts as an endocrine organ by producing hormones such as erythropoietin, which stimulates red blood cell production, and renin, which regulates blood pressure. These hormones help maintain homeostasis within the body.

Q 07: How are kidney stones formed?

Ans: Kidney stones form when minerals and salts (specially calcium oxalate) in urine crystallize and clump together and form hard mass which prevent urine flow. Factors like dehydration, diet, and genetics can contribute to their formation.

Q 08: What is the impact on the human body if kidneys suddenly or gradually lose their filtering abilities

Ans: If the kidneys suddenly or gradually lose their filtering abilities, the body accumulates waste products and excess fluids, leading to conditions like kidney failure. This can result in electrolyte imbalances, high blood pressure, anemia, and other health problems.

Q 09: What are the problems associated with kidney transplant?

Ans: Problems associated with kidney transplants can include rejection by the recipient's immune system, complications from surgery, the need for immunosuppressive drugs, and the scarcity of suitable donor organs.

Q 10: What is hypothermia? How body overcome this condition?

Ans: Hypothermia is a condition characterized by abnormally low body temperature. The body combats hypothermia by shivering to generate heat, constricting blood vessels to reduce heat loss, and seeking warmth. In severe cases, medical intervention like rewarming is necessary to raise the body temperature to a safe level.