Fiziologija ronjenja morskih sisavaca

undergraduate thesis

• Title (english): Diving physiology of marine mammals
• Author: Kristina Hrelja
• Mentor: Zoran Tadić (mentor)
• Granter: University of Zagreb; Faculty of Science; (Department of Biology); Zagreb
• Defense date and country: 2019-07-05, Croatia
• Scientific / art field, discipline and subdiscipline: NATURAL SCIENCES; Biology

Abstract

Morski sisavci uključuju tri reda: Carnivora (tu spada podred Pinnipedia), Cetacea i Sirenia. Oni imaju jednake karakteristike kao i svi ostali sisavci, ali za razliku od njih imaju brojne prilagodbe koje im omogućuju da provedu duge periode ispod površine vode. Kod nekih vrsta zabilježeni su zaroni u trajanju od čak dva sata. Tijekom rutinskih zarona u tijelu životinje odvija se aerobni metabolizam te se održava homeostazu u organizmu. To je vrlo važno, budući da neke vrste provedu cijeli život u moru izlazeći na površinu samo kako bi udahnuli zrak i napunili zalihe kisika u tijelu. Naime, oni mogu skladištiti veliku količinu kisika u tijelu, a glavna spremišta su im pluća, krv i mišići. Jedinstvene fiziološke prilagodbe tijekom zarona omogućuju im da optimalno iskoriste kisik koji im je na raspolaganju. Ubrzo nakon što zarone značajno im se uspore otkucaji srca, smanji se propusnost krvnih žila na periferiji, te dolazi do lokalne hipotermije. Razina metabolizma tijekom zarona je gotovo jednaka kao tijekom mirovanja. Tome, osim fizioloških promjena, značajno doprinosi određen način kretanja uz minimalni utrošak energije. Nadalje mišići su građom prilagođeni prvenstveno na aerobni metabolizam, no imaju i veliki aerobni kapacitet. Također, sposobni su tolerirati anoksične uvijete koji se stvaraju u organizmu kod duljih zarona.

Abstract (english)

Marine mammals include three orders: Carnivora (with the suborder Pinnipedia), Cetacea and Sirenia. They have the same characteristics as all other mammals, but they have many adaptations that allow them to prolong their diving period. Some species can even stay submerged for about 2 hours. Both homeostasis and aerobic metabolism are maintained during routine dives, which is very important, having in mind that some species spend their whole life in the ocean. All marine mammals breath with their lungs hence must occasionally come to the surface to breathe. In contrast to land mammals, they can store huge amounts of oxygen in their lungs, blood, and muscles. In addition, these animals exhibit profound physiological changes during diving. Their heartbeat slows down significantly and peripheral tissue perfusion decreases which leads to local hypothermia. Metabolism rate during a dive is almost the same as during rest. This is accomplished by using low-cost movement patterns together with previously mentioned physiological changes. Furthermore, their muscles are adapted to aerobic activity but also have a great anaerobic capacity. They also have various mechanisms for tolerating hypoxic conditions in their tissues.

• Keywords: morski sisavci
• Language: croatian
• URN:NBN: urn:nbn:hr:217:653013
• Study programme: Title: Ecology; Study programme type: university; Study level: undergraduate; Academic / professional title: sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) biologije (sveučilišni/a prvostupnik/prvostupnica (baccalaureus/baccalaurea) biologije)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2019-12-02 13:48:32