01:119:116 Lecture Notes - Lecture 24: Body Cavity, Heart Sounds, Fluid Balance

• School: Rutgers University
• Department: Biological Science
• Course: 01:119:116
• Professor: Bendaoud

Document Summary

All animals need to exchange substances with their environment= nutrients, 02, and wastes (ex. C02) ultimately occurs by diffusion into and out of cells. Problem= diffusion is very slow over long distances. Some animals do not have a circulatory system don"t need it: flatworm flat body efficient diffusion, cnidarians gastrovascular cavity brings nutrients close to cells, nematodes fluid in pseudocoelom helps circulate materials. Animals with many layers of cells (especially if terrestrial) need a circulatory system: circulatory systems (cs) Circulatory system has 3 basic components: a circulatory fluid, a set of interconnecting vessels, a muscular pump= heart. Cs connects interstitial fluid with the organs that: Higher blood p= more efficient important in larger and more active animals. Ex. annelids, cephalopods, vertebrates: organization of vertebrate circulatory systems. Humans and other vertebrates have a closed circulatory system called the cardiovascular system. Composed of: blood will discuss in next lecture, heart two or more muscular chambers.