Question

6. Lungless salamanders live in moist habitats and can die if their skin dries out. Yet, some species cannotlive in water as adults and will drown if fully immersed. Why might this occur (consider the functional disadvantage of lungs in underwater) ? Why must their skin remain moist?

7. Define death in physiological terms. We know that when the human heart stops beating, it can be started again artificially. And, the subject lives. If the heart does not restart, the O2 supply is cut off, the brain "dies," but what does lack of O2 cause? Take your answer as far down (reductionistically) as you can.

8. You have designed a new drug (Provasoshut®) that acts as an agonist of alpha-adrenergic receptors. In most of the systems you have studied (e.g. capillary beds of the digestive system, liver, and adipose), Provasoshut® causes vasoconstriction that lasts for at least 15 minutes. However, when you tried the drug on the capillary beds of the contracting muscle of the frog leg prep in your physiology lab, the vasoconstriction lasted only 20 seconds! What is the best explanation for the short-lived action of Provasoshut® in this preparation?

9. A vampire bat survives on mammalian blood. Most cells in blood are erythrocytes filled mostly with water and hemoglobin. Most of plasma is water and its most abundant solute is albumin. Predict how the urine of a vampire bat would differ compared to an omnivorous mammal such as you.

Answer 1

6. Lungless Salamander, kind of species largely dependent on cutaneous respiration (gas exchange through moistened skin). Since they lack lungs, these organism breathe through their skin and the mucous membrane in the mouth and throat, these surfaces must remain moist at all times in order to absorb oxygen.They possess a pair of nasolabial grooves, and each groove extends from the upper lip to a nostril. The salamander touches its snout to a surface (nose tapping), and capillary action moves odour particles up the groove into the sensory cells in the vomeronasal organ of the nose.

Somes species cannot live in water as adults and will drown if fully immersed.This is true for many species, but there are a lot of amphibians that do not follow this life strategy. Salamanders may not have an aquatic larval stage. Most of amphibians are fully aquatic and they do not go through metamorphosis into adults. As the species of salamander lacks lungs, so they breathes by absorbing oxygen through its skin and the roof of its mouth. There skin remains moist inorder to absorb oxygen for their respiration.

7. In physological terms death is the irreversible cessation of all vital functions especially as indicated by permanent stoppage of the heart, respiration, and brain activity and the end of life. Ischemia is a condition commonly known as when "cramping of the heart muscle." Ischemia occurs when the narrowed coronary artery reaches a point where they fails to supply oxygen-rich blood to meet the heart's needs. As heart muscle becomes "starved" if fails to get enough oxygen for heart's needs.

8. New Drug Provsoshut is alpha adrenergic agonist. It's action on blood vessels there are two type of receptors Alpha 1 receptor and Beta 2 receptor. Adrenergic drugs that bind directly to one or more of these receptors to induce various physiologic effects. Drugs that mimic or interfere with the functioning of the sympathetic nervous system by affecting the release or action of norepinephrine and epinephrine. Adrenergic drugs that produce or inhibit these effects are known as sympathomimetic agents and sympatholytic agents

9. The urinary system of the vampire bat then uses various hormones to make concentrated urine consisting of more urea and less water, as we compared to vampire bat urine is more concentrated than ominivorous mammal.