EXCRETORY PRODUCTS AND THEIR ELIMINATION
1. Categorize the following animals based on the nature of excretion of nitrogenous waste.
Mammals, Bony fishes, Birds, Aquatic amphibians, Insects, Cartilage fishes, Aquatic insects
2. In an informal discussion in your class, your friend made a comment that “Malpighian tubules are the kidneys of a cockroach.” How will you evaluate this statement?
1. Analyse the graph
a. What is the relationship between the amount of vasopressin in blood plasma and the blood volume? (1)
b. Suggest a situation in which the vasopressin decreases in the blood. (1)
1. Observe the figure. No need to redraw the figure. Label A and B and write the function of A and B.
1. a) Prepare a flowchart of filtrate flow in the nephron using the flow terms. (1)
Collecting duct, PCT, DCT, Ascending limb of Henle’s loop, descending limb of Henle’s loop, Bowman’s capsule
b) Counter current system plays an important role in concentrating urine. Name any two regions inside the kidney, where the counter current system is seen. (1)
1. Complete each of the following sentences using appropriate words. (4 x ½=2)
a. Ascending limb of Henle’s loop is ………… to water whereas the descending limb is …………… to water.
b. An excessive loss of fluid from the body stimulates the hypothalamus to release ………. hormone from ………
1. Identify the odd one and write the common features of the other items.
Nephridia, Malpighian tubules, Spicules, Kidney, Flame cells (1)
2. How the counter current mechanism helps to maintain the concentration gradient in the medullary interstitium? (2)
3. On a hot day would you expect your level of ADH in blood to be high or low? Explain. (2 score)